The GOES (GEOstationary Operational Environmental Satellite) system provides vital real-time weather data to NOAA’s National Weather Service and Meteorological Services of Canada as well as atmospheric science research and environmental sensor design.
The data is a lifeline that supports severe storm tracking, meteorology research, and weather forecasting and monitoring of the Earth’s land, atmosphere, and oceans. The data also support aviation safety by monitoring volcanic activity and associated ash plumes.
GOES is comprised of a fleet of geostationary satellites and ground-based elements that work together to provide a continuous stream of data. The satellites are in a geostationary orbit that keeps them over the same geographic area over time.
They are equipped with instruments that measure Earth-emitted and reflected radiation from which weather information like temperature, wind speed, moisture, and cloud cover can be determined. The data is transmitted to a network of meteorology radars and weather centers where it can be interpreted and used for forecasting.
A typical GOES satellite has two primary payload instruments: the Imager and the Sounder. The Imager is a multichannel instrument that senses visible and infrared radiant energy, primarily from the Earth’s surface and atmosphere. The Sounder, on the other hand, measures vertical atmospheric temperature and moisture profiles, and provides a variety of environmental parameters, including ozone distribution.
Both of these instruments operate with a servo-driven, two-axis gimballed mirror system (whiskbroom type) in conjunction with a 31 cm Cassegrain telescope. This combination allows a GOES satellite to scan the entire disk of the Earth, day and night, in as little as 30 seconds.
The satellites are also equipped with the Space Environment Monitor (SEM) instrument package of NOAA’s Space Environment Center (SEC). This instrument measures the solar wind particle flux, its variations, and resulting effects on the near-Earth solar-terrestrial electromagnetic environment.
GOES satellites are constantly scanning the atmosphere, looking for the atmospheric “triggers” that can lead to the formation of severe storms such as tornadoes, hail storms and hurricanes. They can also track wildfires to detect their growth, estimate rainfall during thunderstorms for flash flood warnings, and help meteorologists issue snow storm warnings.
In the spring of 2020 GOES-16 and 17 helped meteorologists track the movement of wildfires, while during the busy hurricane season they provided live images that were used to help forecast the progression and strength of those storms. During this record-setting Atlantic storm season they also tracked 30 named storms, six of which were major hurricanes.