COMPARISON STUDY ON PRECIPITATION 、CLOUD AND LATENT HEAT CHARACTERISTICS OVER THE SOUTH CHINA SEA AND ITS SURROUNDING AREAS BASED ON TRMM

YE Qing-wen; LI Jiang-nan; LUO Jia-lin; DING Cheng-hui; ZHAO Yang-jie

doi:10.16032/j.issn.1004-4965.2018.03.016

Abstract：By using 1998—2013 the Tropical Rainfall Measurement Mission (TRMM)data 3A12, the three-dimensional structure and seasonal variability of the rainfall, cloud, and latent heat over the South China Sea (SCS) and its surrounding areas is investigated. For comparison, the SCS is sub-divided into four parts: the South China Region, Indo-China Peninsula, Malaysia;SCS. The results show that:(1) The rainfall distribution is highly non-uniform and changes from season to season. Overall, the precipitation is much more in summer and autumn while less in spring and winter. But in Malaysia, it is most in winter and lest summer. While in other three areas, it is most in summer. But the precipitations of both the SCS and Indo-China Peninsula reach their minimums in winter while the precipitation of the SCS reaches the minimum in spring. (2) EOF analysis shows that the first mode variance contribution rate is 57.16％, the precipitation in southern areas is higher than that in northern areas. The second mode variance contribution rate is 8.72％, shows that the precipitations of the south and the north change inversely. (3) The equatorial area is mainly distributed with convective precipitation. To the north of 23 °N, stratiform precipitation is dominant. Over the region between 5～23 °N, the precipitation ratio of two types varies with the seasons, which is obvious over land area, especially in South China, the proportion of convective precipitation over land area in summer is greater than 50％, and the proportion of stratiform precipitation in winter is greater than 80％;The proportion of convective precipitation over ocean area is generally greater than 50％, and its seasonal variation is smaller. (4) The horizontal distributions of cloud ice, cloud water, and latent heat are similar to the horizontal distribution of surface precipitation. The vertical distributions of cloud ice and cloud water in the four regions are different. Both cloud ice and cloud water increase first and then decrease with height. And cloud ice reaches the maximum at about 13km;cloud water reaches the maximum at about 2.5 km. In spring and winter, the maximum of cloud ice is distributed mainly in the Malaysian area.In summer and autumn, the maximum of cloud ice is distributed in the SCS. These four seasons all have a larger content of cloud water in the SCS. (5) Latent heat profiles have a similar bimodal structure: the first peak is at about 1～2 km and the second peak is at about 4 km. In spring and winter, the latent heat in Malaysia is much higher. And in summer and autumn, the latent heat in SCS is much higher.