Sensitivity of Summer Monsoon Precipitation over East Asia to Convective Parameterization Schemes in RegCM3

Abstract

This study investigates some of the important characteristics of summer monsoon circulation and precipitation over East Asia in general and Korea in particular using the recent version of NCAR Regional Climate Model (RegCM3). RegCM3 has been integrated at 27 km horizontal resolution over the East Asian domain for the period from 1998 to 2002 (5 years). The important characteristics of temperature and wind at upper and lower levels and precipitation simulated by the RegCM3 over South Korea are examined in detail using different convective parameterization schemes namely, mass flux schemes, a simplified Kuo-type scheme and Emanuel (EMU) scheme. The monsoon circulation features (wind and temperature) simulated by RegCM3 are compared with those of the NCEP/NCAR reanalysis (Kalnay et al. 1996) and simulated summer precipitation in JJA (average of June to August) over Korea (KMR) is validated against the observation from Korea Meteorological Administration (KMA). Validation of simulated precipitation with KMA shows that the use of the Arakawa and Schubert (AS) and EMU convection schemes are more close to the KMA. The statistical analysis (area average precipitation, standard deviation and correlation analysis) also indicates that the use of EMU and AS schemes perform better over East Asia particularly over Korea.