The Geostationary Operational Environmental Satellite (GOES) System


The geostationary operational environmental satellite (GOES) system provides vital meteorological and space weather data for North America. It is operated by the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service. GOES is the primary source of real-time images and data used by meteorologists to forecast weather and monitor severe storm development and movement. It also helps with atmospheric research, improving numerical weather prediction models, and monitoring the Earth’s surface, atmosphere, and ocean.

The GOES system comprises two satellites, one located in the east and the other in the west. They are positioned in geostationary orbit 35,790 kilometres (22,240 mi) above the Earth. This enables the satellites to regularly view the continental United States, the Pacific and Atlantic Oceans, Central and South America, southern Canada, and northern Africa.

GOES instruments observe the electromagnetic energy radiating from Earth, including visible light and thermal infrared radiation. They also observe the reflected radiation from the Sun off of Earth’s clouds and surface. Meteorologists use this information to identify cloud type and track storm movements. Surface reflectance from snow, ice, and light-colored sand is particularly noticeable on GOES visible image data, which reveals details about the structure of these materials. GOES instruments also sense solar X-rays and flares and measure the near-Earth solar-terrestrial electromagnetic environment, which is important for the operation of radio wave communication and navigation systems and to astronauts on the International Space Station and high altitude aviators.

Each GOES satellite has an Imager and a Sounder instrument, which work together to produce a variety of products. The Imager detects and measures infrared radiation from the atmosphere and surface, while the Sounder records vertical atmospheric temperature, moisture and ozone distribution. The Imager and Sounder are synchronized to provide a seamless, three-dimensional picture of the atmosphere.

The GOES-I and GOES-M series satellites have an additional feature: the S&R capability, which is capable of detecting distress signals from ships in the water. This function was first introduced on GOES-7 as a research/demonstration program, but it is now an operational service provided by the GOES-I-M series.

GOES data are also available to the general public through numerous websites and services. These sites are not considered official NOAA links and should be used for non-operational purposes.

In addition to providing imagery and data to the public, some GOES-I-M satellites have the ability to respond rapidly to specific requests for data from the National Weather Service. This is done through a system called “advanced event mode.” When the conditions required by the request are met, the satellite transmits data to the DCS in a different mode than normal. This mode can increase the frequency of data transmission, change the data format, or perform other functions. It is activated by a command sent from the NOAA Satellite Operations Control Center (SOC) in Suitland, Maryland. Currently, advanced event modes are active on GOES-13, GOES-15, and GOES-16.