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GRIP Meteosat Second Generation (MSG) Image Data Table of Contents
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. Each Meteosat satellite is expected to remain in orbit in an operable condition for at least seven years. The current policy is to keep two operable satellites in orbit and to launch a new satellite close to the date at which the elder of the two comes to the end of its on-board fuel. The Genesis and Rapid Intensification Processes (GRIP) experiment was a NASA Earth science field experiment conducted August 5 to September 30, 2010. The major goal was to better understand how tropical storms form and develop into major hurricanes. NASA used the DC-8 aircraft, the WB-57 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 capitalized on a number of ground networks and space-based assets, in addition to the instruments deployed on aircraft from Ft. Lauderdale, Florida ( DC-8), Houston, Texas (WB-57), and NASA Dryden Flight Research Center, California (Global Hawk). More information about this Campaign can be found on the GRIP web site: https://ghrc.nsstc.nasa.gov/home/field-campaigns/grip. Like the previous generation of Meteosat satellites, MSG is spin-stabilised. When operating in geostationary orbit, the satellite spins counter-clockwise at 100 rpm around its longitudinal axis, which is aligned with the Earth's rotational axis. The MSG satellites are placed in orbit at 0 degrees longitude, like the first generation Meteosats, but can be moved up to 50 degrees east or west if required. The Spinning Enhanced Visible and InfraRed Imager (SEVIRI) has twelve spectral channels which provide precise data throughout the atmosphere. Eight of the channels are in the thermal infrared, providing data about the temperatures of clouds, land and sea surfaces. One of the channels is called the High Resolution Visible (HRV) channel, and has a sampling distance at nadir of 1 km, as opposed to the 3 km resolution of the other visible channels. The improved horizontal image resolution of 1km for the visible light spectral channel also greatly aids weather forecasters in detecting and predicting severe weather. The data channels used for the GRIP Field Experiment were 1, 6, and 9. More information on the Meteosat spectral channels can be found on page 19 of the MSG Level 1.5 Image Data Format Description document. The Level 1.0 image data are acquired by the Spinning Enhanced Visible and IR Imager (SEVIRI) of the MSG satellites. Level 1.5 data are derived from the Level 1.0 data. EUMETSAT corrects in real-time each received Level 1.0 image for all radiometric and geometric effects and geolocates it using a standardized projection. Nominally the full Earth disk is covered for all image channels except HRV. The nominal repeat cycle duration providing this Earth coverage is 15 minutes. Channels 1,6, and 9 are are included in this GRIP dataset. The native Level 1.5 data is distributed as MSG Ground Segment packets. The actual data content of the Ground Segment packets is either:
These data are in a structure that does not directly correspond to the native format, but which is a derived one, with a continuous image array of a single spectral channel. The format of the Header and Trailer information is, however, unchanged. In depth information about the EUMETSAT Level 1.5 MSG Level 1.5 data format can be found here: MSG_Level_1_5_Image_Data_Format_Description.pdf The raw image files are converted to PNG (Portable Network Graphics) format for ease of displaying using conventional browsers. The image projection being applied nominally is the geostationary projection center (0° longitude, 0° latitude), with an image size of 3712 lines by 3712 columns (N-S by E-W), the sampling distance defined to be exactly 3 km by 3 km at the sub-satellite point. The data and browse files are named as the examples below: data:
browse:
where:
The data producer is:
To order these data or for further information, please contact:
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