Analysis with Energetics Method Associated with a Heavy Rainfall in Warm Region of Western Sichuan Plain

By using 1°×1°NCEP reanalysis data, an analysis have been performed, with energetics method, to study a heavy rainfall in warm region occurred on 14th August 2015 in westerm plain of Sichuan.The results show that the total energy accumulated in the morning and released in the afternoon.The total energy increased over time from north to south, in keeping with rainfall area moving from chengdu to Meishan and Leshan.The maximum of total energy appeared at two in the afternoon in area near by 30°N, in accordance with heavy rainfall appeared in Meishan at the same time.Because the latent heat energy had the same change trend with total energy on 14th day, and its change value was close to that of total energy at different times, the change of latent heat energy was the main factor which led to the change of total energy.The latent heat energy was the main contributor of this heavy rainfall in westerm plain of Sichuan.The latent heat energy increased apparently, which was advantagous to precipitation.There was a good relationship with latent instability area and rainfall area.The saturation energy difference was small and convective instability energy increased, which was beneficial to precipitation.The convective instability energy and latent instability energy increased significantly, and energy balance height reached near by 200hPa, which caused large areas of heavy rainfall.