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 Relevant information about this satellite page
The current generation of weather satellites are developed and supported by funding from the National Oceanic and Atmospheric Administration (NOAA). This generation of Geostationary Operational Environmental Satellites (GOES), known as the GOES-R Series, are the most advanced fleet of geostationary weather satellites ever to be deployed. These geostationary satellites circle the Earth in geosynchronous orbit, meaning they orbit the Earth’s equatorial plane at a speed that matches the Earth’s rotation. This allows them to stay in a fixed position with respect to a point on the Earth’s surface. Two GOES satellites are always in operation at any given time; one is situated over the Pacific providing views of Hawaii and the western United States, and one is situated over the Atlantic, providing views of the eastern United States and the Atlantic Ocean. GOES satellites are designated with a letter prior to launch and renamed with a number once they reach orbit. GOES-R and GOES- S, the current satellites in orbit, are now referred to as GOES-16 (over the Atlantic Ocean) and GOES-17 (over the Pacific Ocean) respectively. More information can be found on the GOES-R series webpage: https://www.goes-r.gov/mission/mission.html
The GOES-R generation of weather satellites measure 16 different channels, or ABI (Advanced Baseline Imager) bands. They are in the following portions of the electromagnetic spectrum:
     Band 1: Visible – Blue Band (0.47 microns)
     Band 2: Visible – Red Band (0.64 microns)
     Band 3: Near-Infrared – Veggie Band (0.86 microns)
     Band 4: Near-Infrared – Cirrus Band (1.37 microns)
     Band 5: Near-Infrared – Snow/Ice Band (1.6 microns)
     Band 6: Near-Infrared – Cloud Particle Size Band (2.24 microns)
     Band 7: Infrared – Shortwave Window Band (3.9 microns)
     Band 8: Upper Troposphere Water Vapor (6.2 microns)
     Band 9: Mid-Level Troposphere Water Vapor (6.9 microns)
     Band 10: Low-Level Troposphere Water Vapor (7.3 microns)
     Band 11: Cloud Top Phase (8.4 microns)
     Band 12: Ozone (9.6 microns)
     Band 13: Clean IR Longwave (10.3 microns)
     Band 14: IR Longwave (11.2 microns)
     Band 15: Dirty IR Longwave (12.3 microns)
     Band 16: CO2 Longwave IR (13.3 microns)
The Satellite page on this site provides real-time satellite images from many of the bands listed above. These images update on a 5-minute basis and include close-up, high resolution images. The resolution capability of these satellites is approximately 0.5-1 km for the visible imagery and 1 km for the other bands. The images available here are remapped to a Lambert Conformal projection.
The visible (color) imagery is a combination of bands 1, 2, and 3 and gives a "true color" perspective. The visible (grayscale) imagery shows band 2 only. The visible images display the earth very similarly to how humans see it with their eyes or how typical cameras view it. Clouds and snow appear bright white (high albedo/reflectance) but oceans and trees are much darker.
The infrared imagery shows band 14. This band is calibrated to temperature and expressed in degrees Celsius. Where clouds exist, the temperature is that of the tops of clouds. Where clouds do not exist, the temperature is that of the ground or the water. This information is very valuable to aviators since clouds with cloud top temperatures below 0°C may indicate that an aircraft icing hazard exists. Generally speaking, the warmer an object, the more infrared energy it emits. The satellite sensor measures this energy and calibrates it to temperature using a very simple physical relationship (Planck's Law). In the real world, clouds that are very high in the atmosphere are generally quite cold (perhaps -50°C) whereas clouds that are very near the earth's surface can be quite warm (perhaps +5°C). Likewise, the land may be even warmer than the lower clouds (perhaps +20°C) in the summer. Those colder clouds emit much less infrared energy than the warmer clouds and the land emits more than those warm clouds. The data measured by the satellite are calibrated and colorized according to the temperature with red shades representing higher (warmer) temperatures and blue shades representing lower (cooler) temperatures. If the temperature of the atmosphere decreases with height (which is typical), a user can get an idea of which clouds are high-level and which are low-level based on the cloud top temperature.
The low/mid/high water vapor imagery shows imagery from bands 10, 9, and 8 respectively. The water vapor bands are also calibrated to temperature in degrees Celsius but are typically interpreted more by their colors. Warm colors (oranges and reds) indicate very dry regions and areas that are likely to have few to no clouds whereas cool colors (purples, blues, and greens) indicate regions with higher moister contents and may indicate areas of cloudiness. Gray colors fall in between. The most useful tidbit to be gained from the water vapor images is the locations of storm systems and the jet stream.
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This material is based upon work supported by the National Center for Atmospheric Research, a major facility sponsored by the National Science Foundation and managed by the University Corporation for Atmospheric Research.
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