Geostationary Hyperspectral Infrared Constellation: Global Observing System Simulation Experiments for five Geo-HSS instruments

While individual geostationary satellites can be highly beneficial for regional weather analyses and forecasts, their impact on global medium-range weather forecasts is limited. This study aims to use Observing System Simulation Experiments (OSSEs) to determine whether multiple geostationary satellites, placed around the equator, would have a noticeable global impact. In these OSSEs, observations are simulated from the GMAO 5-km Nature Run (G5NR), based on the observing system from 2014, degraded into a data-gap scenario with no early-afternoon orbiting satellites (2POLAR). Biases and random-errors determined from comparison to real observations are added. Then, simulated observations from geostationary Infrared Atmospheric Sounding Interferometer (IASI) instruments from five longitudes (0°, 60°, 140°, 225°, and 285°E) are assimilated into the NCEP GDAS/GFS 3D Hybrid system at T670/T254 resolution. Analysis and forecast impacts of this “Constellation” of Geo-HyperSpectral Sounders (Geo-HSS) will be discussed.