Seasonal prediction systems based on CCSM3 and their evaluation

Abstract

ABSTRACTIn this study, two seasonal scale prediction systems were established based on the Community Climate System Model Version 3 (CCSM3) distributed by the National Center for Atmospheric Research (NCAR) of the United States . The initialization schemes are different between the two systems: one is based on sea surface temperature and the other is based on ocean assimilation data of the Climate Forecast System Reanalysis (CFSR). Two sets of hindcasts aiming at summer season (JJA) were generated to verify the predictive ability of the two systems for 1983–2011. The results indicate that both prediction systems perform generally well in predicting sea surface temperature anomalies (SSTA), geopotential height fields, and the typical Asian summer monsoon indices. Their prediction skills of the systems for 2‐m air temperature and precipitation are generally confined to the low and middle latitudes. The system based on CFSR ocean assimilation data obtained more accurate results for SSTA, geopotential height fields, and surface weather elements compared with the other system.