GPM Ground Validation DC-8 Navigation and Housekeeping Data GCPEx
Table of Contents
Introduction
During the GPM Cold-season Precipitation Experiment (GCPEx), NASA'S DC-8 aircraft served as a high altitude GPM core satellite instrument simulator. The DC-8 carried the Conical Scanning Millimeter-wave Imaging Radiometer (CoSMIR) and the Second-Generation Airborne Precipitation Radar (APR-2) instruments in order to simulate the GPM core satellite.
The GPM Ground Validation DC-8 Navigation and Housekeeping data set is composed of two types of files. National Suborbital Education and Research Center (NSERC) of the University of North Dakota (UND) provided the geo-located housekeeping data which includes altitude, pressure, air speed, wind speed and other attributes. The NASA DC-8 Navigation data, in comma delimited IWG1 format, was collected and utilized in-flight by the Real-Time Mission Monitor. Both file types are available for most of the data set dates, however please note that there are a few dates where only the IWG1 formatted data is available.
Campaign
The GPM Cold-season Precipitation Experiment (GCPEx) occurred in Ontario, Canada during the winter season of 2011-2012. GCPEx addressed shortcomings in the GPM snowfall retrieval algorithm by collecting microphysical properties, associated remote sensing observations, and coordinated model simulations of precipitating snow. These data sets were collected to aid in the achievement of the over arching goal of GCPEx which is to characterize the ability of multi-frequency active and passive microwave sensors to detect and estimate falling snow.
Further details on GCPEx are available at http://gpm.nsstc.nasa.gov/gcpex. Information on the Global Precipitation Measurement (GPM) mission is available at http://pmm.nasa.gov/GPM.
Instrument Description
NASA operates the DC-8 aircraft as an airborne science laboratory. The DC-8 is used to collect data in support of projects serving the world's scientific community. The DC-8 is equipped with the NASA Real Time Mission Monitor (RTMM) data server. RTMM is a situational awareness tool that integrates satellite, airborne, and surface data sets for field experiment management. Data and imagery is transmitted between the DC-8 and the ground using the Research Environment for Vehicle-Embedded Analysis on Linux (REVEAL) communications system. The DC-8 REVEAL transfer of data allows easy access to aircraft data by experimenter-operated computers. Further details on the RTMM are available at http://rtmm.nsstc.nasa.gov/index.html.
Investigators
Richard Blakeslee
NASA Marshall Space Flight Center
Huntsville, AL
35805
David Van Gilst
NSERC Network Engineer
National Suborbital Education and Research Center
University of North Dakota
File Naming Convention
The GPM Ground Validation DC-8 Navigation and Housekeeping data set is composed of two types of ASCII files. The navigation files were obtained during the GCPEx mission and were managed by the Real-Time Mission Monitor (RTMM). These files are named with the following convention:
GCPEX_nav_[YYYY-MM-DD]_DC8.dat
where,
GCPEX = GPM Cold-season Precipitation Experiment
nav = navigation
YYYY = year
MM = month
DD = day
dat =
IWG1 text file extension
The housekeeping files were provided by NSERC from the University of North Dakota(UND) and are named with the following convention:
GCPEX_nav_dc8_[YYYYMMDD]_r1.ict
where,
GCPEX = GPM Cold-season Precipitation Experiment
nav_dc8 = description of the platform used (DC-8 aircraft)
YYYY = year
MM = month
DD = day
r1 = the revision number of the data
ict = file extension for the ICARTT data format
The UND files are daily files with the exception of one day (February 12, 2012) which has two files. These files are named as follows:
GCPEX_nav_dc8_20120212_1_r1.ict
GCPEX_nav_dc8_20120212_2_r1.ict
*Note: There are a few dates where only the IWG1 formatted data is available.
A PDF document is also included in the data files and is named with the following convention:
GCPEx_Flight-Time_Details-cit.pdf
The PDF document outlines the flight date, flight start and stop times, and the type of precipitation event observed.
Data Format
The housekeeping data from the University of North Dakota consists of ASCII (.ict) files. The .ict files are structured in the ICARTT data format. Additional details on the ICARTT data format can be found at http://ghrc.nsstc.nasa.gov/uso/ds_docs/doc_common/ESDS-RFC-019-v1.1_0-ICARTT.pdf.
The navigation data from the RTMM consists of IWG1 ASCII (.dat) files. The document ftp://gpm.nsstc.nasa.gov/gpm_validation/gcpex/nav_dc8/doc/icats_format_readme.txt provides further details on the data obtained from the RTMM.
Citation
Our data sets are provided through the NASA Earth Science Data and Information System (ESDIS) Project and the Global Hydrology Resource Center (GHRC) Distributed Active Archive Center (DAAC). GHRC DAAC is one of NASA's Earth Observing System Data and Information System (EOSDIS) data centers that are part of the ESDIS project. ESDIS data are not copyrighted; however, in the event that you publish our data or results derived by using our data, we request that you include an acknowledgment within the text of the article and a citation on your reference list. Examples for general acknowledgments, data set citation in a reference listing, and crediting online web images and information can be found at: http://ghrc.nsstc.nasa.gov/uso/citation.html
Contact Information
To order these data or for further information, please contact:
Global Hydrology Resource Center
User Services
320 Sparkman Drive
Huntsville, AL 35805
Phone: 256-961-7932
E-mail: support-ghrc@earthdata.nasa.gov
Web: http://ghrc.nsstc.nasa.gov/
|