夏季青藏高原潜热分布及其廓线特征

Characteristics of latent heating over the Tibetan Plateau during summer

利用热带测雨卫星(tropical rainfall measuring mission,TRMM)上微波成像仪(TRMM microwave image,TMI)的观测资料,首次借助卫星遥感对夏季青藏高原地区的潜热水平分布形式、潜热垂直结构及其变化特征进行了分析,并与周边地区进行了比较.潜热的水平分布形式与基于NCEP/NCAR降水资料的结果基本一致,显示了TMI反演资料在高原地区的可用性.研究结果初步揭示了夏季青藏高原上三个比较稳定的潜热加热中心,以及高原潜热廓线较为独特的单峰结构.特别在与周边区域的比较中发现,高原地区仅与印度次大陆潜热廓线的上层结构较为相似,而在6 km高度以上的对流层中高层,高原上整层的潜热加热均高于中国中东部大陆和西太平洋暖池地区,表现为显著的高空热源.

Based upon monthly mean data sets of 3-dimensional latent heating （LH） derived from TMI （TRMM Microwave Imager）, the characteristics of horizontal distributions and vertical profiles of LH over the Tibetan Plateau （TP） were investigated for the first time and compared with those of the adjacent regions. The comparison of latent spatial pattern between TMI products and that of NCEP/NCAR reanalysis data indicates an availability of TMI retrieval results in the TP area. It is shown that there are three maximum centers of LH over the plateau area and the unique LH profile with a single peak was exposed. When comparing the mean LH profile in the TP with those in the nearby areas, it is found that the LH profile over the TP is only similar to the upper part of LH profile over the Indian subcontinent. Additionally, from 6 km to the upper atmosphere, the LH at each level over the TP is generally greater than that over the eastern part of China's Mainland and the warm pool region of the Western Pacific, implying a significant heating source located at the middle and upper troposphere over the TP.