Abstract 088

Abstract ID: 088

Evaluation of GEOS -S2S Version 3 Forecast System

Lead Author: Li Ren
NASA/GSFC, SSAI, United States of America

Keywords: GMAO, GEOS S2S, MERRA2, coupled assimilation, forecast skill

Abstract: The Global Modeling and Assimilation Office (GMAO) has developed a new version (V3) of the Goddard Earth Observing System (GEOS) Subseasonal to Seasonal prediction (S2S) system. This new version of the coupled atmosphere-ocean data assimilation system runs with upgrades of a higher oceanic resolution, assimilation of satellite sea surface salinity, new ensemble forecast strategy, and “dual ocean” replay the GEOS Atmospheric Reanalysis, the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA 2). This new “weakly” coupled reanalysis is designed to provide dynamically consistent air/sea coupled model results for a wide range of scientific studies. In addition, this coupled system will provide initial conditions for the next generation of subseasonal to seasonal forecasts from GMAO (S2S-V3). The coupled assimilation system assimilates all available in situ temperature and salinity profiles, along-track absolute dynamic topography, and sea surface salinity from Aquarius, SMAP and SMOS. First, we evaluate the ocean data assimilation statistics over depth for temperature and salinity, SST, SSS, mixed layer depth, upper ocean heat content, and water masses, globally and regionally. Next, we demonstrate the improved forecast skill initialized from coupled assimilation analysis over our current NMME forecast system, S2S-V2.

Andrea Molod (NASA/GSFC)
Eric Hackert (NASA/GSFC)
Santha Akelia (NASA/GSFC)
Lauren Andrews (NASA/GSFC)
Donifan Barahona (NASA/GSFC)
Anna Borovikov (NASA/GSFC, SSAI)
Richard Cullather (NASA/GSFC, University of Maryland)
Robin Kovach (NASA/GSFC, SSAI)
Randal Koster (NASA/GSFC)
Young-Kwon Lim (NASA/GSFC, UMBC)
Jelena Marshak (NASA/GSFC)
Kazumi Nakada (NASA/GSFC, SSAI)
Siegfried Schubert (NASA/GSFC, SSAI)
Yury Vikhliaev (NASA/GSFC, SSAI)
Steven Pawson (NASA/GSFC)