大气科学2012，Vol.36Issue(6)：1123-1134,12.DOI:10.3878/j.issn.1006-9895.2012.11192
2010年秋、冬季节华北持续性干旱的气候成因分析
Possible Causes of Persistent Drought Event in North China during the Cold Season of 2010
摘要
Abstract
Anomalies in the sea surface temperature (SST) and atmospheric circulation that are linked to the drought event in North China during the cold season spanning 2010-2011 are discussed. The possible impacts of the Arctic Oscillation (AO) and La Nina are also addressed in the framework of historical analog analysis based on daily station-observed and NCEP/NCAR reanalyzed data sets. The results suggest that the precipitation in North China exhibits a downward trend over the past decades, however, the extreme drought event occurred during the cold season of 2010 has been mainly affected by the negative phase of the AO and the stronger La Nina event. Statistical analysis suggests that during the negative phase of the AO, the geopotential height at 500 hPa decreases around Lake Baikal, the Ural blocking high develops, and meridional circulation anomalies prevail over East Asia. Such high-latitude circulation may enhance the cold surge around Lake Baikal and cause it to shift southward, indirectly causing a cold, dry climate in North China. During La Nina years, however, the cooling of the SST in the Nifio3.4 region weakens the western North Pacific subtropical high and directly blocks the southward moisture flux supply. In contrast to historical drought cases, the stronger and persistent negative phases of the AO and the La Nina event pushed the cold front much further south, and the two together caused the persistent drought event in North China during the cold season of 2010.关键词
华北干旱/极端气候事件/北极涛动/La Ni(n)a事件Key words
drought in North China, extreme climate event, Arctic Oscillation, La Nina分类
天文与地球科学引用本文复制引用
沈晓琳,祝从文,李明..2010年秋、冬季节华北持续性干旱的气候成因分析[J].大气科学,2012,36(6):1123-1134,12.基金项目
国家自然科学基金资助项目40921003、90711003,公益性行业(气象)科研专项GYHY200906017,中国气象科学研究院基本科研业务项目2010Z001、2010Z003,中国科学院战略性先导科技专项XDA05090408 （气象）
