“What about the future? These [VAS Demonstration: Description and Final Report] results are the foundation for future satellites. The VAS experience suggests that extension into the microwave region, and increased spectral resolution in the infrared region, are essential so that we can obtain soundings through persistent clouds and with improved vertical resolution. Geostationary microwave instruments and high spectral resolution infrared interferometers are feasible and would be highly useful.” (Forward by Verner E. Suomi, 1985)
The 1999 ORD (Operational Requirements Document) issued by NWS already pointed out “Consequently, the temporal requirement for hourly data must be met by geostationary, rather than polar orbiting satellites, and the accuracy/vertical resolution requirements must be met by a sounder with high spectral resolution.”
NWS Position Regarding a Sounder on GOES-R Series (cira 2010): the requirements for atmospheric temperature and water vapor profiles, as stated in the Consolidated Observing user Requirements List (CORL), are still valid. Improvements in temperature and moisture soundings and other products from a geostationary platform could play a large part in meeting those requirements and enhancing the NWS capability to address the societal impacts of weather. As pointed by one HWT forecaster in 2018 report, “Assessing the vertical distribution of moisture in the environment can really help one determine the vertical structure later in the day as mixing commences.” Compared to broadband imagers and sounders, observing absorption lines is needed to meet requirements for temperature and moisture structure (or the radiances) to improve short-term weather forecasting by resolving vertical changes. Extensive studies have shown the value of polar-orbiting hyperspectral soundings in operational forecasting, and regional and global models. We expect that geostationary hyperspectral soundings will build on that success and take advantage of the increase in temporal refresh.
WMO’s implementation plan for evolution of space and surface-based sub-systems of the GOS 2005 (WMO/TD No. 1267): GEO Sounders – All meteorological geostationary satellites should be equipped with hyper-spectral infrared sensors for frequent temperature/humidity sounding as well as tracer wind profiling with adequately high resolution (horizontal, vertical and time).
This paper (Towards an Operational NOAA GEO Hyperspectral Infrared Sounder), presented by Elsayed R. Talaat, Louis W, Uccellini, and Stephen M. Volz at 2019 Joint Satellite Conference, describes technologically mature options available to fly an operational hyperspectral IR sounder over the U.S. on a geostationary satellite in the near-term, as well as the business case for doing so.
Sieglaff, Justin M.; Schmit, Timothy J.; Menzel, W. Paul and Ackerman, Steven A. Inferring convective weather characteristics with geostationary high spectral resolution IR window measurements: A look into the future. Journal of Atmospheric and Oceanic Technology, Volume 26, Issue 8, 2009, pp.1527-1541. (link)