GeoXO: NOAA’s Future Geostationary Satellite System

Abstract Geostationary Extended Observations, or GeoXO, is NOAA’s future geostationary satellite constellation, set to launch in the early 2030s and operate into the 2050s. Given changes to the Earth system, improvements in technology, and expanding needs of satellite data users, GeoXO will extend NOAA’s current observation suite by adding three new instruments and one new spacecraft. Improved versions of the imager and lightning mapper will again be placed on East and West satellites, where they will monitor severe storms, tropical cyclones, fires, and other hazards. They will be joined by an ocean color instrument designed for detection of harmful algal blooms, phytoplankton, chlorophyll-a, and other constituents. The third geostationary spacecraft will be placed in the center of the U.S. and will carry a hyperspectral infrared sounder, an atmospheric composition instrument, and potentially a partner payload. Radiances from the sounder will be assimilated into numerical weather prediction models to improve forecasts, and sounder-derived retrievals of vertical profiles of temperature and water vapor will allow forecasters to detect and track areas of enhanced instability. Retrievals of pollutants such as nitrogen dioxide and ozone from the new atmospheric composition instrument along with trace gas measurements from the sounder will be used to improve air quality monitoring, forecasts, and warnings in addition to climate monitoring. Once complete, the GeoXO constellation will contribute to an international “geo ring” of satellites that will be used for worldwide weather, oceans, climate, and air quality monitoring. This revolutionary new geostationary satellite constellation will provide critical observations for a changing Earth system.