Glossary of Terms and Acronyms

The total amount (mass) of water vapor per unit volume of air. Measured in units of gram per kilogram (g/kg).

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A measure of the amount of solar energy absorbed by a given substance of definite dimensions; the ratio of the amount of radiant energy absorbed to the total amount incident upon that substance.

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Device measuring changes in velocity in x,y, and z directions with respect to the aircraft.

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Altus Cumulus Electrification Study (ACES) was based at the Naval Air Facility Key West in Florida. ACES researchers in August 2002 tracked thunderstorms using an unmanned aerial vehicle (UAV) - allowing them to achieve dual goals of saftly gathering weather data and testing new aircraft technology. This marked the first time a UAV was used to conduct lightning research. The goal of the ACES project was to better understand the causes of an electrical storm.s fury and its effects on our home planet. Collaborators on ACES were: NASA Marshall Space Flight Center, Huntsville, AL; University of Alabama in Huntsville, Huntsville, AL; NASA Goddard Space Flight Center, Green Belt, MD; Pennsylvania State University, University Park, PA; General Atomics Aeronautical Systems, Inc., San Diego, CA.

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ADMIRARI (ADvanced MIcrowave RAdiometer for Rain Identification) is a unique passive microwave radiometer. It was built by Radiometer Physics, Meckenheim and delivered to the Meteorological Institute at the University of Bonn in summer 2007. It is designed to measure water vapor, cloud and rain liquid water with high temporal (1s) and spatial resolution (5deg). The radiometer is mounted on a trailer allowing relatively easy transportation and participation in field campaigns. Additionally it is equipped with two active instruments, i.e. since 2008 a Micro Rain Radar (MRR) at 24.1 GHz frequency for rain structure observation and since September 2010 with a Cloud Lidar at 920 nm wavelength for Cloud base estimation. (http://www2.meteo.uni-bonn.de/admirari)

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AMSU-B is a 5 channel microwave radiometer (89.0, 150.0, and 3 at 183.31Ghz) whose purpose is to receive and measure radiation from a number of different layers of the atmosphere in order to obtain humidity profiles.

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Atmospheric Emitted Radinace Interferometer, a passive Michelson interferometer observing in the near infrared portions of the spectrum, is used to remotely retrieve temperature and water vapor measurements.

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Electromagnetic radiation from small atmospheric constitiuents which is retro-reflected or emitted back to the source measuring device.

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The vertical profile produced based on the backscatter of certain wavelengths that are highly attenuated by aerosols and clouds.

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Forward scatter sensors collect light scattered in a forward direction. A typical sensor projects light outward that collides with particles in the air (fog, snow, dust, etc). These particles scatter light in all directions (primarily forward), and this sensor utilizes the stronger energy scattered forward toward a receiver that collects the light.

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The degree to which aerosols prevent light from passing through. Optical depth/thickness depends upon the physical constitution, the form and the concentration of particles.

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Adjectives describing the characteristics of Aerosol Particles, e.g. composition, size, diameter.

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The size of particles of solids or liquids that are suspended in air as an aerosol.

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The APS provides high-resolution, real-time aerodynamic measurements of particles from 0.5 to 20 micrometers, providing number-weighted, particle size distributions.

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An Aerosol is a colloidal system of liquid or solid particles dispersed in a gas.

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The Aerosonde is an unmanned aerial vehicle with a wingspan of a 2.9 meters (~9 feet) weighing approximately 14 Kg (~31 lbs). It carries a payload of air pressure, temperature and humidity probes.

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The aethaelometer is an instrument that measures suspended carbonaceous particulates, an important species of air pollutant.

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The Air Motion Sensor is a system comprised of the Pitot-Static System and Total Temperature Probe which determines the motion of the air with respect to the aircraft.

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Devices that measure air pressure

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A measure of the average kinetic energy of air molecules.

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Any weight-bearing vehicle designed for navigation in and through the air, supported by the action of air upon its surfaces or by the vehicle's own buoyancy

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An aircraft motion sensor is comprised of the GPS and INS plus associated hardware. Used to determine the motion of the aircraft with respect to the surface of the earth.

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Airspeed is the velocity of a vehicle through the atmosphere. Groundspeed is the velocity of a vehicle measured with respect to the ground.

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ALTUS is an Unmanned Aerial Vehicle (UAV) that is used to carry instruments for remote and direct sensing of atmospheric phenomena.

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A system used to collect data and events, such as flight and vehicle parameters from the Altus Unmanned Aerial Vehicle (UAV).

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The temperature of the surrounding environment.

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The Advanced Microwave Precipitation Radiometer is a passive microwave radiometer system on an airborne platform that collects data at 10.7 GHz, 19.35 GHz, 37.1 GHz, and 85.5 GHz.

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The Advanced Microwave Scanning Radiometer for EOS (AMSR-E) is a conically scanning total power passive microwave radiometer sensing microwave radiation (brightness temperatures) at 12 channels and 6 frequencies ranging from 6.9 to 89.0 GHz. Horizontally and vertically polarized radiation are measured separately at each frequency. The AMSR-E instrument was modified from the design used for the Advanced Earth Observing Satellite 2 (ADEOS-II) Advanced Microwave Scanning Radiometer (AMSR).

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The Advanced Microwave Scanning Radiometer for EOS Science Investigator-led Processing System (AMSRE-SIPS) at the GHRC DAAC has generated climate research quality data products since the launch of Aqua in the spring of 2002. With the implementation of NASA's Land Atmosphere Near real-time Capability for EOS (LANCE) in the summer of 2010 at the processing facility in Huntsville, the LANCE AMSR-E near-real-time products, with noted limitations, are generated and available to registered users via standard FTP with an average latency of less than 3 hours. While not a substitute for climate research quality products, near real-time products are in high demand in fields such as numerical weather prediction and forecasting, monitoring of natural hazards, disaster relief, agriculture and homeland security.

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The Advanced Microwave Scanning Radiometer 2 (AMSR2) onboard the Global Change Observation Mission – Water Satellite 1 (GCOM-W1) satellite is a remote sensing instrument for measuring weak microwave emission from the surface and the atmosphere of the Earth. From about 700 km above the Earth, AMSR2 will provide us highly accurate measurements of the intensity of microwave emission and scattering. The antenna of AMSR2 rotates once per 1.5 seconds and obtains data over a 1450 km swath. This conical scan mechanism enables AMSR2 to acquire a set of daytime and nighttime data with more than 99percent coverage of the Earth every 2 days.

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The Advanced Microwave Sounding Unit (AMSU) consists of a suite of 20 passive microwave radiometers. Two primary instruments, AMSU-A and AMSU-B, observe the earth in different parts of the microwave spectrum for different purposes.

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AMSU-A is a cross-track, line-scanned instrument designed to measure scene radiances in 15 discrete frequency channels which permit the calculation of the vertical temperature and moisture profile from about 3 millibars (~45 km) to the Earth's surface. Each scan has 30 cells, with a resolution of 3.3 degrees (50 km at nadir). The swath width is 2343 km (96.66 degrees). The AMSU-A instrument is made up of two separate modules, A1 and A2. AMSU-A1 contains the 13 highest frequencies (50.3 - 89 GHz) of various polarizations. AMSU-A2 contains the two lowest frequency channels (23.8 and 31.4 GHz), both vertically polarized.

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An instrument for measuring or indicating the force or speed of wind.

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The name of the exponent in the formula that describes the dependency of the aerosol optical thickness on wavelength; The exponent is indicative of coarse (such as dust) vs. fine mode aerosols.

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Absolute radiometric temperature incident upon the instrument antenna with no corrections for spurious energy received from sources not intended by the instrument design.

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The Second Generation Airborne Precipitation Radar (APR-2) system includes a real-time pulse compression processor, a fully-functional control and timing unit, and a very compact LO/IF module, all of which could be used in spaceborne applications. The cylindrical reflector antenna and linear feed array for the spaceborne PR-2 have been replaced by traveling wave tube amplifiers (TWTAs), front-end electronics, and an offset parabolic reflector antenna with mechanical scanning. The APR-2 looks downward and scans its beam across-track, with each scan beginning at 25 degrees to the left of nadir and ending at 25 degrees to the right. It uses the same scanning antenna reflector as that used for the Airborne Rain Mapping Radar (ARMAR), which consists of a 0.4 m offset reflector antenna with a mechanically scanned flat plate. The APR-2 antenna feed is a dual-frequency feed (13.4 and 35.6 GHz) and the aperture at 35.6 GHz is under-illuminated to provide matched beams at the two frequencies. This choice results in poor Doppler accuracy at Ka-band, but is needed for rain retrieval.

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The Autonomous Parsivel Unit (APU) is an optical disdrometer based on single particle extinction that measures particle size and fall velocity. This APU consists of the Parsivel, which was developed by OTT in Germany, and its support systems, which were designed and built by the University of Alabama in Huntsville.

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The Aqua satellite, launched 04 May 2002, is the continuing effort of NASA's Earth Science Enterprise (ESE) to observe and measure the state of the Earth system, while also monitoring global environmental changes over time. Aqua carries six state-of-the-art instruments in a near-polar low-Earth orbit. The six instruments are the Atmospheric Infrared Sounder (AIRS), the Advanced Microwave Sounding Unit (AMSU-A), the Humidity Sounder for Brazil (HSB), the Advanced Microwave Scanning Radiometer for EOS (AMSR-E), the Moderate-Resolution Imaging Spectroradiometer (MODIS), and Clouds and the Earth's Radiant Energy System (CERES). Each has unique characteristics and capabilities, and all six serve together to form a powerful package for making Earth observations. These data wil be processed into continuous long-term measures of the state of the atmosphere, land, and oceans.

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Pressure caused by the weight of the atmosphere. At sea level it has a mean value of one atmosphere but reduces with increasing altitude.

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The measure of the atmosphere to allow the passage of electical current. Above 100m, atmospheric conductivity decreases, thus increasing the electic field.

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A measure of the columnar liquid water, as in clouds or rain, in the atmosphere in units of milligrams per square centimeter.

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The pressure exerted by the weight of air above a given point. Usually expressed in terms of the height of a column of mercury.

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The pressure exerted by the weight of air above a given point. Usually expressed in terms of the height of a column of mercury.

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This relative aerosol measurement represents the total backscattering of aerosols and molecules divided by a molecular density profile, which was determined using a tropical molecular density profile derived from the Standard Atmosphere.

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Atmospheric temperature is a measure of temperature at different levels of the Earth's atmosphere. It is governed by many factors, including incoming solar radiation, humidity and altitude.

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Gaseous form of water found in the atmosphere.

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Rate of air motion

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The settings of the aircraft's instruments that maintains a specific mode of flight, the position of aircraft in relation to the horizon plane.

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The Airborne Vertical Atmosphere Profiling System (AVAPS) uses dropwindsondes incorporating Global Positioning System (GPS) receivers to measure the atmospheric state parameters during their descent. Dropwindsondes measure vertical profiles of pressure, temperature, and humidity. Three dimensional position information from the GPS yields the vertical wind structure.

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The Advanced Very High Resolution Radiometer (AVHRR) is a five-channel scanning instrument that quantitatively measures electromagnetic radiation, flown on NOAA environmental satellites. The AVHRR remotely determines cloud cover and surface temperature. Visible and infrared detectors observe vegetation, clouds, lakes, shorelines, snow, and ice.

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The AXIS P1343-E network camera has day/night functionality with an automatically controlled IR filter, adapting to both daylight and dark lighting conditions.

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The scattering of radiant energy by aerosols (solid particles or liquid droplets) into the hemisphere of space bounded by a plane normal to the direction of the incident radiation and lying on the same side as the incident ray.

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The measurements of energy that is reflected back to a detector.

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A non-permeable, inflatable membrane made of a light material, filled with a gas lighter than air, designed to rise or float in the atmosphere.

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An instrument used for determining atmospheric pressure. The two most common barometers are the mercury barometer and the aneroid barometer.

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The conversion of kinetic energy into heat by work done against the viscous stresses in the boundary layer.

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Effective temperature of a blackbody radiating the same amount of energy per unit area at the same wavelengths as the observed body; also called effective temperature.

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The Conically-Scanning Two-look Airborne Radiometer is a passive microwave radiometer system on an airborne platform that collects data at 37.1 GHz. Making use of a rotating antenna, the C-STAR is able to produce images forward and aft of the aircraft ground track. Data is collected in both horizontal and vertical polarization for each of the forward and aft images.

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The Canadian CloudSat/CALIPSO Validation Project (C3VP) is part of the international CloudSat program. With C3VP, the Meteorological Service of Canada (MSC), Environment Canada, has been performing extensive validation of the satellite products in the context of the Canadian climate.

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A Camera is an apparatus for taking photographs, generally consisting of a lightproof enclosure having an aperture with a shuttered lens through which the image of an object is focused and recorded on a photosensitive film or plate.

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The Convection and Moisture Experiments (CAMEX-1) were NASA funded experiments designed to study the three-dimensional moisture fields using satellite, aircraft, and ground-based instrumentation and the multifrequency radiometric and lightning signatures of tropical convection in support of the Mission to Planet Earth. The geographic domain of the CAMEX region was between 25 degrees North to 45 degrees North latitude and 70 degrees West to 83 degrees West longitude. 1993-09-08 through 1993-10-07.

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The second Convection and Moisture Experiments (CAMEX-2) were NASA funded experiments designed to study the three-dimensional moisture fields using satellite, aircraft, and ground-based instrumentation and the multifrequency radiometric and lightning signatures of tropical convection in support of the Mission to Planet Earth. The geographic domain of the CAMEX region was between 25 degrees North to 45 degrees North latitude and 70 degrees West to 83 degrees West longitude. 1995-08-23 through 1995-09-02.

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The Third Convection and Moisture Experiment (CAMEX-3). The Convection and Moisture Experiment (CAMEX) is a series of field research investigations sponsored by the Earth Science Enterprise of the National Aeronautics and Space Administration (NASA). The Third field campaign in the CAMEX series (CAMEX-3) was scheduled for 6 August through 23 September, 1998, to study tropical cyclone development, tracking, intensification, and landfalling impacts using NASA-funded aircraft and surface remote sensing instrumentation.

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The Convection And Moisture EXperiment (CAMEX) is a series of field research investigations sponsored by the Earth Science Enterprise of the National Aeronautics and Space Administration (NASA). The fourth field campaign in the CAMEX series (CAMEX-4) ran from 16 August to 24 September, 2001 and was based out of Jacksonville Naval Air Station, Florida. CAMEX-4 focused on the study of tropical cyclone (hurricane) development, tracking, intensification, and landfalling impacts using NASA-funded aircraft and surface remote sensing instrumentation.

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The Convection and Precipitation/Electrification Experiment (CaPE) took place in central Florida with a latitude range of 43N, to 25.5N, westernmost longitude of 86W, and easternmost longitude of 69W. The CaPE Flight Activity began on July 18, 1991 and ended on Aug. 17, 1991. Making use of the Advanced Microwave Precipitation Radiometer (AMPR) on board on a NASA ER-2 aircraft flying at a nominal 20km altitude, passive microwave measurements were made of convective activity. The purpose of the experiment was to collect precipitation data in tropical convective storm cells over both water and land. Data returned included ice/water concentrations and amounts, and the structure of the convective cells.

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The Clouds, Aerosol and Precipitation Spectrometer (CAPS) is a combination of two optical sensors, the Cloud Imaging Probe (CIP) and the Cloud and Aerosol Spectrometer (CAS). The CAS uses forward-scatter and back-scatter techniques to measure particles from 0.5 micrometers to 50 micrometers. The CIP uses a fast 64-element photodiode array to generate 2-Dimensional Images of particles from 25-1550 micrometers.

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A colorless odorless incombustible gas present in the atmosphere and formed during respiration, the decomposition and combustion of organic compounds.

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Carbon monoxide (CO) is a colorless, odorless and tasteless gas, yet very toxic to humans and animals. It consists of one carbon atom and one oxygen atom, connected by a covalent double bond and a dative covalent bond. It is the simplest oxocarbon, and is an anhydride of formic acid.

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The concentration of carbon monoxide (CO), a compound of carbon and oxygen containing one atom of oxygen in each molecule, colorless and odorless gas.

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Cloud Droplet Probe: This miniature, lightweight, low-power cloud particle spectrometer measures droplets in the range of 2-50 µm in concentrations as high as 2000 particles/cm3.

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An automatic, recording, cloud-height indicator.

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The Cloud Imaging Probe (CIP) is a particle spectrometer which measures the size and shape of cloud particles from 75 micrometers to 1550 micrometers, using a 64-element linear diode array at an image resolution of 25 micrometers per pixel. Particle size distributions, derived parameters, and particle images are available from this instrument. It is developed by Droplet Measurement Technologies, Inc.

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Marshall Space Flight Center internal inventory table used for cataloging metadata

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A collection of data from various sources measuring various parameters. Watershed data, for example, is comprised of rainfall information gathered from rain gauge networks and stream flow measurements which are used in conjunction with topographical information, vegetation and soil and ground permeability to determine the fate of water falling in a defined area. Data from these sources are collected over a period of years in order to better understand the long term patterns.

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A source of regularly occurring pulses used to measure the passage of time.

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The difference in scattering due to cloud hydrometeors between the forward and backward directions.

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For a given cloud or cloud layer, the lowest level in the atmosphere at which the air contains a perceptible quantity of cloud particles.

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For a given cloud or cloud layer, the temperature at the lowest level in the atmopshere at which the air contains a perceptible quantity of cloud particles.

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The altitude based on the cloud height

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Cloud particles as small as molecules and up in size through precipitation elements around which droplets condense in the atmosphere.

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The physical size of water droplets and the number of water droplets recorded in a given area or volume within a cloud.

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Count of cloud particles with specified diameter per unit volume per unit size range

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The physical size of water droplets and the number of water droplets recorded in a given area or volume within a cloud.

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(Total Cloud Cover) Fraction of the sky hidden by all visible clouds.

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The height of a cloud measured from its base to the top

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The Cloud Lidar is an instrument which combines a pulsed laser transmitter and optical receiver (usually a telescope) with an electronic signal processing unit used for the detection and ranging of various distant targets in the atmosphere, analogous to the principles of operation of microwave radar. The cloud lidar is an active instrument used for Cloud base estimation.

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A measure of the columnar liquid water, as in clouds or rain, in the atmosphere in units of milligrams per square centimeter.

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The amount of liquid water/ice crystals resident in clouds per unit volume of air.

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The cloud particle imager (CPI) is a probe that uses a three laser system for detection and imaging of particles passing through the system. It can image and count particles in the size range of 15-2500um.

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Condensed material in clouds with negligible small fall speeds

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The key characteristics of a cloud such as height, vertical growth, amount of water vapor.

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A measure of the columnar liquid water, as in clouds or rain, in the atmosphere in units of milligrams per square centimeter. Also includes rain indicator.

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A visible aggregate of minute water droplets and/or ice particles in the atmosphere above the earth's surface.

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CMORPH (CPC MORPHing technique) produces global precipitation analyses at very high spatial and temporal resolution. This technique uses precipitation estimates that have been derived from low orbiter satellite microwave observations exclusively, and whose features are transported via spatial propagation information that is obtained entirely from geostationary satellite IR data.  http://www.cpc.ncep.noaa.gov/products/janowiak/cmorph_description.html

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A measure of the columnar water vapor in the earth's atmosphere in grams per square centimeter.

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An electronic device designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations.

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A particle counter which measures the number concentration of individual particles that are a specific diameter. Size measured depends on the characteristics of the specific instrument.

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The Coriolis satellite is a Naval Research Laboratory and Air Force Research Laboratory earth and space observation satellite launched from Vandenberg Air Force Base, on 2003-01-06 at 14:19 GMT.

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A measure of the correlation of the horizontal and vertical back scattered power within a radar sample volume.

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Compact Scanning Millimeter-wave Imaging Radiometer (CoSMIR), originally developed for the calibration/validation of the Special Sensor Microwave Imager/Sounder (SSMIS), is an airborne, 9-channel total power radiometer modified to have scan mode to acquire both conical and across-track scan data simultaneously in a given flight. The well-calibrated radiometric data between 50-183 GHz has an accuracy on the order of ±1 K.

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A cloud particle counter is an instrument that detects and counts cloud particles.

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The Cloud Particle Imager (CPI) contains a particle detection system (PDS), and a laser imaging system and provides particle imagery over a range of sizes from 20 to 2000 microns with a 2-micron resolution. The CPI is especially suitable for use in ice and mixed phase clouds which typically have relatively low (compared to water clouds) particle concentration of 1000/L.

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NGDC's 3 arc-second U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone, integrating offshore bathymetry with land topography into a seamless representation of the coast. The CRM spans the U.S. East and West Coasts, the northern coast of the Gulf of Mexico, Puerto Rico, and Hawaii, reaching out to, and in places even beyond, the continental slope.

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CRS (Cloud Radar System) is a coherent Doppler radar system at 94 GHz. CRS provides vertically profiled reflectivity and Doppler velocity at aircraft nadir along the flight track.

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The NCAR Counterflow Virtual Impactor (CVI) is an airborne instrument used to measure cloud particle/droplets of a size greater than about 8 microns in diameter, and cloud condensation nuclei (CCN) by using a counter flow stream of dry nitrogen gas out of the tip of the probe. This flow is sufficiently strong to displace particles/droplets of smaller diameter. Once through the probe, water vapor and residual nonvolatile materials (CCN) are sampled and measured.

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The Dual-frequency Dual-polarized Doppler Radar (D3R) is a fully polarimetric, scanning weather radar system operating at the nominal frequencies of 13.91 GHz and 35.56 GHz covering a maximum range of 30 km.

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The mean of the data values over a 24 hour period

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The start, end and duration of a vehicle's departure from the ground.

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DAWN (Doppler Aerosol WiNd lidar), a pulsed laser, 2-micron, and solid-state lidar, can provide vertical profiles of u, v, and w components of 3-D wind in the region below the aircraft. It pulses at 10 Hertz with 250 mJ pulses that are 200 ns long full width at half maximum (FWHM). Using the wedge scanner, five different azimuth angles are measured: 1) to end up with five equations for the three unknown components of wind vs. altitude, 2) to mitigate cloud obscurations, and 3) to measure the atmospheric variability.

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The temperature to which a parcel of air must be cooled to produce condensation.

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The temperature to which a parcel of air must be cooled to produce condensation.

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The temperature to which a sample of air must be cooled, with air pressure constant, in order to attain saturation.

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An instrument for determining the specific gravity of liquids at their dew-point.

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Differential Absorption Lidar - uses the backscatter of four simultaneous laser wavelengths through zenith and nadir quartz windows to measure the vertical profiles of O3 and aerosols/clouds.

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The difference between propagation constants for horizontally- and vertically- polarized radar pulses.

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A measure of the reflectivity-weighted mean axis ratio of the hydrometeors in a radar volume.

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The Diode Laser Hygrometer (DLH), developed by NASA's Langley and Ames Research Centers, has flown on the NASA DC-8 during several field campaigns. The DLH is a near-infrared spectrometer operating near 1.4 microns, and was developed for in situ measurements of atmospheric water vapor (H 2O(v)) from aircraft platforms. It is based upon near-infrared tunable diode technology. This spectrometer provides true in situ monitoring of water vapor concentrations with precision levels exceeding those of existing Lyman alpha and frost point hygrometers.

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The primary objective of the Distributed Information Services for Climate and Ocean Products and Visualizations for Earth Research (DISCOVER) Project is to provide highly accurate, long-term ocean and climate products suitable for the most demanding Earth research applications via easy-to-use display and data access tools. These products are derived from a large network of satellite microwave sensors going back to 1979. Most of the products are produced in near real-time (3-12 hours) on a 24x7 basis and hence are also suitable for some weather applications. The products include sea-surface temperature and wind, air temperature, atmospheric water vapor, cloud water, and rain rate. A key element of DISCOVER is the merging of multiple sensors from multiple platforms into geophysical data sets consistent in both space and time. DISCOVER is a follow-on activity to the Passive Microwave - Earth Science Information Partner (PM-ESIP) and SSM/I-SSMIS (Special Sensor Microwave/Imager - Special Sensor Microwave Imager/Sounder) Pathfinder projects and builds on user interface technology available through these programs. In addition, DISCOVER contains a Technology Development component that provides an extended set of user services and visualization tools to greatly enhance the utility of the products and increase online analysis of these data.

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A disdrometer is an instrument used to measure the drop size distribution and velocity of falling hydrometeors.

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Defense Meteorological Satellite Program. A series of meteorological spacecraft controlled by the U.S. Air Force Space and Missiles System. The DMSP program designed, built, launched, and maintained several near polar orbiting, sun synchronous satellites monitoring the meteorological, oceanographic, and solar-terrestrial physics environments. Now declassified, data from DMSP is maintained at the National Oceanic and Atmospheric Administration (NOAA)'s National Centers for Environmental Information (NCEI).

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Controlled by the Defense Meteorological Satellite Program, DMSP F1 was the first satellite launched of the Block 5D series. It was launched Sept. 11, 1976 and mission ended Sept. 17,1979. It was a noon-midnight sun-synchronous orbit with the altitude between 798 and 853 km, inclination of 99.0 degrees, and period of 101.4 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F3 was the third satellite of the Block 5D series of DMSP satellites, launched April 30, 1978. It was in a noon-midnight sun-synchronous orbit with the altitude between 797 and 855 km, inclination of 98.8 degrees, and period of 101.5 minutes. Its mission ended in December of 1979.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F10 was the tenth block 5D satellite launched on December 1, 1990. The mission ended February 1995 when the bearings on the momentum flywheels seized and caused the spacecraft to tumble. F10 had an approximate crossing time of 10:09 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F11 was the 11th block 5D satellite,launched on November 28, 1991. The mission ended August 2000. F-11 had an approximate equator crossing time of 6:30 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F12 was twelvth in the block 5D satellite launched on Auguest 29, 1994. This sun-synchronous satellite has an equator crossing time of 9:30 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F13 is the thirteenth block 5D satellite launched on March 24, 1995. F13 has an approximate equator crossing time of 5:45 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F14 is the fourteenth of the block 5D satellites, launched on April 4, 1997. F14 has an approximate equator crossing time of 5:05 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F15 is the fifteenth of the block 5D satellites, launched on April 27, 2000. F15 has an approximate equator crossing time of 9:20 AM/PM and is still operational.

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A spacecraft controlled by the Defense Meteorological Satellite Program which originated as a long-term U.S. Air Force effort but are now declassified. DMSP-F17 was the seventh launched of the Block 5D series. It was launched Nov. 18, 1983 and the mission ended October 17, 1987. It was a noon-midnight sun-synchronous orbit with the altitude between 815 and 832 km, inclination of 98.7 degrees, and period of 101.5 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F8 is the eighth of the block 5D satellites, launched on June 18, 1987. The mission ended August 13, 1991. F8 had an approximate equator crossing time of 6:17 AM/PM.

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A spacecraft controlled by the Defense Meteorological Satellite Program which originated as a long-term U.S. Air Force effort but is now declassified. DMSP F9 was the ninth launched of the Block 5D series. It was launched Feb. 3, 1988 and the mission ended March 1992. It was a noon-midnight sun-synchronous orbit with the altitude between 815 and 826 km, inclination of 98.7 degrees, and period of 101.4 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F15 is the fifteenth of the block 5D satellites, launched on April 27, 2000. F15 has an approximate equator crossing time of 9:20 AM/PM and is still operational.

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Defense Meteorological Satellite Program (DMSP-F16) is a U.S. Department of Defense weather satellite launched by a Titan 2 rocket from Vandenberg AFB at 16:17 UT on 18 October 2003. DMSP-F16 carried two new experiments: the limb scanning ultraviolet imager/spectrometer SSULI (Special Sensor Ultraviolet Limb Imager) built by the Naval Research Laboratory and the nadir scanning ultraviolet imager/spectrometer and photometer SSUSI (Special Sensor Ultraviolet Spectrographic Imager) built by the Applied Physics Laboratory at Johns Hopkins University. It also carried new versions of the Special Sensor for Ions, Electrons and Scintillations (SSIES-13) and of the precipitating ion and electron monitor Special Sensor J/5 (SSJ/5). F16 has an approximate crossing time of 8 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F17 block 5D-3 is a U.S. Department of Defense weather satellite launched by a Delta 4 rocket from Vandenberg AFB at 13:53 UT on 04 November 2006. It carries a payload similar to those on DMSP F16 and F15, to provide infrared and visible light images, and some data of ionospheric and magnetospheric import. F17 has an approximate crossing time of 5:30 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F18 block 5D-3 is a U.S. Department of Defense weather satellite launched on an Atlas 5 rocket on October 18, 2009 at 16:12 UT from Vandenberg. The 1,200 kg satellite provides terrestrial space weather data from a near-polar, sun-synchronous, 830 km altitude orbit. The primary weather sensor on DMSP is the Operational Linescan System (OLS), which provides continuous visual and infrared imagery of cloud cover. Additional satellite sensors measure atmospheric vertical profiles of moisture and temperature. DMSP satellites also measure space environmental parameters such local charged particles and electromagnetic fields. F18 has an approximate crossing time of 8 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F19 block 5D-3 is a U.S. Department of Defense weather satellite launched on an Atlas 5 rocket on April 3,2014 at 14:46 UT from Vandenberg. DMSP satellites see environmental features such as clouds, bodies of water, snow, fire, and pollution in the visual and infrared spectra. The data can be used to determine cloud type and height, land and surface water temperatures, water currents, ocean surface features, ice, and snow. DMSP data are processed on the ground, interpretedby meteorologists, and ultimately used in planning and conducting U.S. military operations worldwide. F19 has an approximate crossing time of 6:30 AM/PM and is still operational.

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A spacecraft controlled by the Defense Meteorological Satellite Program which originated as a long-term U.S. Air Force effort but is now declassified. DMSP 5B F3 was the third launched of the Block 5B series. It was launched Nov. 9, 1972. It was a sun-synchronous polar orbit with the altitude between 813 and 872 km, inclination of 98.7 degrees, and period of 101.8 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP F1 was the first satellite launched of the Block 5D series. It was launched Sept. 11, 1976 and mission ended Sept. 17,1979. It was a noon-midnight sun-synchronous orbit with the altitude between 798 and 853 km, inclination of 99.0 degrees, and period of 101.4 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F10 was the tenth block 5D satellite launched on December 1, 1990. The mission ended February 1995 when the bearings on the momentum flywheels seized and caused the spacecraft to tumble. F10 had an approximate crossing time of 10:09 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F11 was the 11th block 5D satellite,launched on November 28, 1991. The mission ended August 2000. F-11 had an approximate equator crossing time of 6:30 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F12 was twelvth in the block 5D satellite launched on Auguest 29, 1994. This sun-synchronous satellite has an equator crossing time of 9:30 AM/PM.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F13 is the thirteenth block 5D satellite launched on March 24, 1995. F13 has an approximate equator crossing time of 5:45 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F14 is the fourteenth of the block 5D satellites, launched on April 4, 1997. F14 has an approximate equator crossing time of 5:05 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F15 is the fifteenth of the block 5D satellites, launched on April 27, 2000. F15 has an approximate equator crossing time of 9:20 AM/PM and is still operational.

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Defense Meteorological Satellite Program (DMSP-F16) is a U.S. Department of Defense weather satellite launched by a Titan 2 rocket from Vandenberg AFB at 16:17 UT on 18 October 2003. DMSP-F16 carried two new experiments: the limb scanning ultraviolet imager/spectrometer SSULI (Special Sensor Ultraviolet Limb Imager) built by the Naval Research Laboratory and the nadir scanning ultraviolet imager/spectrometer and photometer SSUSI built by the Applied Physics Laboratory at Johns Hopkins University. It also carried new versions of the Special Sensor for Ions, Electrons and Scintillations (SSIES-13) and of the precipitating ion and electron monitor Special Sensor J/5 (SSJ/5). F16 has an approximate crossing time of 8 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F17 block 5D-3 is a U.S. Department of Defense weather satellite launched by a Delta 4 rocket from Vandenberg AFB at 13:53 UT on 04 November 2006. It carries a payload similar to those on DMSP F16 and F15, to provide infrared and visible light images, and some data of ionospheric and magnetospheric import. F17 has an approximate crossing time of 5:30 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F18 block 5D-3 is a U.S. Department of Defense weather satellite launched on an Atlas 5 rocket on October 18, 2009 at 16:12 UT from Vandenberg. The 1,200 kg satellite provides terrestrial space weather data from a near-polar, sun-synchronous, 830 km altitude orbit. The primary weather sensor on DMSP is the Operational Linescan System (OLS), which provides continuous visual and infrared imagery of cloud cover. Additional satellite sensors measure atmospheric vertical profiles of moisture and temperature. DMSP satellites also measure space environmental parameters such local charged particles and electromagnetic fields. F18 has an approximate crossing time of 8 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F19 block 5D-3 is a U.S. Department of Defense weather satellite launched on an Atlas 5 rocket on April 3,2014 at 14:46 UT from Vandenberg. DMSP satellites see environmental features such as clouds, bodies of water, snow, fire, and pollution in the visual and infrared spectra. The data can be used to determine cloud type and height, land and surface water temperatures, water currents, ocean surface features, ice, and snow. DMSP data are processed on the ground, interpretedby meteorologists, and ultimately used in planning and conducting U.S. military operations worldwide. F19 has an approximate crossing time of 6:30 AM/PM and is still operational.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F3 was the third satellite of the Block 5D series of DMSP satellites, launched April 30, 1978. It was in a noon-midnight sun-synchronous orbit with the altitude between 797 and 855 km, inclination of 98.8 degrees, and period of 101.5 minutes. Its mission ended in December of 1979.

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A spacecraft controlled by the Defense Meteorological Satellite Program which originated as a long-term U.S. Air Force effort but are now declassified. DMSP-F17 was the seventh launched of the Block 5D series. It was launched Nov. 18, 1983 and the mission ended October 17, 1987. It was a noon-midnight sun-synchronous orbit with the altitude between 815 and 832 km, inclination of 98.7 degrees, and period of 101.5 minutes.

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Controlled by the Defense Meteorological Satellite Program, DMSP-F8 is the eighth of the block 5D satellites, launched on June 18, 1987. The mission ended August 13, 1991. F8 had an approximate equator crossing time of 6:17 AM/PM.

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A spacecraft controlled by the Defense Meteorological Satellite Program which originated as a long-term U.S. Air Force effort but is now declassified. DMSP F9 was the ninth launched of the Block 5D series. It was launched Feb. 3, 1988 and the mission ended March 1992. It was a noon-midnight sun-synchronous orbit with the altitude between 815 and 826 km, inclination of 98.7 degrees, and period of 101.4 minutes.

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A Doppler radar has the capability of measuring some information about winds (on top of the usual echo strength all radars measure) by using the Doppler effect.

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Radial velocity (velocity toward or away from the radar site) of radar illuminated objects.

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The Dual Optical Pulse Sensor (DOPS) are two-time resolved optical pulse sensors viewing at two different frequencies with a very wide Field of View (FOV) of 50deg, an all sky detector, a video camera with VCR tape storage, and associated data acquisition systems for the optical pulse sensors.

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The physical size of water droplets and the number of water droplets recorded in a given area or volume within a cloud.

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The physical size of water droplets and the number of water droplets recorded in a given area or volume.    There is no defined size limit separating droplets from drops of water, but it is sometimes convenient to denote two disparate size ranges, such as the oft-used distinction of liquid cloud particles (droplets) from liquid precipitation (drops), thereby implying that a maximum diameter of 0.2 mm (0.008 in.) is the limit for droplets.

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Sometimes also referred to as "dropwindsondes". An instrument package which contains a temperature sensor (thermistor), a moisture sensor (hygrometer) and a GPS receiver which determines the position of the package in time and 3 dimensional space. Upon release, the dropwindsonde transmits data to the releasing aircraft (DC-8, WC-130, WP-3) where the data is collected and saved. When subsequently analysed, the resultant sounding yields temperature, dewpoint and windspeed observed by the instrument.

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Two time resolved optical pulse sensors viewing at two different frequencies with a very wide field of view (FOV) (50deg), an all sky detector, a video camera with VCR tape storage, and associated data acquisition systems for the optical pulse sensors.

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The European Centre for Medium-range Weather Forecasts (ECMWF) is an international agency supported by various European countries. The ECMWF began producing operational medium-range weather forecasts in 1979. The Centre objectives include the development of medium-range forecast models, the generation and distribution of that forecast information and research relating to improving forecasting techniques.

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European Center for Medium-range Weather Forecast Model: an operational analysis-forecasting system. One use of this model is for estimating global precipitation.

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The ER-2 Doppler radar (EDOP) is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The instrument has two fixed antennas, one pointing at nadir and the second pointing approximately 33 degree ahead of nadir.

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An abstract concept analogous to magnetic field. Useful in determining a force that a test charge (a point source of known electric charge) would experience in the vicinity of another point charge. A single positive (negative) point charge produces an electric field directed outward (inward). Measured in volts/meter.

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Electric field mills are used to measure the vertical component of the electric field as the aircraft flies in the vicinity of electrified clouds. The dynamic range of these instruments extends from the fair weather fields (a few tens of V/m) to large thunderstorm fields (thousands of V/m). Using these field mills, it is possible to detect both intracloud and cloud-to-ground lightning from the abrupt electric field changes in the data.

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The ratio of the radiation emitted by a surface to the radiation emitted by a perfect blackbody radiator at the same temperature.

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The Landsat Enhanced Thematic Mapper Plus (ETM+) is a sensor carried onboard the Landsat 7 satellite and has acquired images of the Earth nearly continuously since July 1999, with a 16-day repeat cycle. Landsat ETM+ image data consist of eight spectral bands with a spatial resolution of 30 meters for bands 1 to 5 and band 7. More information can be found at https://www.usgs.gov/centers/eros/science/usgs-eros-archive-landsat-archives-landsat-7-enhanced-thematic-mapper-plus-etm (Level-1) and https://www.usgs.gov/centers/eros/science/usgs-eros-archive-landsat-archives-landsat-7-etm-plus-collection-2-level-2 (Level-2).

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The Earth Network Lightning Sensors (ENLS) employs time-of-arrival detection methodology along with GPS technology and sophisticated algorithms on the entire waveform for every stroke to accurately locate and classify lightning types [IC (intra-cloud) / CG (cloud-to-ground)].

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The Earth Networks Total Lightning Network (ENTLN) is an integrated in-cloud (IC) lightning and cloud-to-ground (CG) detection network deployed on a global basis capable of detecting long range in-cloud lightning at high efficiencies critical for the advanced prediction of severe weather phenomena. More information is found at http://earthnetworks.com/Products/TotalLightningNetwork.

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This project addresses the question of how extensive land use change or more subtle regional climate variations modify the natural functioning and structure of the Amazonian ecosystems, from routing of water and its chemical load through precipitation and drainage systems back to the atmosphere and the oceans. The primary area of interest is 20S-6N, 45W-80W.

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The process by which soil, rock or sand is gradually worn away by water or wind action.

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The natural processes relating to the break down of soil and rock, and the movement and deposition of the resulting particles.

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An index of extreme sea surface temperature (SST) in the eastern tropical Pacific.

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Soil maps from the Food and Agriculture Organization (FAO) at 1:5M scale. Includes major and associated soil units for each land cell; surface texture, surface slope, phase, and miscellaneous land units where available.

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A "Slow" and "Fast" antennas system acquires lightning waveforms and provides a measure of total lightning. The system consists of a flat plate antenna anda broadband charge amplifier with a selectable time constant (i.e., "slow antenna" or "fast antenna"), a filter for removing undesired signals (e.g., radio frequency interference), a transient waveform recorder, and a data acquisition system.

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The FD12P Weather Sensor combines the function of a forward scatter visibility meter and a present weather detector. It additionally measures the intensity and amount of both liquid and solid precipitation. The FD12P is made by Vaisala.

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An instrument which detects and measures the electrostatic field strength within the instrument field of view using stainless steel plates (stators) which are alternatively shielded and exposed to the existing atmospheric electric field by a grounded rotor. By comparing the differences between the two measurements, a determination of the observed field strength is made.

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Field surveys are primary data observations and measurements that are taken from multiple locations along a transect.

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An instrument designed to measure absolute humidity of the atmosphere.

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FIRE, the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment, studied a variety of Arctic cloud systems under spring and summer conditions. A team of national and international scientists conducted the FIRE Arctic Cloud Experiment (ACE) in a two-phase field campaign-- the first phase of which began in April, 1998, with a second phase conducted during July, 1998. The scientific objectives of FIRE ACE were to study impact of Arctic clouds on radiation exchange between surface, atmosphere, and space, and the influence of surface characteristics of sea ice, leads, and ice melt ponds on these clouds. FIRE ACE attempted to document, understand, and predict the Arctic cloud-radiation feedbacks, including changes in cloud fraction and vertical distribution, water vapor cloud content, cloud particle concentration and size, and cloud phase as atmospheric temperature and chemical composition change. FIRE ACE data is used to focus on improving current climate model simulations of the Arctic climate, especially with respect to clouds and their effects on the surface energy budget. In addition, FIRE ACE investigated a number of scientific questions dealing with radiation, cloud microphysics, and atmospheric chemistry.

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A fixed, somewhat permanent point from which measurements or surveys are made.

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A record of instrument, flight and vehicle status.

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Wind speed and direction observed by an aircraft at a specific location and time.

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The trajectory of a moving aircraft or spacecraft relative to a fixed reference.

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Fluxgate Magnetometer: an instrument that measures the orientation and strength of magnetic lines of flux. Fluxgate magnetometers are used to anaylze the Earth'magentic field intensity and changes.

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The Forward Scattering Spectrometer Probe, Model 300 (FSSP-300) Aerosol Spectrometer sizes particles by measuring the light intensity scattered forward from the angles of 4 degrees to 12 degrees by aerosol, and cloud particles that pass through a focussed laser beam.

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Gas monitors measure trace gases.

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The Global Change Observation Mission – Water Satellite 1 (GCOM-W) mission aims to establish the global and long-term observation system to collect data, which is needed to understand mechanisms of climate and water cycle variations, and demonstrate its utilization. The Advanced Microwave Scanning Radiometer 2 (AMSR2)  onboard the first generation of the GCOM-W satellite will continue Aqua/AMSR-E (Advanced Microwave Scanning Radiometer for EOS) observations of water vapor, cloud liquid water, precipitation, sea surface temperature (SST), sea surface wind speed, sea ice concentration, snow depth, and soil moisture.

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The GPM Cold-season Precipitation Experiment (GCPEx) occurred in Ontario, Canada during the winter season (Jan 15- Feb 26) of 2011-2012. GCPEx addressed shortcomings in GPM snowfall retrieval algorithms by collecting microphysical properties, associated remote sensing observations, and coordinated model simulations of precipitating snow. These data sets were collected toward achieving the overarching goal of GCPEx which is to characterize the ability of multi-frequency active and passive microwave sensors to detect and estimate falling snow. Instruments on airborne platforms, radars, ground based instruments and satellites collected data for this experiment. Collectively the GCPEx datasets provide a high quality, physically-consistent and coherent data set suited to the development and testing of GPM (Global Precipitation Measurement Mission) snowfall retrieval algorithm physics.

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The Genesis and Rapid Intensification Processes (GRIP) experiment was a NASA Earth science field experiment conducted 5 August - 30 September 2010 to better understand how tropical storms form and develop into major hurricanes. NASA used the DC-8 aircraft and the Global Hawk Unmanned Airborne System (UAS) configured with a suite of in situ and remote sensing instruments that were used to observe and characterize the lifecycle of hurricanes. This campaign also captilized on a number of ground networks and space-based assets, in addition to the instruments deployed on aircraft from Ft. Lauderdale, Florida (DC-8) and NASA Dryden Flight Research Center, California (Global Hawk).

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Device designed to determine the electrical conductivity of the atmosphere. By using a capacitor exposed to a sample of air and measuring the time it takes for discharge, the electrical conductivity of the sample is determined.

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Relating to the entire earth or other planet

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The NOAA Global Hawk In-flight Turbulence Sensor (GHIS) instrument measures acceleration at the location of the instrument. Two accelerometers (2g and 5g full scale) are used on each of two measurement axes. The GHIS accelerometers are from the Model 1221 family manufactured by Silicon Designs, Inc. with a frequency response of 400-600Hz. The data system samples each sensor output at 1000 Hz and processes these data to produce mean, maximum, and root-mean square (RMS) values at 10 Hz. The processed data are then broadcast on the GH internet and brought to the ground via Status and User UDP (User Datagram Protocol) packets.

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The Global Hawk is an Unmanned Aerial Vehicle (UAV) configured with in situ and remote sensing instruments for use in high-altitude, long-duration Earth science missions. The Global Hawk measures 44 feet in length, with a wingspan of 116 feet. NASA expects to operate the Global Hawk with payloads up to 2000 pounds and at altitudes up to 65,000 feet. Its range is greater than 10,000 nautical miles and its endurance is greater than 31 hours.

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Geostationary Meteorological Satellite (GMS) Program was Japan's contribution to the International Global Atmospheric Research Program and World Weather Watch and consisted of a series of geostationary spin-stabilized satellites stationed near 140 degrees East longitude.

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Geostationary Meteorological Satellite (GMS)-4 is a Japanese satellite (similar to Geostationary Operational Environmental Satellite (GOES)-7) in geostationary orbit over the equator at approximately 140E. The satellite is equipped with the Visible and Infrared Spin Scan Radiometer (VISSR) imaging sensor, which uses the spin motion of the satellite to scan the earth in the East-West direction. GMS begins a North-South scan every hour on the half hour, with four additional scans daily for wind estimation. At the satellite subpoint, the visible (0.5-0.75 um) channel has a resolution of 1.25 km (although, the Global Hydrology Climate Center (GHCC) archives a reduced resolution 5 km visible image) and the infrared (10.5-12.5 um) channel has a resolution of 5 km.

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The Global navigation satellite system (GNSS) is a commercial inertial solution for airborne direct georeferencing. Used with digital cameras and scanners it precisely measures aerial sensor position and orientation hundreds of times each second, accounting for all motion variables at the exact moment of data capture.

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Geostationary Operational Environmental Satellite system (GOES): A series of earth-synchronous United States satellites spaced in longitude over the equator in the western hemisphere to provide near-continuous observations of the earth and its atmosphere. GOES satellites 1-7 were spin stabilized, but are no longer in service. GOES 8-10 are 3 axis stabilized.

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Geostationary Operational Environmental Satellite (GOES)-10: the tenth in a series of U.S. satellites in earth synchronous orbit,launched April 25, 1997. It was retired in December of 2009.

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Geostationary Operational Environmental Satellite (GOES)-11: the 11th in a series of U.S. satellites in geostationary orbit over the equator in earth synchronous orbit. GOES-11 is presently in an active standby mode, and is not functioning. It was brought into operational status for the Tropical Cloud Systems and Processes (TCSP) mission, providing hurricane and tropical storm coverage for all of Central America. It was launched May 3, 2000 and retired in December of 2011.

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The GOES-11 imager is a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the earth. It provides near continuous observation (three axis stabilized staring imager) in the visible and infrared portions of the electromagnetic spectrum. At the satellite subpoint, the visible channel (0.55-0.75 um) has a spatial resolution of 1.0 km, the shortwave infrared channel (3.8-4.0 um) and two longwave infrared (10.2-12.5 um) channels have a resolution of 4 km, while the water vapor channel (6.7-7.0 um) has an 8.0 km resolution.

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Geostationary Operational Environmental Satellite (GOES)-12: the 12th in a series of U.S. satellites in geostationary orbit over the equator in earth synchronous orbit. Known as GOES-M it was launched on July 23, 2001 and its orbit as GOES-12 became effective on April 1, 2003. It was decomissioned in August 2013.

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The GOES-12 imager is a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the earth. It provides near continuous observation (three axis stabilized staring imager) in the visible and infrared portions of the electromagnetic spectrum. At the satellite subpoint, the visible channel (0.55-0.75 um) has a spatial resolution of 1.0 km, the shortwave infrared channel (3.76-4.03 um) and two longwave infrared (10.23-11.24 um) channels have a resolution of 4 km, while the water vapor channel (5.77-7.33 um) has an 4.0 km resolution. The CO2 channel (12.96-13.72 um wavelength) has a spatial resolution of 4 km. Comparing with GOES 11, GOES-12's Channel 3 has a different resolution, channel 5 has been lost and channel 6 has been added.

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Geostationary Operational Environmental Satellite (GOES)-13: the 13th in a series of U.S. satellites in geostationary orbit. over the equator in earth synchronous orbit. Known as GOES-N it was launched on May 24, 2006. ince April 14, 2010, GOES-13 has been the operational weather satellite for GOES-EAST and is still active.

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The GOES-13 Imager is a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the Earth. By means of a servo driven, two-axis gimbaled mirror scanning system in conjunction with a Cassegrain telescope, the Imager's multispectral channels can simultaneously sweep an 8-kilometer (5 statute mile) north-to-south swath along an east-to-west/west-to-east path, at a rate of 20 degrees (optical) east-west per second. This translates into being able to scan a 3000 by 3000 km (1864 by 1864 miles) "box" centered over the United States in just 41 seconds. The actual scanning sequence takes place by sweeping in an East-West direction, stepping in the North-South direction, then sweeping back in a West-East direction, stepping North-South, sweeping East-West, and so on.

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Geostationary Operational Environmental Satellite (GOES)-8: the eighth in a series of U.S. satellites in geostationary orbit over the equator in earth synchronous orbit. GOES-8 (also called GOES East) was launched April 13, 1994; it was stationed at 75W observing the Atlantic Ocean (providing hurricane and tropical storm coverage) and most of North and South America. It was retired May 4, 2004.

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The GOES-8 imager is a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the earth. It provides near continuous observation (three axis stabilized staring imager) in the visible and infrared portions of the electromagnetic spectrum. At the satellite subpoint, the visible channel (0.55-0.75 um) has a spatial resolution of 1.0 km, the shortwave infrared channel (3.8-4.0 um) and two longwave infrared (10.2-12.5 um) channels have a resolution of 4 km, while the water vapor channel (6.7-7.0 um) has an 8.0 km resolution.

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Geostationary Operational Environmental Satellite (GOES)-9: the ninth in a series of U.S. satellites in geostationary orbit over the equator in earth synchronous orbit. GOES-9 (also called GOES West) was launched May 23, 1995; it was stationed at 105W observing the Eastern Pacific Ocean and the United States. The GOES-9 imager was a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the earth. It provided near continuous observation (three axis stabilized staring imager) in the visible and infrared portions of the electromagnetic spectrum. At the satellite subpoint, the visible channel (0.55-0.75 um) had a spatial resolution of 1.0 km, the shortwave infrared channel (3.8-4.0 um) and two longwave infrared (10.2-12.5 um) channels had a resolution of 4 km, while the water vapor channel (6.7-7.0 um) had an 8.0 km resolution. GOES-9 was retired in June 2007.

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The GOES-9 imager is a five channel (one visible, four infrared) imaging radiometer designed to sense radiant and solar reflected energy from sampled areas of the earth. It provides near continuous observation (three axis stabilized staring imager) in the visible and infrared portions of the electromagnetic spectrum. At the satellite subpoint, the visible channel (0.55-0.75 um) has a spatial resolution of 1.0 km, the shortwave infrared channel (3.8-4.0 um) and two longwave infrared (10.2-12.5 um) channels have a resolution of 4 km, while the water vapor channel (6.7-7.0 um) has an 8.0 km resolution.

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The purpose of the Global Precipitation Climatology Project (GPCP) is to derive gridded data sets of monthly precipitation totals covering the entire globe based on all available observation technologies and data. Data are gathered at the Global Precipitation Climatology Center (GPCC) which operates under objectives defined by the World Climate Research Program (WCRP). The GPCP contributes data sets to the Global Energy and Water Cycle Experiment (GEWEX) and is expected to be a component of the Global Climate Observing System (GCOS).

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The Global Precipitation Measurement (GPM) Ground Validation (GV) Experiment is the ground-based component of the GPM mission which also includes satellite data. The GPM mission is to study global rain, snow and ice to better understand our climate, weather, and hydrometeorological processes. The ground instruments include disdrometers and rain gauges. The satellite data will extend the Tropical Rainfall Measuring Mission (TRMM)'s observations of precipitation to higher latitudes with more frequent sampling. GPM will be capable of measuring rain rates as small as a hundredth of an inch per hour to as large as 4 inches an hour. GPM will be able to estimate the various sizes of precipitation particles, and will also discriminate between snow and rain. GPM will seek to achieve these measurements with a 3-hour average revisit time over 80% of the globe, and the data will be available to users within 3 hours of observation time.

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Global Positioning System (GPS). A constellation of satellites in low earth orbit which provide information to receivers which then internally calculate their (the receivers) location in 3-dimentional space. Accuracy is within 10 meters.

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The Global Positioning System (GPS) clock.

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The Genesis and Rapid Intensification Processes (GRIP) experiment was a NASA Earth science field experiment conducted 5 August - 30 September 2010 to better understand how tropical storms form and develop into major hurricanes. NASA used the DC-8 aircraft and the Global Hawk Unmanned Airborne System (UAS) configured with a suite of in situ and remote sensing instruments that were used to observe and characterize the lifecycle of hurricanes. This campaign also captilized on a number of ground networks and space-based assets, in addition to the instruments deployed on aircraft from Ft. Lauderdale, Florida (DC-8) and NASA Dryden Flight Research Center, California (Global Hawk).

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Land surface observation site

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Measurement of phenomena made with instrumentation which is located at a specific point on the surface of the earth.

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The High Altitude Monolithic Microwave Integrated Circuit (MMIC) Sounding Radiometer (HAMSR) is a microwave atmospheric sounder developed by the Jet Propulsion Laboratory (JPL) under the NASA Instrument Incubator Program. Operating with 25 spectral channels in the 50-190 HGz region, it provides measurements that can be used to infer the 3-D distribution of temperature, water vapor, and liquid water in the atmosphere, even in the presence of clouds. HAMSR was mounted in a wing pod of a research aircraft

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Hierarchical Data Format (HDF) is a multi-object format that is designed to facilitate the sharing of data among people, project, and machines on a network. Public domain software from HDF at the National Center for Supercomputing Applications (NCSA).

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The amount of heat entering a specified cross-sectional area of a surface per unit time.

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The Hurricane Imaging Radiometer (HIRAD) is a hurricane imaging, single-pol passive C-band radiometer with both cross-track and along-track resolution that measures strong ocean surface winds through heavy rain from an aircraft or space-based platform. Its swath width is approximately 60 degrees in either direction. It provides unique observations of sea surface wind, temperature, and rain.

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The High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) is a dual-frequency (Ka- and Ku-band) conical scan system, configured with a nadir viewing antenna on the high-altitude (20 km) NASA ER-2 aircraft. The HIWRAP is able to measure line-of-sight and ocean surface winds at higher spatial and temporal resolution than obtained by current satellites and lower-altitude instrumented aircraft.

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Graph of a scalar quantity, horizontal wind magnitude/speed or direction, vs. the vertical height.

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A human being who observes, measures, and records scientific data in the absence of more precise or automated means.

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A measure of the water-vapor content of air.

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Humidity sensors are devices that receive a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it, in this case humidity or some measure of the water vapor content of air.

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A hurricane mission report is a short in-field science report that has high level information about a campaign's daily mission. It normally includes the mission date, sortie number(s), a mission description, mission objective, mission notes, and a summary of ground/other assets. It is written by the mission scientist in charge of that day'Smission.

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Severe tropical cyclones having winds in excess of 64 knots (74 mi/hr).

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The High Volume Precipitation Spectrometer (HVPS) measures particle size and operates by taking a two-dimensional shadow digital picture of the particles that pass through a 4.5 x 20.3 cm laser light plane that is normal to the direction of aircraft flight. The sheet of light is imaged onto a linear array of 256 photo-elements.The HVPS has 200 mm pixel resolution when measured across the array.

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Particles in the atmosphere composed of water, e.g. ice, raindrops, snow, etc.

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An instrument designed to measure absolute and relative humidity of the atmosphere.

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The Iowa Flood Studies (IFloodS) Field Experiment, as part of the Global Precipitation Measurement Mission (GPM), was conducted in the central to the northeastern part of Iowa during the months of April-June 2013. Its purpose was to provide better understanding of the strengths and limitations of satellite products in the context of hydrologic applications. Goals included the quantification of physical characteristics and space/time variability of rain (rates, drop size distribution (DSD)) mapped to satellite rainfall retrieval uncertainty; assessment of satellite rainfall retrieval uncertainties at instantaneous to daily time scales to evaluate propagation/impact of uncertainly in flood-prediction; assessment of hydrologic predictive skill as a function of space/time scales, basis morphology and land use/cover; discernment of the relative roles of rainfall quantities (e.g., rate and accumulation) as compared to other factors (e.g., transport in drainage) in flood genesis; and refinement of approaches to "integrated hydrologic Ground Validation (GV)" concept based on IFloodS experiences to apply to future GPM integrated field efforts.

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Imagery created in the portion of the electromagnetic spectrum. The Infrared (IR) region of the spectrum has wavelengths between approximately .75 microns to 100 microns, but imagery created using meteorlogical satellites typically is created using the 10-12.5 micron portion of the spectrum. This 'window' is relatively transparent to infrared radiation.

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A device which allows contact less temperature measure by the use of infrared radiation.

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Upwelling radiation in the infrared portion of the electromagnetic spectrum which is observed by the spacecraft instrumentation.

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An instrument for measuring longwave radiation (between visible and microwave spectrum) lying in the wavelength interval from about 0.75 microns to approximately 100 microns.

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Inertial Navigation System (INS). Using a series of orthogonally mounted accelerometers which detect changes from straight line motion, this device provides a self contained and independent method by which it can determine positional changes from a starting point. INS units are extensively used in spacecraft, ships and aircraft.

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A measure of the columnar water vapor in the earth's atmosphere in grams per square centimeter.

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The Global Precipitation Measurement (GPM) Ground Validation (GV) Integrated Precipitation and Hydrology Experiment (IPHEx) was held in North Carolina during the months of April-June 2014. IPHEx seeks to characterize warm season orographic precipitation regimes, and the relationship between precipitation regimes and hydrologic processes in regions of complex terrain. The IPHEx focus includes the development, evaluation and improvement of remote-sensing precipitation algorithms in support of the GPM mission through NASA GPM GV field campaign (IPHEX_GVFC) and the evaluation of Quantitative Precipitation Estimation (QPE) products for hydrologic forecasting and water resource applications in the Upper Tennessee, Catawba-Santee, Yadkin-Pee Dee and Savannah river basins: Hydrologic Modeling/Forecasting for the Southeast (IPHEX-HAP, H4SE). NOAA Hydrometeorology Testbed (HTM) has synergy with this project.

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The Infrared (IR) region of the spectrum has wavelengths between approximately .75 microns to 100 microns.

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JACKSONVILLE 90 was a NASA mission consisting of flights conducted during October 1990 over the Gulf of Mexico. These early validation flights collected data from the Advanced Microwave Precipitation Radiometer (AMPR) which were used develop algorithsm relating to brightness temperaters observed at different wavelenghts to precipition charactersitics.The Lightning Instrument Package (LIP) instrument also partiipated in the mission.

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The Joss-Waldvogel (JW) disdrometer is an impact-type electromechanical counter designed to measure the drop size distribution (DSD).

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The Laser Hygrometer measures in situ water vapor content using a tuneable laser emitting at 1.37 microns. Absorption at that wavelength is a function of water vapor content. Measuring the amount of absorption in an open path beyond the aircraft boundary layer, a value of water vapor pressure is made. The maximum sampling rate is 8 Hz, but the instrument is normally configured through the software for a 1Hz sampling rate.

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The PMS (Particle Measuring System) King Probe uses the direct measurement of the power changes in a heated wire assembly needed to evaporate impacted water droplets to measure total liquid water content.

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The KSC (Kennedy Space Center) Field Mill Network (also known as the Advanced Ground Based Field Mill (AGBFM) Network) is a system of instruments called field mills. Each field mill detects the overhead electrostatic field strength using stainless steel plates (stators) which are alternatively shielded and exposed to the existing atmospheric electric field by a grounded rotor. The data are recorded at a rate of 50 Hz at a 4V/m sensitivity. Fields of up to +-32kV/m can be recorded with the higher readings corresponding to an intense thunderstorm overhead. The sign convention corresponds to atmospheric potential gradient where the fair weather field is positive.

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KWAJEX: The Kwajalein Experiment is part of the Tropical Rainfall Measuring Mission, TRMM, whose goals include providing Ground Validation, GV, for instruments onboard the TRMM satellite launched in November of 1997. KWAJEX was the only TRMM campaign designed to be conducted over the tropical open ocean, and was conducted between 30 July and 14 September 1999.

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The Land Atmosphere Near real-time Capability for EOS (LANCE) makes EOS data from MODIS (Moderate Resolution Imaging Spectroradiometer), AIRS (Atmospheric Infrared Sounder), MLS (Microwave Limb Sounder), and OMI (Ozone Monitoring Instrument) available within three hours of satellite overpass to meet the timely needs of applications such as numerical weather and climate prediction; forecasting and monitoring natural hazards, ecological/invasive species, agriculture, and air quality; providing help with disaster relief; and homeland security.

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The characterization of land by specific surface types such as desert, dense vegetation, and arable soil.

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A measure of the thermal energy of the land surface.

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Landsat-5 is the fifth satellite of the Landsat program. It was launched on March 1, 1984, with the primary goal of providing a global archive of satellite photos. It is a circular, sun-synchronous, near-polar orbit at an altitude of 705 km (438 mi), inclined at 98.2 degrees with swath width of 185 km (115 mi). It repeats every 232 orbits, or 16 days with equatorial crossing time of 9:45 a.m. +/- 15 minutes. It carried the Multispectral Scanner (MSS) which was turned off in August of 1995, but continues to carry the Thematic Mapper (TM). More information can be found on Landsat-5 can be found at http://landsat.gsfc.nasa.gov/?p=3180

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Landsat 7, launched on April 15, 1999, is the latest satellite of the Landsat program. Landsat 7's primary goal is to refresh the global archive of satellite photos, providing up-to-date and cloud-free images. Landsat 7 was designed to last for five years, and has the capacity to collect and transmit up to 532 images per day. It is in a polar, sun-synchronous orbit, meaning it scans across the entire earth's surface. With an altitude of 705 kilometres +/- 5 kilometres, it takes 232 orbits, or 16 days, to do so. More information on Landsat 7 can be found at http://landsat.gsfc.nasa.gov/?p=3184

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The Vaisala LAP 3000 is a pulsed Doppler radar which provides continuous and real-time vertical profiles of horizontal wind speed and direction and radial velocity up to 3 km above ground level.

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LASE (Lidar Atmospheric Sensing Experiment) is an airborne DIAL (Differential Absorption Lidar) system used to measure water vapor, aerosols, and clouds throughout the troposphere. LASE operates by locking to a strong water vapor line and electronically tuning to any spectral position on the absorption line to choose the suitable absorption cross-section for optimum measurements over a range of water vapor concentrations in the atmosphere.

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The Laser Absorption Spectrometer (LAS) is an autonomous instrument based on off-axis integrated cavity output spectroscopy used to measure in-situ carbon monoxide mixing ratios and to derive mixing ratio profiles.

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The Laser Hygrometer measures in situ water vapor content using a tuneable laser emitting at 1.37 microns. Absorption at that wavelength is a function of water vapor content. Measuring the amount of absorption in an open path beyond the aircraft boundary layer, a value of water vapor pressure is made. The maximum sampling rate is 8 Hz, but the instrument is normally configured through the software for a 1Hz sampling rate.

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Raw instrument data at original resolution, time ordered, with duplicate packets removed.

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Reconstructed unprocessed instrument data at full resolution, time referenced, and annotated with ancillary information, including radiometric and geometric callibration coefficients and georeferencing parameters (i.e., platform ephemeris) computed and appended, but not applied to Level 0 data.

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Radiometrically corrected and geolocated Level 1A data that have been processed to sensor units.

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Derived geophysical parameters at the same resolution and location as the Level 1 data.

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Geophysical parameters that have been spatially and/or temporally re-sampled (i.e., derived from Level 1 or Level 2 data).

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Model output and/or results of lower level data that are not directly derived by the instruments.

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The Licor Gas Exchange System measures photosynthesis, fluorescence and soil CO2 flux.

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The laser light energy that is reflected back to a detector.

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The large spark produced by an abrupt discontinuous discharge of electricity through the air, resulting most often from the creation and separation of electric charge in cumulonimbus clouds.

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Lightning Detection and Ranging (LDAR) is a system of antennas which upon receiving a lightning generated radio frequency signal calculates the location in three dimensional space and the amplitude of the signal. With reference to the GHRC data sets, LDAR specifically refers to the system in place at the Kennedy Space Center used for basic research and support of Space Shuttle operations.

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The total observed luminous phenomenon accompanying a lightning discharge.

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The rate of observed luminous phenomenon accompanying a lightning discharge.

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The Lightning Nitrogen Oxides Model (LNOM) is NASA software which combines detailed, flash-specific measurements of lightning with empirical laboratory results and theoretical results in order to make estimates of the amount of nitrogen oxides (NOx = NO + NO2) produced by both ground and cloud flashes. The vertical lightning NOx profile inside the LNOM analysis cylinder is obtained for the analysis period (typically 1 month), and the total NOx produced by each flash is also obtained. Flashes (or portions of a flash) falling outside the LNOM analysis cylinder do not contribute to the vertical NOx profile within the LNOM analysis cylinder. All NOx amounts are provided in moles.

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A lightning stroke is an individual discharge of a lightning flash. The term lightning flash is used to describe the entire discharge, which takes on the order of 0.2 seconds. But a flash is usually made up of several shorter discharges (strokes) which last less than a millisecond and which repeat rapidly enough that the eye cannot resolve the multiple events.

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The Lightning Instrument Package (LIP) consists of an average of 6 rotating vane type electric field sensors, a dual channel conductivity probe, slow and fast antennas, and two optical sensors along with a central computer to record and monitor the instruments. The actual configuration varies depending on the specific platform's resources. The electric field sensors are standard in each field campaign with the conductivity probe present in most experiments. The slow and fast antenna and optical sensors are included when the configuration allows. Each field mill incorporates self-calibration capabilities that reduce the time required to obtain a full aircraft calibration. In addition, the electric field signals are digitized at each mill and transmitted as a digital data stream, reducing signal noise and simplifying aircraft integration. The electric field mills and the conductivity probe are compact sensors, each weighing less than 10 lbs and provide the full vector components of the atmospheric electric field (i.e., Ex, Ey, Ez) around the storms overflown. The air conductivity probe determines the electrical conductivity of the atmosphere and can be used to derive storm electrical currents. Slow and fast antennas acquire lightning waveforms and provide a measure of total lightning. Dual multiple channel, calibrated, optical sensors are used to determine the intensity, duration, and waveform characteristics of the different types of lightning discharges from thunderstorms.

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The liquid water present within a sample of snow (or soil), usually expressed in percent by weight.

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The equivalent amount of liquid water contained in water vapor per unit volume of air.

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The liquid water in any region, cloud or no cloud, based upon the physically based method of Greenwald et al.(1993) for ocean areas only. Usually measured in milligrams per square centimeter.

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The Lightning Imaging Sensor (LIS) is an optical staring telescope on the Tropical Rainfall Measuring Mission (TRMM) satellite designed as an on orbit lightning detector functioning in day or night conditions. With a field of view of 600x600 kilometers, a resolution of 10 kilometers and imaging every 2 milliseconds (500 images per second) at 777 microns, the on board software compares successive images. Brightness changes between successive images satisfying specified criteria are located both temporally and spatially, and reported to the LIS Science Computing Facility at the Marshall Space Flight Center (MSFC). A spare LIS instrument was built for the TRMM program and was carefully stored for future use. NASA found a very important use for LIS, and it was placed on the International Space Station (ISS) in Feb 2017. Since the space station has a highly inclined orbit, a greater geographic range of measurements are obtained than previously measured by TRMM LIS. On the ISS, LIS provides total lightning measurements between +/- 55 degrees latitude which covers a geographic range that includes nearly all global lightning.

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Lightning Imaging Sensor (LIS) Validation is the verification and validation process numerical models and simulation, and statistical and objective analyses. It verifies performance, algorithms, products inspecting accuracy, resolution, ,and variabilty in order to improve the instrument and products

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Marshall Space Flight Center internal inventory table used for cataloging metadata

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Energy radiated or transmitted in the wavelengths longer than 4 micrometers portion of the spectrum.

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Long Range Navigation system

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Line-of-Sight (LOS) winds. Measures the vector projection of the true 3-D wind into the direction of the pulsed laser beam, determined by the frequency change of the returned light due to the Doppler shift.

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Atmospheric temperature from 150 hPa to 30 hPa (rather than from the tropopause to an altitude of 20 km).

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Atmospheric temperature from the earth's surface to 500 hPa (rather than to 10km).

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The Light Precipitation Evaluation Experiment (LPVEx), part of the Global Precipitation Measurement Project (GPM), took place in September and October 2010 in the Gulf of Finland to characterize the ability of CloudSat, the GPM Dual-frequency Precipitation Radar (DPR), and existing/planned passive microwave (PMW) sensors such as the GPM microwave imager (GMI) to detect light rain and evaluate their estimates of rainfall intensity in high latitude, shallow freezing level environments. The experiment leveraged in situ microphysical property measurements, coordinated remote sensing observations, and cloud resolving model simulations of high latitude precipitation systems to conduct a comprehensive evaluation of precipitation algorithms for current and future satellite platforms. The campaign used these measurements to better understand the process of light rainfall formation at high latitudes and augmented the limited database of light rainfall microphysical properties that formed the critical assumptions at the root of satellite retrieval algorithm.

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A device which uses light at 121.6 nm (also known as Lyman-alpha light) to photodissociate water in a sample chamber to produce excited OH radicals. The fluorescence from these radicals at 309 nm is detected with a phototube and counting system yielding the total water amount in the sample.

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The Multicenter Airborne Coherent Atmospheric Wind Sensor (MACAWS) is an eye-safe Dopller laser radar (lidar) operating at 10/6 microns. Line of sight velocity and intensity are measured by backscattering from windborne aerosols, clouds, land and water surfaces.

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The magnaprobe is a GPS equipped snow depth probe.

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Pertaining to the magnetic field generated by the Earth, consisting of both the dipole and non-dipole components.

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Multispectral Atmospheric Mapping Sensor (MAMS) measures reflectd radiation from the Earth's surface and clouds in eight visible/near-infrared bands, and thermal emission from the Earth's surface, clouds, and atmospheric constituents (primarily water vapor) in four infrared bands.

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The quantification of a physical variable by interpolation/extrapolation of a previously mapped parameter field.

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Loose particles of inorganic or organic origin, suspended in the water column, found on the seafloor, or found in the coastal zone. Variables include types of sediment, processes affecting sediment and sediment distribution, and characteristics of sediment.

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Scalar value of the magnitude of the wind speed at the ocean surface, usually measured in meters per second.

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MODerate resolution Imaging Spectroradiometer (MODIS) Airborne Simulator.

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The Midlatitude Continental Convective Clouds Experiment (MC3E) took place in central Oklahoma during the April-June 2011 period. The experiment was a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration's (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leveraged the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal was to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that had never before been available.

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The mean reflectivity weighted motion along the radar beam with positive motions approaching the radar.

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The average streamflow over a period of time, where streamflow is defined as the rate of water flowing in a channel, usually measured in cubic feet per second.

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Mesoscale Meteorological Network (MESONET) is a system of world-class network of environmental monitoring stations that gather current meteorological observations and send the data to their corresponding centers.

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A fixed, above-ground station that is used to collect and/or transmit meteorological data.

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Stations that observe and monitor variables such as temperature, atmospheric pressure, humidity, surface winds, precipitation, radiation, visibility, evaporation, and current conditions.

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Meteosat is a contribution of the European Space Agency (ESA) to the Global Atmospheric Research Program's World Weather Watch which consisted of a series of geostationary, spin-stabilized satellites (similar to GOES (Geostationary Operational Environmental Satellite) and GMS (Geostationary Meteorological Satellite) stationed near 0 degrees East).

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METEOSAT-6 is the sixth in a series of geostationary, spin-stabilized satellites (similar to GOES-7 (Geostationary Operational Environmental Satellite - 7) and GMS-4 (Geostationary Meteorological Satellite - 4)) stationed near the prime meridian above the equator to provide continuous observations of earth's environment in both visible and infrared portions of the electromagnetic spectrum. The visible channel has a 2.5 km spatial resolution and the infrared channel has a 5.0 km resolution. METEOSAT-6 was launched November 20, 1993, and its current status is inactive

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METEOSAT-7 is the last of the series of first generation geostationary, spin-stabilized satellites (similar to GOES-7 (Geostationary Operational Environmental Satellite - 7) and GMS-4 (Geostationary Meteorological Satellite - 4)) stationed near the prime meridian above the equator to provide continuous observations of earth's environment in both visible and infrared portions of the electromagnetic spectrum.2.5 km spatial resolution and the infrared channel has a 5.0 km resolution. METEOSAT-7 was launched September 7, 1997, and its current status is inactive.

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METEOSAT-9, a Meteosat Second Generation (MSG) geostationary weather satellite launched December 21, 2005, is located 35,800 (22,300 statue miles) above the equator at 0 degrees E, just west of Africa. It provides coverage of Europe, Africa, the Middle East, eastern portions of South America and the Atlantic Ocean and western portions Indian Ocean. The standard mode of operation is full-disk imagery in 12 spectral channels every 15 minutes. The geostationary satellites are the only source of meteorological data over open oceans. The MSG serves the needs of Nowcasting applications and Numerical Weather Prediction for climate monitoring and research with major improvements of services through 12 spectral bands of its radiometer, the Spinning Enhanced Visible and InfraRed Imager (SEVIRI). In addition to the SEVIRI, the MSG satellites carry the Geostationary Earth Radiation Budget (GERB) instrument, which provides valuable data on reflected solar radiation and thermal radiation emitted by the Earth and atmosphere. METEOSAT-9 is currently operational.

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The amount of methane released by wetlands into the atmosphere, usually measured as an annual total.

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The MicroLab-1 spacecraft was built and successfully launched on April 3, 1995 by Orbital Sciences Corporation (OSC). MicroLab-1 spacecraft carries the Optical Transient Detector (OTD), sponsored by NASA's Marshall Space Flight Center. The spacecraft was launched into a 70 degree inclination orbit at an altitude of 740km and has a system life of 2 years. MicroLab-1 was renamed OrbView in 1997.

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The Micro Pulse Lidar (Light Detection and Ranging) is a compact and eye-safe lidar system capable of determining the range of aerosols and clouds in the atmosphere by firing a short pulse of laser light (at 523nm). This instrument is also a part of the global Micro-Pulse Lidar Network (MPLNET).

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A reproduction of an object by imaging the microwave radiation coming from the object or reflected by the object.

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In radiometery, a measure of the intrinsic radiant intensity emitted by a radiator in a given direction. Radiance is measured in watts per square meter and steradian.

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The Microwave Profiling Radiometer (MPR) is a 12 channel microwave radiometer that measures profiles of temperature, water vapor, cloud water, and integrated values of water vapor and cloud water at 10 minute intervals up to 10 km with the highest vertical resolution at low levels.

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The Microwave Temperature Profiler (MTP) is a passive microwave radiometer which measures the thermal emmission from oxygen molecules in the atmosphere for a selection of elevation angles. Measured brightness temperatues versus elevation angle is converted to air temperature versus altitude using a statistical retrieval procedure.

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The University of Alabama in Huntsville (UAH) Mobile Integrated Profiling System (MIPS) is a mobile atmospheric profiling system. It includes a 915 MHz Doppler profiler, lidar ceilometer, 12 channel microwave profiling radiometer, Doppler Sodar, Radio Acoustic Sounding System (RASS), Field Mills, and asurface observing station.

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A mission report is a short in-field science report that has high level information about a campaign's daily mission. It includes the mission date, sortie number(s), a mission description, mission objective, mission notes, and a summary of ground /other assets. It is written by the mission scientist in charge of that day's mission.

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The analysis of model derived fields.

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A mathematically derived product which is based on physical and/or empirical principles.

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A model is the process of providing to a computer, usually in the form of mathematical equations, a precise and unambiguous description of a system including the relationships between system inputs and outputs, and using this description to simulate. Analyses may be generated from a scientific study or computer analyses.

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MODerate-resolution Imaging Spectroradiometer (MODIS), aboard the TERRA (EOS AM-1) spacecraft, is a whisk broom scanning radiometer that will view the entire Earth's surface every 1 to 2 days, acquiring data in 36 spectral bands (0.4 - 14.4 um) at moderate resolution (0.25 - 1 km). MODIS has a viewing swath of 2330 km (field of view sweeps +/- 55 degrees cross-track) and will provide high-radiometric resolution images of daylight-reflected solar radiation and day/night thermal emissions over the globe. Its spatial resolution ranges from 250 m to 1 km at nadir.

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MODerate resolution Imaging Spectroradiometer (MODIS) Airborne Simulator.

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A record of moisture at a specific geographic location.

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The Micro Rain Radar (MRR) is a frequency-modulated continuous wave (FMCW) vertically pointing Doppler radar, which operates at 24.24GHz and provides vertical profiles of drop size distribution. The MRR is the second generation of the instrument manufactured by METEK (URL: http://metek.de/product-group/micro-rain-radar-24-ghz/).

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Meteosat Second Generation (MSG) consists of a series of four geostationary meteorological satellites, along with ground-based infrastructure, that will operate consecutively until 2020. The MSG system is established under cooperation between The European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) and the European Space Agency (ESA) to ensure the continuity of meteorological observations from geostationary orbit. The MSG satellites carry an impressive pair of instruments, the Spinning Enhanced Visible and InfraRed Imager (SEVIRI), which has the capacity to observe the Earth in 12 spectral channels and provide image data which is core to operational forecasting needs, and the Geostationary Earth Radiation Budget (GERB) instrument supporting climate studies.

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Microwave Sounding Unit (MSU) is a 4 frequency passive microwave radiometer measuring oxygen absorption in 4 layers of the atmosphere to retrieve temperature profiles and rainfall over the oceans.

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Marshall Space Flight Center internal inventory table used for cataloging metadata

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The Microwave Temperature Profiler (MTP) is a passive microwave radiometer which measures the thermal emmission from oxygen molecules in the atmosphere for a selection of elevation angles. Measured brightness temperatues versus elevation angle is converted to air temperature versus altitude using a statistical retrieval procedure.

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The Multi-functional Transport Satellite (MTSAT)-1R is a three axis body stablized geostationary spacecraft that was launched 26 February 2005 and is planned to be operational through 2010. The MTSAT provides information to 27 countries and territories in the region, including 1) imagery for monitoring the distribution/motion of clouds, 2) sea surface temperature, and 3) distribution of water vapor. The MSTSAT series replaced the Geostationary Meteorological Satellite (GMS) series that had been in operation since 1977. It has taken over the role of the GMS series, covering East Asia and the Western Pacific region from 140 degrees east and 35,800 km above the equator. The MTSAT series provides imagery for the Northern Hemisphere every 30 minutes. The MTSAT series carries a new imager with a new infrared channel (IR4) in addition to the four channels (VIS (Visible)< IR1, IR2, and IR3) of the GMS-5.

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A sensor aboard Landsats 1-5 which acquires images of the earth for 4 bands. The resolution for all bands is 79 meters, and the approximate scene size is 170 km north-south by 185 km east-west (106 miles by 115 miles).

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No

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Not Applicable

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The NASA African Monsoon Multidisciplinary Analyses (NAMMA) campaign is a field research investigation sponsored by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). This mission was based in the Cape Verde Islands, 350 miles off the coast of Senegal in west Africa. Commencing in August 2006, NASA scientists employed surface observation networks and aircraft to characterize the evolution and structure of African Easterly Waves (AEWs) and Mesoscale Convective Systems over continental western Africa, and their associated impacts on regional water and energy budgets. NASA also made extensive use of its orbiting satellites (including Aqua, TRMM (Tropical Rainfall Measuring Mission), and the recently-launched Cloudsat/CALIPSO (Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations)) and modeling capabilities to improve its forecasts and flight plans.

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NASA owned McDonnell Douglas DC-8 aircraft is a four engined swept wing jet airplane which flies in the upper troposphere and lower stratosphere, and is used as an instrument platform for scientific experiments.

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The NASA ER-2 (Earth Resources 2) is a high altitude aircraft almost identical to the the United States Air Force (USAF) U-2 (Utility2) aircraft which flies at a cruise altitude of approximately 60,000 ft. The ER-2 is used by NASA as a platform for various airborne research.

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The weather reconnaissance WB-57 is a mid-wing, long-range aircraft capable of operation for extended periods of time from sea level to altitudes well in excess of 60,000 feet. This aircraft is primarily used for high altitude weather research.

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The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Aircraft Sounder Testbed Interferometer (NAST-I) is a high resolution Michelson interferometer which scans the earth in the infrared portion of the spectrum. Data gathered is used to remotely obtain temperature and moisture profiles of the atmosphere below the aircraft.

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NAST-MTS: The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Aircraft Sounder Testbed (NAST) Microwave Temperature Sounder (MTS) contains two microwave radiometer systems covering the spectral ranges of 50-56 GHz with eight single-sideband channels, and 115-123 Ghz with nine double-sideband channels centered on the 118.75 Ghz oxygen line. Both radiometers scan +- 65 degrees from nadir and also view two black-body targets and zenith for calibration. The temperature weighting functions cover altitudes from the surface to ER-2 altitude. A video camera in the MTS package provides ancillary digitized stereo images for cloud location.

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The National Lightning Detection Network (NLDN) is a commercial lightning detection network of about 130 antennae which are connected to a central processor that records the time, polarity, signal strength, and number of strokes of each cloud-to-ground lightning flash detected over the United States.

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Non-Standard format as provided by data producer.

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An apparatus used to measure the size and concentration of particles in a liquid by analysis of light.

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A measure of the total radiation minus that portion that is scattered and reflected.

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An instrument that measures the difference between the incoming and outgoing hemispheric radiation on a horizontal plane over the 0.4 to 4.0 micrometer waveband.

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The Nevzorov probe is a constant temperature hot wire probe and consists of two separate sensors for measuring the total water content (liquid water [which includes frozen species] content, LWC, and total water content, TWC) of clouds and fog in the range between 0.003 gm-3 and 3 gm-3.

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NEXRAD (Next Generation Radar) is the next generation of weather radar technology that is operational at 158 sites throughout the United States and at selected overseas locations. Meteorologists can now warn the public to take shelter with more notice than any previous radar. The maximum range of the NEXRAD radar is 250 nautical miles. The NEXRAD network provides significant improvements in severe weather and flash flood warnings, air traffic safety, flow control for air traffic, resource protection at military bases, and management of water, agriculture, forest, and snow removal. The NEXRAD is capable of operating in three different modes, Precipitation mode, Clean air Mode, and Severe weather mode. The radar is placed in precipitation mode when a significant amount of precipitation is detected. It completes nine full scans at different elevation angles between 0.5 and 19.5 degrees and is updated every six minutes. The NEXRAD offers much more resolution in precip levels. Old radars only had six precip levels, the NEXRAD has fifteen levels, which enables it to give more accurate descriptions on the intensity of precipitation.

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NIMBUS satellites were second-generation meteorological Research and Development spacecraft designed to serve as stabilized, near-polar, earth-oriented platforms for testing of advanced systems to sense and collect meteorological data.

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NIMBUS-7 was seventh in a series of meteorological Research and Development satellites designed to serve as stabilized, near-polar, earth-oriented platforms fortesting of advanced systems to sense and collect meteorological, oceanographic, and pollution data. It was launched on October 25, 1978, and had a crossing time of approximately 12 AM/PM. Operation of the NIMBUS-7 ended in 1967.

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A colorless gas, formula NO, the most common form of nitrogen emitted into the atmosphere, either by fuel combustion or due to natural emissions.

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A brown gas, formula NO₂, found at all levels in the atmosphere.

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The National Oceanic and Atmospheric Administration

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The National Oceanic and Atmospheric Administration (NOAA) owned Lockheed WP-3D is a four engined turboprop aircraft that is used for weather reconnassince in the troposphere and is used as an instrument platform for scientific experiments. The WP-3D was derived from the US Navy P-3 Orion and is known as "Hurricane Hunter."

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National Oceanic and Atmospheric Administration-10: Tenth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-10 was launched September 17, 1986 and had a crossing time of approximately 7:30 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-11: Eleventh in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-11 was launched September 24, 1988 and had a crossing time of approximately 1:40 AM/PM. Its current status is inactive

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National Oceanic and Atmospheric Administration-12: Twelfth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-12 was launched May 14, 1991 and has a crossing time of approximately 7:30 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-14: Fourteenth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-14 was launched December 30, 1994 and had a crossing time of approximately 1:40 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-15: Fifteenth in a series of polar orbiting meteorological satellites. NOAA-15 was launched May 13, 1998 and has a crossing time of approximately 7:30 AM/PM. It is currently still active.

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National Oceanic and Atmospheric Administration-16: Second in a series of five of Advanced TIROS N (Television InfraRed Operational Satellite - Next-generation) series of polar orbiting satellites (NOAA-K, L, M, and N; it includes the AMSU-A instrument and various other instruments. NOAA-16 was launched September 21, 2000 and had a a crossing time of approximately 2 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-17: Third in a series of five of Advanced TIROS N (Television InfraRed Operational Satellite - Next-generation) series of polar orbiting satellites (NOAA-K, L, M, and N) and it will provide improved imaging and sounding capabilites and operate over the next ten years. NOAA-17 was launched June 24,2002 and had a crossing time of approximately 10 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-18: Eighteenth in a series of polar orbiting, meteorological satellites. NOAA-18 was launched May 20, 2005 and has a crossing time of approximately 2 AM/PM. It is currently operational.

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National Oceanic and Atmospheric Administration-6: Sixth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-6 was launched June 27, 1979 and had a crossing time of approximately 7:30 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-7: Seventh in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-7 launched June 23, 1981 and had a crossing time of approximately 2:30 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Aministration-8: Eighth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-8 was launched March 28, 1983 and had a crossing time of approximately 7:30 AM/PM. Its current status is inactive.

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National Oceanic and Atmospheric Administration-9: Ninth in a series of third generation polar-orbiting, meteorological satellites that operate in pairs in orbits that are 90 degrees apart. NOAA-9 was launched December 12, 1984 and had a crossing time of approximately 2:20 AM/PM. Its current status is inactive.

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A joint program to generate consistent, stably calibrated, long time-series data sets from existing archives of operational satellite data, and to make these data readily available to the earth science community.

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NOXP, a NOAA X-band Polarimeteric radar,  is a mobile Doppler radar that operates on a 3cm wavelength (X-Band). This wavelength is more sensitive to smaller particles than the longer wavelengths used by NOAA NWS radars, and is capable of detecting tiny water droplets or snowflakes.

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National Polar-orbiting Operational Environment Satellite System (NPOESS)

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The NASA S-band Dual Polarimetric Radar (NPOL) is a Doppler scanning radar operating in the S bandwith horizontal and vertical polarization. Used for detection and detailing wind direction/velocities in the x, y and z direction as well as precipitation reflectivities.

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NASA water VAPor (NVAP) Inventory (INV): Marshall Space Flight Center internal inventory table used for cataloging metadata

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The National Weather Service's network of ground-based radars located throughout the United States.

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Scalar value of the magnitude of the wind speed at the ocean surface, usually measured in meters per second.

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The Operational Linescan System (OLS) is the primary sensor on the Defence Meteorological Satellite Program (DMSP) satellite series. The OLS provides global coverage in the visible and infrared wavelength bands.

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OMEGA was the first global-range radio navigation system operated by the United States in cooperation with six partner nations. It enabled ships and aircraft to determine their position by receiving very low frequency (VLF) radio signals in the range 10 tro 14kHz, transmitted by a network of fixed terrestrial radio beacons, using a receiver unit. It became operational around 1971 and was shut down in 1998 in favor of the Global Positionsing Satellte system. [Source: Wikipedia]

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On-line storage

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Operational Navigation Chart (ONC) maps are prepared by the Defense Mapping Agency of the Department of Defense for use by pilots; they include a large amount of information about natural and anthropogenic surface features. Primary source materials are larger-scale World Aeronautical Charts (WAC), prepared by the same agency. The WAC series is prepared almost exclusively from aerial photography, complemented in some regions by detailed local maps. ONC maps indicate innundation with overprint symbols.

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A high time resolved optical pulse sensor with a very wide field of view (FOV) (50deg), an all sky detector, a video camera with VCR tape storage, and associated data acquisition systems for the optical pulse sensors.

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The Optical Transient Detector (OTD) is an orbiting optical sensor that detects, locates, and measures the radiant energy of intra-cloud and cloud-to-ground lightning events over the earth during both day and night. The OTD is a scientific payload on the Microlab-1 low earth orbiting satellite.

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The concentration of a blue gaseous allotrope of oxygen, O₃, formed naturally from diatomic oxygen by electric discharge or exposure to ultraviolet radiation; is an unstable, powerfully bleaching, poisonous oxidizing agent with a pungent, irritating odor.

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The ozone number density is determined using the ozone absorbtion cross secion at 254nm in a closed chamber of known volume.

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A digital recording of a particle.

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A device that records the two dimensional shadows of particles as they pass through a focussed laser beam.

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Solid or liquid matter found in the air.

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Marshall Space Flight Center internal inventory table used for cataloging metadata

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An instrument used to measure luminous intensity, illumination, and other photometric quantities.

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The Precipitation Imaging Probe (PIP) is an optical spectrometer that measures the size and shape of particles from 100 micrometers to 6200 micrometers. It is the classic airborne 2-Dimensional imaging probe, with the expanded capability of the 64-element diode array and fast Digital Signal Processing electronics.

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A device consisting of two parts, a pitot tube and a static port. The pitot tube is an open tube aimed into the direction of flight which allows air to flow into it thus measuring total pressure. The static port is aligned so that air flows across, not into, the port. This measures static pressure of the air. The arithmetic difference of the two measured pressures (P_Total - P_Static) is used to determine airspeed.

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Pitot-Static system is a device consisting of two parts, a pitot tube and a static port. The pitot tube is an open tube aimed into the direction of flight which allows air to flow into it thus measuring total pressure. The static port is aligned so that air flows across, not into, the port. This measures static pressure of the air. The arithmetic difference of the two measured pressures (P_Total-P_Static) is used to determine indicated airspeed.

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The height of the atmospheric layer from the Earth's surface up to an altitude of about 1 kilometer in which wind speed and direction are affected by frictional interaction with objects on the Earth's surface.

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The Pluvio, a weighing rain gauge produced by OTT Hydromet, provides continuous monitoring of liquid, solid, and mixed precipitation accumulation and intensity, taking into account external factors such as temperature and wind. To provide the best possible data load cell and sensor electronics are hermetically sealed against damaging environmental influences with the carrier, bucket and protective housing parts manufactured of high-quality materials. Further information can be found at http://www.ott.com/en-us/products/meteorological-sensors/ott-pluvio2/.

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The Passive Microwave Earth Science Information Partner (PM-ESIP) -- a collaboration of NASA, The University of Alabama in Huntsville (UAH), and Remote Sensing Systems (RSS) -- provides science researchers and users with the capability to interactively customize and receive hydrologic data sets for use in process studies and regional and global climate studies. It provides a framework and a process for creating, supporting, and distributing both producer and customer defined data sets for the broader Earth Observing System (EOS) science community, incorporating emerging technologies such as data content based search (data mining) and data production, gridding, and formatting on demand. PM-ESIP datasets are important for researching long term climate change, seasonal and interannual climate variability, regional assessments, and atmospheric process studies.

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The Particle Measuring System (PMS) Two Dimentional Cloud (2D-C) Probe records the two dimensional shadows of cloud hydrometeors as they pass through a focused Helium-Neon (He-Ne) laser beam in the size range 25-800 micrometers.

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The Particle Measuring System (PMS) Two Dimensional Precipitation (2D-P) Probe records the two dimensional shadows of hydrometeors as they pass through a focused Helium-Neon (He-Ne) laser beam.

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An aircraft mounted Particle Measuring System (PMS) 2D-Stereo probe is a probe that measures radiation and microphysical properties of the cloud layers in two dimensions where laser beams overlap.

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The Precipitation Occurrence Sensor System (POSS) is a bi-static X-band Doppler radar designed by Environment Canada. The POSS measures a signal whose frequency is proportional to the particle Doppler velocity and whose amplitude is proportional to the particle scattering cross-section. Its measurements can be used to provide information regarding precipitation occurrence, type, rate, and rain drop size distribution.

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The Second Generation Precipitation Radar (PR-2) is a dual-frequency, Doppler, dual-polarization radar system that includes digital, real-time pulse compression, extremely compact radio-frequency (RF) electronics, and a large deployable dual-frequency cylindrical parabolic antenna subsystem.

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The total atmospheric water vapor contained in a vertical column of unit cross-sectional area extending between any two specified levels. Usually measured in milligrams per square centimeter.

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Any or all of the forms of water particles, whether liquid or solid, that fall from the atmosphere. Measured in either millimeters per hour or inches per hour.

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The total measured precipitation collected over a specified period of time, usually one day.

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Any or all of the forms of water particles, whether liquid or solid, that fall from the atmosphere. Measured in either millimeters per hour or inches per hour.

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The Precipitation Video Imager (PVI), which is also known as the Snowflake Video Imager (SVI), is a new instrument for characterizing frozen precipitation. A PVI utilizes a video camera with sufficient frame rate, pixels, and shutter speed to record thousands of snowflake images. The camera housing and lighting produce little airflow distortion, so PVI data are quite representative of natural conditions, which is important for volumetric data products such as snowflake size distributions. Long-duration, unattended operation of a PVI is feasible because datalogging software provides data compression, and the hardware can operate for months in harsh winter conditions.

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This is the type of weather observed at the reporting time. These conditions may include types of precipitation like light rain or heavy snow, as well as the condition of the air environment such as foggy, hazy or blowing dust.

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The Model PRT-5 (Precision Raditaion Thermometer) is a battery-powered, infrared radiometer. Extremely versatile, this instrument makes highly sensitive, non-contact temperature measurements in any selected range between -50C and 150C. The PRT-5 can be employed from aircraft, land vehicles, ships or other platforms. It is completely portable, requires no set-up time, and does not depend upon external power. Typical targets for the PRT-5 are sea surface, clouds, sky background, terrain and similar large-area subjects that are difficult or impossible to measure by conventional methods. The PRT-5 consists of a 3.5 pound optical head and a rack-mounted, solid-state electronic control unit. The optical head may be hand-held, by means of a pistol grip attachment, or tripod mounted. It is linked to the electronic control unit by an 8-foot interconnecting cable. When not in use, the optical head is stored in a rugged, protective carrying case, which also contains the control unit and all cables. The standard PRT-5 has a 2-degree field of view, a spectral range of 8 to 14 microns, and a three-range, overlapping temperature scale graduated in degrees C or F. This instrument provides a target spot size of 35 feet at typical working distance of 1,000 feet. With all versions of the PRT-5, measurements are independent of distance as long as the target fills the instrument's field of view. Additional information available at http://www.pyrometer.com/products/prt-5

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The Polarimetric Scanning Radiometer (PSR) is a versatile airborne microwave imaging radiometer developed by the Georgia Institute of Technology and the National Oceanic and Atmospheric Administration (NOAA) Environmental Technology Laboratory for the purpose of obtaining polarimetric microwave emission imagery of the Earth's oceans, land, ice, clouds, and precipitation.

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Pyranometers, often called solarimeters, are a class of actinometers which measure the combined intensity of incoming direct solar radiation and diffuse sky radiation; it consists of a recorder and a radiation sensing element that is mounted so it is able to view the entire sky.

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Any of various devices that measure all the intensity of solar radiation received at the Earth.

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Radar is an acronym for "radio detection and ranging." A radar system usually operates in the ultra-high-frequency (UHF) or microwave part of the radio-frequency (RF) spectrum, and is used to detect the position and/or movement of objects. Radar can track storm systems, because precipitation reflects electromagnetic fields at certain frequencies. Radar can also render precise maps. Radar systems are widely used in air-traffic control, aircraft navigation, and marine navigation.

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The scattering of radiation in a direction opposite to that of the incident radiation due to reflection of the transmitted radar signal back towards the instrument.

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A mapping of the observed radar reflectivity of a scene, consisting of a file of digital numbers assigned to spatial positions on a grid of pixels.

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The measure of the efficiency of a radar target in intercepting and returning radio energy. It depends upon the size, shape, aspect and the dielectric properties of the surface of the target.

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Profiles of the measurement of the efficiency of a radar target in intercepting and returning radio energy. It depends upon the size, shape, aspect and the dielectric properties of the surface of the target.

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The radiant power per unit area per solid angle in a given direction within a given wavelength interval. (watts/m squared - steradian).

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The time rate of change of radio waveforms.

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A radiometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Generally, the term radiometer denotes an infrared radiation detector, yet it also includes detectors operating on any electromagnetic wavelength. A microwave radiometer operates in the microwave wavelengths. The radiometer contains argon gas to enable it to rotate.

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A network of well-distributed radiosonde stations from which variables such as pressure, geopotential height, temperature, dewpoint depression, wind direction and wind speed are obtained.

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A lightweight package of weather instruments fitted with a radio transmitter and carried aloft by a balloon. Radiosondes carry temperature, pressure and relative humidity sensors and report up to six variables: pressure, geopotential height, temperature, dewpoint depression, wind direction and wind speed.

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Precipitation in the form of liquid water droplets greater than 0.5 mm condensed from vapor in the atmosphere. If widely scattered, the drop size may be smaller.

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An instrument that collects and measures the amount of rainfall, expressed in inches or centimeters of depth.

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An instrument that measures and records the level or levels of rain or precipitation.

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A measure of the intensity of rainfall.

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The Regional Air-Sea Interaction (RASI) model uses an event detection algorithm which was developed for identifying and providing statistics on gap wind and ocean upwelling events using Cross-Calibrated, Multi-Platform (CCMP) ocean surface wind and Optimally Interpolated Sea Surface Temperature (OISST) data products.

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Unprocessed data in original packets, as received from the observer.

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A device for upper-air observation that analyzes wind speed and direction, temperature, atmospheric pressure, and relative humidity by means of a balloon-borne adiosonde. A rawinsonde has on board Global Positioning System (GPS), Long Range Navigation (LORAN), or OMEGA navigation to derive windspeeds and directions.

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The NASA Real Time Mission Monitor (RTMM) was a situational awareness tool that integrated satellite, airborne and surface data sets; weather information; model and forecast outputs; and vehicle state data (e.g., aircraft navigation, satellite tracks and instrument field-of-views) for field experiment management. RTMM optimized science and logistic decision-making during field experiments by presenting timely data, graphics and visualizations to the users to improve real time situational awareness of the experiment's assets. The RTMM was proven in the field as it supported program managers, scientists, and aircraft personnel during the 2006 NASA African Monsoon Multidisciplinary Analyses (NAMMA) experiment in Cape Verde, the 2007 Tropical Composition, Cloud and Climate Coupling (TC4) experiment in Costa Rica, the 2007 NOAA-NASA Hurricane Aerosonde Demonstration Project, the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellite (ARCTAS) experiments, the 2008 Soil Moisture Active Passive Validation Experiment (SMAP VEX), 2010, the 2010 Genesis and Rapid Intensification Processes (GRIP) Field Campaign, and 2012-2014 QUASi-Axisymmetric Research (QUASAR) UAV (Unmanned Aerial Vehicle) Experiments.  The integration and delivery of this information was made possible through data acquisition systems, network communication links and network server resources built and managed by collaborators at NASA Dryden Flight Research Center (DFRC) and Marshall Space Flight Center (MSFC).

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A measure of the water-vapor content of air.

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A vessel designed to float on or in the water (including ships, submarines, boats, and barges) used for scientific research.

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The amount of power returned to the radar after its emitted electromagnetic wave is intercepted by a target.

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Radio Frequency Antenna: An instrument receiving directional radiowaves. Can be used to identify cloud-to-ground lightning locations by applying multiple station triangulation on the electromagnetic radiation released by the lightning and detected by the antenna.

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The Rosemount Icing Detector detects supercoiled liquid water content and the onset of airframe icing.

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A device used to directly measure the temperature in a substance, be it soil, water or air. Temperature probes are used on aircraft to measure outside air temperature; often in conjunction with other sensors as in Bowen ratio apparatus; or used to determine water temperature.

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Electric field mills are used to measure the vertical component of the electric field as the aircraft flies in the vicinity of electrified clouds. The dynamic range of these instruments extends from the fair weather fields (a few tens of volts per meter (V/m)) to large thunderstorm fields (thousands of V/m). Using these field mills, it is possible to detect both intracloud and cloud-to-ground lightning from the abrupt electric field changes in the data.

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Remote Sensing Systems.

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Tropical cyclones have significantly altered normal coastal processes and characteristics in the Gulf region through sediment disturbance. The Sediment Analysis Network for Decision Support (SANDS) project addresses sediment redistribution issues by producing a suite of decision support products, derived from satellite observations from the Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) instruments, for assessment and monitoring of suspended sediment and sediment deposition in the north central Gulf of Mexico region. These products support resource management, planning, and decision making activities in the Gulf of Mexico. The project also facilitates delivery of the resulting products to end users by making them available through a SANDS portal hosted at the Geological Survey of Alabama (GSA) and through NASA's Global Hydrometeorology Resource Center.

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A man-made vehicle orbiting the earth or other celestial body

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The Scanning Raman Lidar (Light Detection and Ranging) is an instrument designed to determine the composition and vertical distribution of several atmospheric constituents, specifically water vapor and aerosols. The SRL was located on Andros Island during the Third Convection And Moisture EXperiment (CAMEX-3) campaign, and operated nearly every night (exceptions noted) throughout the period August 6 through September 20, 1998.

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The interaction between radiation in the atmosphere and air molecules or suspended particles, resulting in the diffusion of the radiation in all directions but involving no loss of radiant energy.

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The ratio of the area of the water surface covered by ice as a fraction of the whole area. Sea ice concentration has been monitored by polar orbiting satellites at all wavelengths.

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A measure of the thermal energy at or near the air/water interface of the sea or ocean. The depth of the surface layer depends on the method of measurement. Units are typically in degrees Fahrenheit (F) or Celsius (C) or in Kelvins (K).

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An index that represents sea surface temperature (SST).

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Variations in magnetic fields are measured along three orthogonal components with respect to the aircraft.

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The SeaWinds scatterometer is a specialized microwave radar that measures near-surface wind velocity (both speed and direction) under all weather and cloud conditions over Earth's oceans. The experiment is a follow-on mission and continues the data series initiated in 1996 by the NASA scatterometer (NSCAT). The SeaWinds instrument was launched on the NASA Quick Scatterometer (QuikScat) "quick recovery" satellite on June 19, 1999. SeaWinds was also launched on the Japan Aerospace Exploration Agency (JAXA) Advanced Earth Observation Satellite II (ADEOS-II) on December 14, 2002. ADEOS-II failed on October 24, 2003. SeaWinds uses a rotating dish antenna with two spot beams that sweep in a circular pattern. The antenna radiates microwave pulses at a frequency of 13.4 gigahertz across broad regions on Earth's surface. The instrument will collect data over ocean, land, and ice in a continuous, 1,800-kilometer-wide band, making approximately 400,000 measurements and covering 90 percent of Earth's surface in one day.

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Sediment transport is the movement of solid particles (sediment), typically due to a combination of the force of gravity acting on the sediment, and/or the movement of the fluid in which the sediment is entrained.

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Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained, and come to rest against a barrier.

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Sediment is naturally-occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself; an accumulation of rock and minerals carried by water.

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Raw sensor and calibration satellite data that can be processed into Antenna Temperatures.

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The Spinning Enhanced Visible and InfraRed Imager (SEVIRI) has the capacity to observe the Earth in 12 spectral channels and provide image data which is core to operational forecasting needs.

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The sferics detector detects the impulsive radio noise emitted by a lightning strike in the Very Low Frequency (VLF) spectrum between 7 and 15 kHz. In the VLF portion of the radio spectrum sferics propagate thousands of kilometers through the earth-ionosphere waveguide.

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A large seagoing vessel propelled by power or sail

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The loss or movement of land along the coastline, due to a variety of impacts such as waves, tides, current, etc.

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The radiant energy emitted from the sun, in the visible and near ultraviolet wavelengths of the electromagnetic spectrum.

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Skin temperature refers to the effective radiating temperature of the soil plus canopy surface. It is inferred from satellites in the 8-12 um window region. In climate models, it is the temperature used to determine upward thermal emission. The skin temperature usually shows a larger diurnal variation than the surface air temperature, a factor that needs to be considered when evaluating data/model comparisons. See [R. E. Dickinson. Land surface. In K. E. Trenberth, editor, Climate System Modeling, pages 149-171. Cambridge Univ. Press, 1992].

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A "Slow" and "Fast" antennas system acquires lightning waveforms and provides a measure of total lightning. The system consists of a flat plate antenna anda broadband charge amplifier with a selectable time constant (i.e., "slow antenna" or "fast antenna"), a filter for removing undesired signals (e.g., radio frequency interference), a transient waveform recorder, and a data acquisition system.

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The Shared Mobile Atmospheric Research and Teaching Radar (SMART-R) is a portable 5 cm Doppler radar. All equipment- antenna, power generator, processors and readout computers are truck mounted to provide maximum transportability.

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The Surface-sensing Measurements for Atmospheric Radiative Transfer - Chemical, Optical, and Microphysical Measurements of In-situ Troposphere (SMART-COMMIT) system consists of a suite of insitu and remote sensing instruments that measures parameters which characterize constituents of the atmosphere at a given location. Some of the included instrumentation are the Atmospheric Emitted Radiance Interferometer (AERI), a micropulse lidar, radiosonde, microwave radiometer, nephlometers and total sky imager.

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Scanning Multichannel Microwave Radiometer: a ten channel passive microwave instrument using six conventional Dicke-type radiometers. It delivered orthogonally polarized antenna temperature data at five frequencies (6.6, 10.69, 18.0, 21.0, and 37.0 GHz).

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Marshall Space Flight Center internal inventory table used for cataloging metadata

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A type of frozen precipitation composed of white or translucent ice crystals, chiefly in complex branch hexagonal form and often agglomerated into snow-flakes, especially at temperatures warmer than -5C (23F).

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Snow density is defined as mass per unit volume; i.e., it's the mass of a given amount of substance divided by the volume occupied by that amount.

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Pertaining to the thickness of snow pack throughout the year.

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A snow tube also known as a snow sampler is a hollow tube for collecting a sample of snow in situ.

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Pertaining to the measurement of the amount of water in a given snow pack.

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The Doppler sodar (sonic detection and ranging) operates near 2000 Hz frequency (tunable between 1800-2200 Hz) and measures wind components along three beams, including a vertical beam. The backscattered power is proportional to the temperature structure function (or coefficient), CT2, and provides information on Atmospheric Boundary Layer (ABL) stability and turbulence characteristics. Returned values include horizontal winds, vertical velocity, and virtual temperature profiles when in Radio Acoustic Sounding System or RASS mode.

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The water lost from soil upon drying to constant mass at 105 degrees Celcius; expressed either as the mass of water per unit mass of drysoil or as the volume of water per unit bulk volume of soil.

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A device that measures the total amount of water, including the water vapor, in unsaturated soil.

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The water lost from soil upon drying to constant mass at 105 degrees Celcius; expressed either as the mass of water per unit mass of drysoil or as the volume of water per unit bulk volume of soil.

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The degree of hotness or coldness of the soil as measured on some definite temperature scale.

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The total solar radiant energy flowing across a unit area normal to the direction of propagation and located at the mean distance of the Earth from the Sun.

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A measure of the electromagnetic energy that comes from the sun only.

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The difference between propagation constants for horizontally- and vertically- polarized radar pulses over a given range.

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Measure of velocity dispersion within the radar sample volume.

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Any of various optical instruments, for measuring wave length, index of refraction, etc.

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The width of the Doppler power spectrum.

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Special Sensor Microwave/Imager: a passive microwave radiometric system that receives both horizontally and vertically linearly polarized radiation at 19.3,37.0, and 85.5 GHz and vertical only at 22.2 GHz.

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The Special Sensor Microwave Atmospheric Temperature Sounder consists of seven microwave channels with atmospheric sensitivity in the oxygen absorption band, at frequencies ranging from 50.5 to 59.4 GHz, with one channel acting as a surface window channel.

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The Special Sensor Microwave Water Vapor Sounder is a scanning, five channel, passive and total power microwave radiometer system consisting of five channels: three water vapor channels centered around the 183.31 GHz water vapor line, a 91 GHz channel, a 150 GHz channel.

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Special Sensor Microwave/Imager: a passive microwave radiometric system that receives both horizontally and vertically linearly polarized radiation at 19.3,37.0, and 85.5 GHz and vertical only at 22.2 GHz.

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Special Sensor Microwave Imager (SSM/I) Inventory (INV): Marshall Space Flight Center internal inventory table used for cataloging metadata

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The Special Sensor Microwave Imager/Sounder (SSMI/S) combines the channel frequencies of the Special Sensor Microwave Atmospheric Temperature Sounder (SSMT), SSMT/2, and Special Sensor Microwave/Imager (SSM/I) into a single sensor. It measures the thermally emitted radiation from the Earth at 24 channels from 19 to 183 GHz. The SSMI/S was initially launched aboard the Defence Meteorological Satellite Program (DMSP) F-16 satellite on October 18, 2003. Presently it is aboard the F16, F17 and F18 DMSP satellites and is planned for F19 and F20.

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The pressure of undisturbed (static) air

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The temperature of undisturbed (static) air.

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The rate of water flowing in a channel, usually measured in cubic feet per second.

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A device for measuring the elevation of the water surface in a stream.

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The rate of water flowing in a channel, usually measured in cubic feet per second.

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A data collection site for streamflow discharge, where streamflow is defined as the rate of water flowing in a channel, usually measured in cubic feet per second.

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The land or oceanic interface with the atmosphere

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The Surface Acoustic Wave (SAW) device is a quartz crystal designed to support high-frequency acoustic oscillations. Because these oscillations are quite sensitive to surface effects, condensation produces a measurable shift in the resonance frequency of the SAW device. A two-stage thermo-electric cooler electronically heats or cools the SAW device maintaining it at the dewpoint, while a platinum resistor is used to monitor the dewpoint temperature.

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The temperature of the air near the surface of the earth.

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The amount of water vapor in the air near the surface of the earth.

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The wind measured at a surface observing station or recorded at an observing site at the ocean surface.

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The atmospheric pressure at a given location on the surface of the Earth.

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The speed and direction of wind (measured directly or calculated from remotely sensed data) near the earth's land (or water) surface. Usually varies from 2 to 10 meters above the surface.

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The speed and direction of wind (measured directly or calculated from remotely sensed data) near the earth's land (or water) surface. Usually varies from 2 to 10 meters above the surface.

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To Be Determined

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The NASA TC4 (Tropical Composition, Cloud and Climate Coupling) mission investigated the atmospheric structure, properties and processes in the tropical Eastern Pacific. The primary area of interest was the atmosphere layer between approximately 46,000 ft and 59,000 ft (14-18 km). This is where the lower part of the atmosphere (the troposphere) meets the upper part (the stratosphere). The TC4 mission was sponsored by the NASA Headquarters Atmospheric Composition Focus Area, including the Upper Atmospheric Research Program, the Radiation Science Program, and the Tropospheric Chemistry Program. The field experiment phase was completed during July and August 2007 based out of San Jose, Costa Rica.

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The Tropical Cloud Systems and Processes (TCSP) mission was a field research investigation sponsored by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). TCSP focused on the study of the dynamics and thermodynamics of precipitating cloud systems, including tropical cyclones using NASA-funded aircraft and surface remote sensing instrumentation.TCSP took place during July 2005 out of the Juan Santamaria Airfield in San Jose, Costa Rica.

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The TExas and FLorida UNderflights (TEFLUN) Experiment was a mission to obtain validation measurements for the Tropical Rain Measuring Mission (TRMM). TRMM is a NASA and National Space Development Agency of Japan (NASDA) coordinated mission that launched the TRMM satellite on 28 November 1997 with a unique complement of sensors to remotely observe rainfall throughout the global tropics. TEFLUN was the first in a series of experiments using a combination of airborne and surface-based measurements to complement the satellite data. Among these, were important measurements aboard the NASA high-altitude aircraft, similar to those on the TRMM satellite. They are used for direct intercomparisons with TRMM overflights where possible, but more frequently to simulate TRMM data by flying over precipitation systems within the experimental domain. These, along with surface-based measurements and computer models, made unique contributions to our understanding of the tropical precipitation cycle.

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The Texas Florida Underflight Experiment (TEFLUN) is a series of field research investigations sponsored by the Earth Science Enterprise of the National Aeronautics and Space Administration (NASA). TEFLUN-B took place in conjunction with CAMEX-3, and collected data from 8 August through 23 September, 1998, to study tropical convective precipitation using NASA-funded aircraft and surface remote sensing instrumentation.

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Average kinetic energy of a substance measured in degrees.

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The term 'temperature anomaly' means a departure from a reference value or long-term average. A positive anomaly indicates that the observed temperature was warmer than the reference value, while a negative anomaly indicates that the observed temperature was cooler than the reference value.

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A device used to directly measure the temperature in a substance, such as soil, water, or air. Temperature probes are used on aircraft to measure outside air temperature; often in conjunction with other sensors as in the Bowen ratio apparatus; or used to determine water temperature.

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A record of temperature versus height at a specific geographic location.

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A meteorological sensor used to measure temperature.

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Terra, formerly known as Earth Observing Satellite (EOS) AM-1 (AM: crosses the equator in the morning), launched 18 December 1999, is the flagship of the NASA Earth Science Enterprise (ESE). It observes and measures the state of the Earth system, while also monitoring global environmental changes over time. TERRA carries 5 state-of-the-art instruments uniquely designed to provide data with unprecendented precision, quality, and scope. These data are processed into continuous long-term measures of the state of the atmosphere, land, and oceans. The 5 instruments include the 1) Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), obtaining high-resolution images at 14 wavelengths (visual (VIS) and infrared (IR)), 2) Clouds and the Earth's Radiant Energy System (CERES), measuring the radiation budget and providing cloud property estimates, 3) Multi-angle Imaging Spectro-Radiometer (MISR), containing 9 cameras imaging at 4 wavelengths (VIS and IR), 4) Moderate-resolution Imaging Spectroradiometer (MODIS), observing in 36 spectral bands, and 5) Measurements of Pollution in the Troposphere (MOPITT), observing in 3 spectral bands using gas correlation spectroscopy.

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A sensor aboard Landsat 4-5 which acquires images of the earth from 7 spectral bands for earth reflectance data and earth temperature data. The spatial resolution of bands in the visible and reflective infrared regions is 30 meters. Currently, the TM sensor on Landsat 5 is still collecting data.

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A resistive circuit component which has a high negative temperature coefficient of resistance, so that its resistance decreases as the temperature increases. It is a stable, compact, rugged two-terminal ceramic like semiconductor head, rod,or disk. Derived from thermal resistance.

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Temperature probes provide ground surface temperature measurements and can be submerged in water and/or buried in soil.

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An instrument for measuring temperature.

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The Television Infrared Observation Satellite (Tiros)-N was part of the ongoing US series of polar-orbiing weather satellites. These satellites made measurements of atmospheric temperature and humidity, suface temperature, cloud cover, water-ice-moisture boundaries, and space proton and electron fluxes. They could receive, process, and retransmit data from free-floating ballons, buoys, and remote automatic stations around the globe. These were managed by the National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) was responsible for developing and launching the spacecraft.

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The TRMM Microwave Imager (TMI) is a 5-channel, dual-polarized, passive microwave radiometer. Microwave radiation is emitted by the Earth's surface and by water droplets within clouds. The TMI is used to measure several important meterological parameter over sea surfaces. The TMI, a successor to the Special Sensor Microwave/Imager (SSM/I), measures radiation at frequencies of 10.7, 19.4, 21.3 85.5 GHz. It orbits at an altitude of 218 miles, much lower than the SSM/I, thus providing better resolution.

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Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment - a large scale field observation campaign (11/92 to 2/93) conducted over the western Pacific warm pool.

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Doppler scanning radar operating in the C-band with horizontal and vertical polarization. Used for detection and detailing wind direction/velocities in the x, y and z direction as well as precipitation reflectivities.

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The HotPlate provides a measure of the liquid precipitation rate and accumulation for snow. It consists of two parallel, heated metal disks each insulated from one another, and its measurement principle is based on the amount of cooling produced by melting and evaporation of precipitation as it impacts the upward facing disk. The temperatures of the heated disks are such that the measurements become available immediately after the precipitation impacts the disk. One advantage of this instrument is its small form factor which greatly reduces the impacts the instrument may produce on the surrounding wind field and thereby reduces the possibility of under-sampling precipitation particles (i.e., under catch). The HotPlate was designed by scientists at the National Center for Atmospheric Research and manufactured by Yankee Environmental Systems (Rasmussen et al. 2011).

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Measurement made in a pitot-static system which is the sum of ram air pressure plus the ambient pressure of the air entering the pitot tube.

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Total Sky Imager by the Yankee Environmental Systems is a full color sky camera and software package for sky imaging, recording up to 6 images per minute. A nephelometer and an aerodynamic particle sizer are also incorporated for measuring the aerosol particles and light scattering.

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Measurement made using a temperature probe (e.g. thermistor) which is the sum of the ambient air temperature plus the heat of friction caused by the high speed air passing over the probe.

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The total atmospheric water vapor contained in a vertical column of unit cross-sectional area extending between any two specified levels, commonly expressed in terms of the height to which that water substance would stand if completely condensed and collected in a vessel of the same unit cross section.

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Television Infrared Observation Satellite (TIROS) Operational Vertical Sounder. The TOVS instrumentation on-board the National Oceanic and Atmospheric Administration (NOAA) satellites consist of three parts: 1) the second version of the High-resolution Infrared Radiation Sounder (HIRS-2), 2) the Microwave Sounding Unit (MSU), and 3) the Stratospheric Sounding Unit (SSU).

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Concentration of gases in the atmosphere that do not occur in large quantities but are significant to life on Earth or are important constituents of the chemical cycles in the atmosphere.

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Concentration of gases/species in the atmosphere that do not occur in large quantities but are significant to life on Earth or are important constituents of the chemical cycles in the atmosphere.

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The Tretyakov non-recording precipitation gauge has been used historically as the official precipitation measurement instrument in the Russian (formerly the USSR) climatic and hydrological station network and in a number of other European countries. From 1986 to 1993, the accuracy and performance of this gauge were evaluated during the World Meteorological Organization (WMO) Solid Precipitation Measurement Intercomparison at 11 stations in Canada, the USA, Russia, Germany, Finland, Romania and Croatia. The double fence intercomparison reference (DFIR) was the reference standard used at all the Intercomparison stations in the Intercomparison. The Intercomparison data collected at the different sites are compatible with respect to the catch ratio (measured/DFIR) for the same gauge, when compared using mean wind speed at the height of the gauge orifice during the observation period. http://onlinelibrary.wiley.com/doi/10.1002/hyp.3360090805/abstract

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The Tropical Rainfall Measuring Mission (TRMM) is a joint mission between NASA and the National Space Development Agency (NASDA) of Japan designed to monitor and study tropical rainfall and the associated release of energy that helps to power the global atmospheric circulation shaping both weather and climate around the globe. The TRMM Observatory carries five instruments: the first spaceborne Precipitation Radar (PR), the TRMM Microwave Imager (TMI), a Visible and Infrared Scanner (VIRS), a Cloud and Earth Radiant Energy System (CERES), and a Lightning Imaging Sensor (LIS).

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The Tropical Rainfall Measuring Mission Large-scale Biosphere-Atmosphere Experiment (TRMM-LBA) was conducted on an ER-2 (Earth Resources 2) aircraft flying over the Amazon River basin. The Advanced Microwave Precipitation Radiometer (AMPR), ER-2 Lightning Instrument Package (LIP) and several other instruments were aboard the aircraft. This allowed direct comparison over a large land area of in situ ground based radars and rain gauge networks, to the TRMM instruments and the ER-2 instrumentation.

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Atmospheric temperature extending from the earth's surface to the tropopause

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The irregular and instantaneous motions of a liquid or gas which is made up of a number of small eddies that travel in the general flow direction.

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The Tropical Warm Pool International Cloud Experiment (TWPICE) was conducted in the area around Darwin, Australia, in early 2006. The aim of the experiment was to examine convective cloud systems from their initial stages through to the decaying and thin high level cirrus and measure their impact on the environment.

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The University of Alabama in Huntsville

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An Ultra High Sensitivity Aerosol Spectrometer (UHSAS) is an optical-scattering, laser-based aerosol particle spectrometer system for sizing particles in the 0.06 - 1 micrometer range.

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Electromagnetic radiation of shorter wavelength than visible radiation but longer than x-rays. Wavelengths range from 5 - 400mm.

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The UND Cessna Citation II Research Aircraft used for MC3E is owned and operated by the University of North Dakota. The Citation II is a twin-engine fanjet with an operating ceiling of 43,000 feet (13.1 km). The turbofan engines provide sufficient power to cruise at speeds of up to 340 knots (175 m s-1) or climb at 3300 feet per minute (16.8 m s- 1). These high performance capabilities are accompanied by relatively low fuel consumption at all altitudes, giving the Citation an on-station time of 3-5 hours, depending on mission type. Long wings allow it to be operated out of relatively short airstrips and to be flown at the slower speeds (140 kts/72 m s-1) necessary for many types of measurements. The Citation is certified for flight into known icing conditions.

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UNESCO, the United Nations Educational, Scientific, and Cultural Organization, is a Specialized Agency of the United Nations. The main objective of UNESCO is to contribute to peace and security in the world by promoting collaboration among nations through education, science, culture and communication in order to further universal respect for justice, for the rule of law and for the human rights and fundamental freedoms which are affirmed for the peoples of the world, without distinction of race, sex, language or religion, by the Charter of the United Nations.

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The temperature of the atmosphere well above Earth's surface.

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Atmospheric winds above the surface measured by either radiosonde (weather balloon) or aircraft, or derived from satellite imagery.

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Atmospheric temperature measured in degrees Kelvin extending from 500 to 100 hPa (Hectopascals).

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The mass of water per unit mass of biomass.

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This vertically pointing radar operating at 2.8 GHz (S-band) measures the backscattered power from raindrops and ice particles as precipitating cloud systems pass overhead. After calibration, the instrument provides an unattenuated reflectivity estimate through the precipitation.

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The component of the wind velocity vector rising perpendicular to the plane of the horizon.

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A graph of the value of a scalar quantity (e.g. direction and/or speed) versus a horizontal, vertical or timescale of wind.

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The VertiX is a vertical pointing X-band radar which can detect all precipitation targets, some ice clouds and the turbulence associated with developing cumulus clouds (barely). It is also capable of measuring the Doppler velocity of targets.

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Device used to capture moving images that can then be replayed on a monitor.

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The greatest distance at which a black object of suitable dimensions, situated near the ground, can be seen and recognized when observed against a bright background.

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The product of an imager observing in the visible portion of the spectrum. These are the most familiar of the meteorological satellite products, and are often displayed during the evening news and erroneously called 'satellite pictures'.

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Upwelling radiation in the visible portion of the spectrum which is observed by the spacecraft instrumentation.

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Visible Infrared Spin Scan Radiometer (VISSR) is a two channel instrument observing in the infrared and visible portion of the electromagnetic spectrum that provides day/night observations of cloud cover and earth/cloud radiance temperatures over a partial or full earth disk for use in operational weather analysis and forecasting.

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The act of making and recording a measurement by visually looking at it with the eyes.

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The W-Band radar is a single antenna, pulsed, vertical pointing Doppler radar system with range of 75 to 110 GHz.

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The Water Content Reflectometer measures the volumetric water content of porous media using time-domain measurement methods. The reflectometer connects directly to the single-ended analog input of a datalogger. The datalogger period or frequency output can be converted to volumetric water content using calibration values.

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Gassious form of water.

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The Nevzorov (a type of water vapor probe) probe is a so-called hot-wire device. Two resistors are heated to evaporate all particles that touch their surface during the flight. Due to their shape they are able to catch small droplets or droplets and ice crystals. The amount of energy necessary to evaporate particles is a direct measure of the liquid water content (rectangular sensor) and the total water content (cone), respectively.

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A profile is defined as a graph of the value of a scalar quantity versus a horizontal, vertical, or time scale. It usually refers to a vertical representation.

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The rate of change in water wapor over a specified period (e.g., 3 hours).

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Parameters such as main channel slope, stream length, basin elevation, surface storage area of lakes, percent of contributing drainage area of ponds, swamps, and lakes, and mean annual precipitation used in water resource studies.

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The U.S. Geological Survey (USGS) National Water Storage and Retrieval System: an extensive database of surface-water data, including streamflow information and watershed characteristics.

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The Wyoming Cloud Radar (WCR) is a 95Ghz, dual-channel, Doppler Radar designed for airborne use. The University of Wyoming (UW) King Air installation of the WCR uses three antennas: one that can look either upward or horizontally (to the right of the aircraft) plus two downward-looking antennas (one at nadir; the second slanted ~30 degrees forward of nadir along the aircraft centerline).

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A non-permeable, inflatable membrane made of a light material, filled with a gas lighter than air, designed to rise or float in the atmosphere.

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Weather Stations are facilities or locations where meteorological data are gathered, recorded, and released. Such stations are of the first order when they make observations of all the important elements either hourly or by self-registering instruments; of the second order when only important observations are taken; of the third order when simpler work is done, as to record rainfall and maximum and minimum temperatures.

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Identification of lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water.

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The Coordinated Management And Networking Of Mediterranean Wetlands (WetNet) project is a passive microwave research project using the Special Sensor Microwave/Imager (SSM/I) instrument which investigated the feasibility of conducting scientific research with a network connected distributed database. The WETNET project took place for several years beginning in 1990.

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Wind Monitor or Propeller Wind Monitor is "a light-weight, sturdy instrument for measuring wind speed and direction in harsh environments. Its simplicity and corrosion-resistant construction make it ideal for a wide range of wind measuring applications." [Source Text (in quotes above) is from Campbell Scientific home page, http://www.campbellsci.com/05103-l]

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The term applied to Doppler radars operating in the Very High Frequency - Ultra High Frequency (VHF-UHF) band (30MHz-3GHz) that determine the wind by measuring the line-of-sight doppler shift of scattered signals from refractive index fluctations caused by turbulence.

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A graph of the value of a scalar quantity (e.g.,direction and/or speed) versus a horizontal, vertical or timescale of wind.

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The distance a parcel of air travels per unit time at constant pressure is the speed, and the true direction in degrees measured from north from which it travels is the direction.

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The distance a parcel of air travels per unit time at constant pressure is the speed, and the true direction in degrees measured from north from which it travels is the direction.

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WindSat is a joint NOAA (National Oceanic and Atmospheric Administration) Integrated Program Office/Department of Defense/NASA demonstration project, intended to measure ocean surface wind speed and wind direction from space using a polarimetric radiometer. It was launched aboard the Coriolis satellite by a Titan II rocket on 6 January 2003 into a 830-km 98.7-degree orbit, and is designed for a three-year lifetime.

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The Weather Surveillance Doppler Radar (WSR)-57S was an S-band weather radar which was operated by the National Weather Service (NWS) starting in 1957. No WSR-57S radars are currently operational with the NWS.

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The Weather Surveillance Doppler Radar (WSR)-74C was a C-band weather radar which was operated by the National Weather Service (NWS) starting in 1974, ending in 1997.

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The Weather Surveillance Doppler Radar (WSR)-88D is an S-band Doppler weather radar currently operated by the National Weather Service (NWS).

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Aircraft from the University of Wyoming.

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The X-band Polarimetric On Wheels (X-POW) is a Doppler scanning radar operating in the X-band at -9.3 GHz with horizontal and vertical polarization. Used for detection and detailing surface rainfall rate and precipitation classification fields, 3D precipitation microphysical retrievals including water/frozen hydrometeor contents and drop size distribution profiles.

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Data values assigned to a grid regularly spaced in .5 degrees latitude by .5 degrees longitude

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File contains granules for one day

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Reconstructed, unprocessed instrument data at full resolution and time referenced

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Radiometrically corrected/calibrated data in physical units, full resolution

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Derived geophysical parameters at the same resolution and location as the Level 1 data

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Data values assigned to a grid regularly spaced in 2.5 degrees latitude by 2.5 degrees longitude

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The two dimensional cloud probe 2D-C is a particle spectrometer which measures the size and shape of cloud particles from 75 micrometers to 1900 micrometers, using a 32-element linear diode array at an image resolution of 30 micrometers per pixel. Particle size distributions, derived parameters, and particle images are available from this instrument.

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The Two-dimensional Video Disdrometer (2DVD) uses two high speed line scan cameras which provide continuous measurements of size distribution, shape and fall velocities of all precipitation particles and types. This 2DVD is the third generation 2D video disdrometer designed by Joanneum Research of Graz, Austria.

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Retrieved environmental variables, spatially/temporarily resampled

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Data values assigned to a grid regularly spaced in 4 degrees latitude by 5 degrees longitude

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The mean of the data values over a 5 day period

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Data values assigned to a grid regularly spaced in 5.0 degrees latitude by 5.0 degrees longitude

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Storage medium for inventory data

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Storage medium for inventory data

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