CAPABILITIES AND LIMITATIONS OF GRAPES SIMULATIONS OF EXTREME PRECIPITATION IN THE WARM SECTOR OVER A COMPLEX OROGRAPHY

作者：钟水新,杨帅,郭春伢,陈子通

摘要：A comprehensive observational study on a warm sector torrential rain(WSTR) on 20 May 2016 over south China is presented with a pioneering examination of simulation capabilities based on the Global/Regional Assimilation and Prediction System for Tropical Mesoscale Model(GRAPES_TMM). The results show that the meso-scale convective boundary formed between north wind from mountainous areas and the south wind from plain regions as well as the cold outflows boundary both contribute to the convections over Xinyi, and the convections were blocked and stayed stagnant in the trumpet-shaped topography for about 8 hours which eventually caused the torrential rains.Comparative verifications of the observational studies by simulations showed that GRAPES_TMM had better estimations of large-scale frontal precipitation than the local warm-sector torrential rains. The simulations of local torrential rains in the warm sector showed strong biases in precipitation location and amount. GRAPES_TMM also showed overestimated surface winds and a faster moving speed bias, as well as an overall underestimation of the nocturnal surface temperature during the WSTR. This work may lead to several prospective researches of its model improvements on model physics such as land surface process and PBL parameterization.

发文机构：Guangdong Province Key Laboratory of Regional Numerical Weather Prediction Laboratory of Cloud-Precipitation Physics and Severe Storms Guangdong Meteorological Observatory

关键词：WARMSECTORTORRENTIALrain(WSTR)trumpet-shapedtopographyGRAPES_TMMmesoscaleconvectiveboundary

分类号： P426.62[天文地球—大气科学及气象学]P412