热带气象学报2013，Vol.29Issue(1)：17-27,11.DOI:10.3969/j.issn.1004-4965.2013.01.003
1949-2008年热带气旋在中国大陆活动的统计特征及环流背景
CHARACTERISTICS OF TROPICAL CYCLONE ACTIVITIES OVER MAINLAND CHINA IN 1949-2008 AND ASSOCIATED BACKGROUND CIRCULATION
摘要
Abstract
With Tropical Cyclone(TC) Yearbooks data from 1949 to 2008, statistical analyses are performed to sttidy the climatic features of TCs which made landfall in the mainland of China, including its landfalling frequency, spots, intensity as well as track, moving speed, sustention and dissipation etc. Results indicate that there are 542 TCs made landfall in China and about 71 % of the total attacked the mainland during the past 60 years. Regions most frequently affected by TCs are the southwest of Guangdong and south of Guangxi, while Jiangxi and Anhui are the inland areas with highest frequency. The annual average landfalling latitude is 24.1°N, with northern tendency after the 1990s till 2006. TCs with different intensity weaken significantly in the first 6 hours post landfall, but the decay ratios become consistent after 24 hours. In addition, there is no obvious interannual variability of TCs' durations over land. However, from 2004 to 2008, TCs sustained longer over land than the normal (25 hours). Generally, TCs move more slowly when making landfall, less than 20 km/h, but accelerate after landfall. And they have the fastest moving speed over the northeast of China, exceeding 45 km/h. Finally, 34% of mainland landfalling TCs re-enter the sea, 6% enter other countries and 60% disappear in the mainland with 65% hereinto dissipate along the coast. In addition, with the NCEP reanalysis data, composite analyses are carried out to study the large-scale circulation for TCs with three different tracks respectively: westward, northwestward and recurvature. The main differences are associated with the pattern of the western North Pacific subtropical high, westerly trough, and upper-level flows. TCs with recurving tracks are related closely to the development of Tibetan High and westerly trough at mid-latitude. A common feature for all TCs is that there are vortices over the Bay of Bengal and southwest low-level jet stream coupled with TC circulation, indicating that monsoon activities and water vapor transport are important to TCs' activities after landfall. Moreover, two groups of typhoons with similar tracks in different seasons are analyzed by comparison. It is found that the interaction between the TC and westerly trough is a key factor for TC recurvature track in different season.关键词
热带气旋/气候特征/环流背景/中国大陆Key words
tropical cyclone/ climatic characteristics/ background circulation/ landfall分类
天文与地球科学引用本文复制引用
魏娜,李英,胡姝..1949-2008年热带气旋在中国大陆活动的统计特征及环流背景[J].热带气象学报,2013,29(1):17-27,11.基金项目
国家重点基础研究发展规划项目(2009CB421504) （2009CB421504）
国家自然科学基金项目(40675033、40730948) （40675033、40730948）
中国气象科学研究院基本科研业务费专项(2007Y006)共同资助 （2007Y006）
