NOAA satellites have been monitoring Earth’s weather and environment since 1970, which also happened to be the year the first official Earth Day took place! Building upon early pioneering efforts by NASA and others, today’s advanced satellites provide critical information that feeds forecast models and warns us of severe weather and environmental hazards. NOAA operates two types of satellites that monitor the Earth: polar-orbiting and geostationary.
NOAA’s polar-orbiting satellite fleet is called the Joint Polar Satellite System (JPSS), and includes the NOAA-20, NOAA-21, and the NOAA/NASA Suomi NPP satellites. These satellites complete 14 orbits over the Earth’s poles each day in Low Earth Orbit, 512 miles above the surface. As they orbit, the Earth rotates beneath them, which results in each pass capturing a new view or “swath” of the planet. These are stitched together to create a full view of the entire planet twice daily.
Global data from polar-orbiting satellites, including atmospheric temperature and moisture profiles, are used in numerical weather models to generate weather forecasts up to seven days in advance. Polar-orbiting satellites observe the whole world from closer up and in higher resolution than geostationary satellites, allowing for a more detailed view of weather patterns and environmental conditions.
NOAA’s Geostationary Operational Environmental Satellites (GOES)–R Series is the Western Hemisphere’s most sophisticated weather-observing and environmental-monitoring system. The GOES-R Series is made up of four satellites: GOES-R, -S, -T, and -U, which were renamed GOES-16, -17, -18, and -19 respectively, once in orbit. Currently, GOES-19 operates in the GOES East position over the Atlantic, while GOES-18 operates in the GOES West position over the Pacific. GOES-16 and GOES-17 function as on-orbit spares.
GOES satellites orbit 22,236 miles above Earth’s equator, at speeds equal to the Earth's rotation. This allows them to maintain their positions over specific geographic regions so they can provide near real-time continuous coverage of that area over time. They are also far enough away that they can see the entire Earth at once rather than in swaths. This is known as a full disk view.
GOES East and GOES West provide advanced imagery and atmospheric measurements, real-time mapping of lightning activity, and also monitor space weather that can affect us here on Earth. Together, GOES East and GOES West watch over more than half the globe—from the west coast of Africa to New Zealand and from near the Arctic Circle to the Antarctic Circle.
This year marks the 50th anniversary of NOAA’s Geostationary Operational Environmental Satellite (GOES) program. For five decades, NOAA and NASA have partnered to advance satellite observations from geostationary orbit. GOES satellites serve as sentinels in the sky, providing vital data for weather, environmental, and space weather forecasts. Each new generation of these satellites has delivered new and improved capabilities to monitor the Western Hemisphere.
NOAA also operates a deep space satellite called the Deep Space Climate Observatory (DSCOVR) at Lagrange point 1, approximately one million miles away from Earth, that also studies the sun and space weather. Onboard DSCOVR is NASA’s Earth Polychromatic Imaging Camera (EPIC) instrument that also captures imagery of Earth. Since this satellite is nearing the end of its lifespan, NOAA is planning to launch another, called SWFO-L1, later this fall.
As we celebrate Earth Day, let us marvel at the wonders of our planet and reflect on our responsibility to cherish and protect it. Together, let’s ensure that the view from space remains a symbol of hope and inspiration for generations to come.
Video Credits:
NOAA, NASA, the Collaborative Institute of Research in the Atmosphere (CIRA)
Music:
“Eternal Grove” by Andreas Viktor Patrik Ahlm [STIM]; Chalk Music [PRS]; Universal Production Music