GRIP GOES Images
Table of Contents
Introduction
GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. They circle the Earth in a geosynchronous orbit, which means they orbit the equatorial plane of the Earth at a speed matching the Earth's rotation. This allows them to hover continuously over one position on the surface. The geosynchronous plane is about 35,800 km (22,300 miles) above the Earth, high enough to allow the satellites a full-disc view of the Earth. Because they stay above a fixed spot on the surface, they provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms, and hurricanes. When these conditions develop the GOES satellites are able to monitor storm development and track their movements.
These GOES imagery files were produced and archived in near real time here at the Global Hydrology and Climate Center (http://ghcc.nsstc.nasa.gov) throughout the Genesis and Rapid Intensification Processes (GRIP) campaign. These image files were created for use with the Real Time Mission Monitor (RTMM). Generally, GOES-11 and GOES-13 images are available for all dates between August 15 and September 30, 2010 at 15 minute intervals throughout this time period.
Three channels of images were produced and archived:
channel 1 - visible (0.55-0.75 microns)
channel 3 - moisture infrared (6.5-7 microns)
channel 4 - thermal infrared (10.2-11.2 microns)
The spatial resolution for visible imagery is 1 km. at nadir and the infrared imagery resolution is 4 km. Additional information about the GRIP field experiment can be found at the official GRIP web site: http://grip.nsstc.nasa.gov/
Instrument Description
The GOES I-M 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.
File Naming Convention
These GOES browse images are similarly named and maintained. The filename format for these appears as:
YYYY-MM-DD_hh-mm-ss_GE_GOES-NN_<channel>_<type>.png
where,
YYYY = four digit year
MM = month
DD = day
hh = hour
mm = minute
ss = seconds
NN = satellite number (11 or 13)
channel = (IR3, IR4, VIS)
type = (GRIP, CONUS, GULF)
png = Portable Network Graphics
Image Format
These images products were produced in PNG (Portable Network Graphics), an open bitmap Extensible image file format with lossless Compression.
NOTE: These images were created near real time during the GRIP mission from non-quality controlled GOES raw data. There are known gaps in these images, where raw data was not available. Better quality images could be generated by requesting the GOES raw data from CLASS and reprocessing. Our image holdings here at the GHRC will remain "quicklook" quality only.
References
Additional information about the GRIP field experiment, and the NOAA satellites can be found at these sites:
Ordering Data
The Global Hydrology Resource Center (GHRC) User Services Office staff is the point of contact for all questions, comments, and inquiries about these images, and all other GHRC services. You can order data directly through our data ordering system (HyDRO).
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/
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