Comparative Characteristics Of Northern Hemisphere And Local Summer Convective Precipitation

Based on 3-hour CMORPH satellite precipitation data during 2003-2014 JJA and basic climatology statistic methods, convective precipitation characteristics of spatial distribution, diurnal variation and its response to the El Nino are analysed. Based on 1-hour representative sites precipitation data in eastern China (Qiqihaer, Beijing, Nanjing, Guangzhou) during 1955-2012 JJA, climatology characteristic of convective precipitation and variation characteristic of convective precipitation for the nearly 58 years are compared, and the contributing factors of short-time heavy precipitation in Guangzhou are conducted. The results show that:(1) Convective precipitation is mainly distributed on the ocean near ITCZ, central North America, Southeast Asia and tropical Africa etc. The probability of extreme strong convective precipitation of land is greater than that of ocean. Diurnal variation of convective precipitation is presented with two peaks on land, in the evening(18-20 LST) and midnight(22-01 LST). And its occurrence probability is lager between midnight and morning on ocean. The convective precipitation increases on ocean and decreases on land in developing years of El Nino, while the weakening years are opposite. Nonconvective precipitation on the eastern part of China is more during the El Nino years than that during normal years, and the results are different form the response of the convective precipitation.(2) Averaged frequency and intensity of convective precipitation and precipitation in Guangzhou are the largest in the four sites, and in Qiqihaer are the smallest. The intraseasonal variation trend of precipitation and convective precipitation frequency is related to summer rainfall migration in eastern China. Convective precipitation frequency at 14 to 22 PM at night is significantly in Beijing and Nanjing, and in other sites is relatively not obvious.(3) The linear trend of convective precipitation for the four representative sites is more significant than that of non convective precipitation, it shows that convective precipitation is more sensitive to climate change. Beijing and Qigihar convective precipitation variation trend is consistent with the water vapor, while Nanjing and Guangzhou convective precipitation change trend is consistent with the change trend of temperature.