Assessment of the Impact of Corrected GODAS Initial Conditions and Different Horizontal Resolutions on the CFS Hindcasts for 1981-2006; Evaluations over the Asian Monsoon Region

Soo-Hyun Yoo , Jae Schemm, and Song YangClimate Prediction Center, NCEP/NWS/NOAA, Camp Springs, Maryland 20746, USA

Data SST: Reynolds/NCEP version 2 monthly 1°x1° optimally interpolated SST

(OISST) Precipitation: monthly CPC Merged Analysis of Precipitation (CMAP) data

(144x72) 2m Temperature: GHCN/CAMs Global T2m (T126)

Summary To investigate the impact of GODAS corrections made for 1981-1990 on model climatologies and hindcast skills in 1981-2006, 15 ensemble member CFS T62L64 runs for April initial conditions are diagnosed for SST and 2m temperature.

SST hindcast skills increase significantly, especially over the tropical central Pacific and Indian Ocean.

CFS has moderate correlation skills of 2m temperature for summer and fall over the Asian monsoon region, which are noticeably enhanced by GODAS corrections.

Summary A single run for the ICs of 15 May is taken from new CFS hindcast runs with GFS07 for different horizontal resolutions, T62, T126, and T382. The experiments are integrated up to October over a period from 1981-2006.

The model climatologies for precipitation are more reasonably simulated for summer and fall over the Asian monsoon region in CFS T382.

The onset and intensity of the Indian monsoon is dominantly improved in CFS T382.

CFS has moderate correlation skills of 2m temperature for summer over the Asian monsoon region, which is noticeably enhanced in CFS T382.

Corrected GODAS Initial ConditionCorrected GODAS Initial Condition

Different Horizontal ResolutionsDifferent Horizontal Resolutions