大气科学2009，Vol.33Issue(6)：1319-1332,14.
4～5月南亚高压在中南半岛上空建立过程特征及其可能机制
Characteristics of the South Asia High Establishment Processes above the Indo-China Peninsula from April to May and Their Possible Mechanism
摘要
Abstract
In terms of the NCEP/NCAR daily-mean reanalysis data (1975-2005), it is found that the upper tropo-sphere anti-cyclone to the east of the Philippines break into two portions, the west anticyclone is above the Indo-Chi-na Peninsula (ICP) while the east one still stays above the ocean to the east of the Philippines. The South Asia high (SAH) forms by the reinforcement of the west anticyclone. The formation and strengthening of the ICP upper anti-cyclone and the weakening and vanishment of the anticyclone above the ocean to the east of the Philippines occur simultaneously, which composes the chief characteristics of the SAH establishment processes above the ICP from A-pril to May, while the primary impact factor of the processes is the variation of the diabatic heating condition on the south of the Asian continent. With the northward propagation of the convection along the Asian-Australian "Land Bridge" and the buildup of the ICP convection, the upward motion over the ICP and the upper troposphere diver-gence strengthen, so that west center forms and the SAH establishes initially. Whereafter the heat source which has been on the ocean to the east of the Philippines withdraws eastward to the east of 150°E suddenly, the ICP heat source becomes the leader, which stimulates a cyclonic circulation to the east of the heating zone in the upper tropo-sphere that results in the abruption of the SAH near 120°E. Then because of the strengthen of the BOB-ICP convec-tion and the establishment of the BOB-ICP summer monsoon (BOB is short for Bay of Bengal), a great deal of latent heat is released above the ICP, which makes the vertical motion enhance so that the west center intensifies and moves northward. The South China Sea (SCS) convection begins strengthening at the same time, and the released latent heating can stimulate the upper-level positive vorticity variety, which makes the east center weaken and disap-pear, and the SAH establishes completely above the ICP.关键词
南亚高压/中南半岛/垂直非均匀加热Key words
South Asia high, the Indo-China Peninsula, vertical heterogeneous heating分类
天文与地球科学引用本文复制引用
刘伯奇,何金海,王黎娟..4～5月南亚高压在中南半岛上空建立过程特征及其可能机制[J].大气科学,2009,33(6):1319-1332,14.基金项目
国家重点基础研究发展规划项目2006CB403607,公益性行业(气象)科研专项项目GYHY200706005,国家自然科学基金资助项目40633018、40975057 （气象）
