Geostationary advanced infrared sounder radiance simulation and validation for Sandy Supplemental OSSE

As the second costliest hurricane in US history, Hurricane Sandy caused damages of more than $68 billion along with more than 286 fatalities. One of the purposes of the Disaster Releif Appropriations Act of 2013, commonly known as Sandy Supplemental, is to improve NOAA information and services for decision makers, communities and the public in preparation for high impact events like hurricanes. Under Sandy Supplemental, NOAA will develop state-of-the-art Observing System Simulation Experiments (OSSE) systems that will evaluate benefits of potential new observing systems, including future geostationary advanced hyperspectral Infrared (IR) sounders. As part of the Sandy Supplemental OSSE project, this study focuses on simulating future geostationary advanced hyperspectral IR sounder radiances, which will be assimilated to evaluate their impacts on hurricane forecasts in both regional and global numerical weather prediction models, including track and intensity. To avoid identical radiative transfer models (RTM) in both simulation and assimilation, the Stand-alone AIRS Radiative Transfer Algorithm (SARTA) coupled with a fast cloud model for cloud scattering and absorption is used to simulate all sky Atmospheric Infrared Sounder (AIRS) radiances in the Geostationary Operational Environmental Satellite (GOES)-13 orbit. Simulations are performed with the European Center for Medium-Range Weather Forecast (ECMWF) T1279 nature run (NR) as well as the experimental GEOS-5.12 NR from NASA Global Modeling and Assimilation Office (GMAO). Results are compared with GOES-13 Imager radiance observations to examine the quality of the simulation, including channels consistency, diurnal variations, cloud coverage etc. A quick regional OSSE is also performed using the ECMWF T1279 NR to investigate the potential impact of geostationary hyperspectral IR sounder on Hurricane Sandy forecast.