北半球10hPa极地涡旋环流指数定义及分析  

The Circulation Indices of Polar Vortex on 10hPa in Northern Hemisphere and Preliminary Analysis

作　　者：管树轩[1] 王盘兴[1] 麻巨慧[1] 李丽平[1] 

机构地区：[1]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《高原气象》2009年第4期777-785,共9页Plateau Meteorology

基　　金：科技部国家支撑计划项目"南方冰雪灾害的天气成因研究"资助

摘　　要：利用NCEP/NCAR再分析值10 hPa月平均高度场资料定义和计算了1948—2007年北半球10hPa极地涡旋的强度指数（P）、面积指数（S）和中心位置指数（λc,φc）。用它们分析了北半球10 hPa极地涡旋的季节变化和年际异常规律,研究了它们与全球增暖、臭氧（O3）异常和极地涛动（AO）的关系。结果表明：（1）北半球10 hPa层高纬6～8月为反气旋（A）控制;9月～3月为气旋（C）控制。春季环流转型（C→A）缓慢;秋季转型（A→C）迅速。（2）P、S异常的年际变化具有同步性,故异常分析仅取P进行。隆冬（1月）P的异常主要表现为年际尺度（10年以下周期）振荡,不存在明显的年代际变化;盛夏（7月）极地反气旋强度年代际变化显著。（3）隆冬极地气旋中心位置的异常明显大于盛夏反气旋。（4）极区中平流层平均气温的演变1、7月迥异,但它们与P的演变同步;与全球增暖趋势无显著相关,但7月P与O3异常有显著正相关。（5）隆冬（1月）10 hPa气旋强度指数P与极地涛动指数AO存在显著正相关,故可用10 hPa↑～P′表示AO。A set of circulation indices are defined and calculated to characterize monthly mean polar vortex at 10 hPa geopotential heights in the Northern Hemisphere, including area- （S）, intensity- （P） and centre position-（λc,φc）-indices by use of 10 hPa 1948-2007 NCEP/NCAR reanalyzed value monthly height data. These indices series are used to investigate the seasonal variation and interannual anomaly of polar vortex, together with the relation to global warming, ozone anomaly and AO. The results are as follows： （1） there is anticyclonic（cyclonic） from June to August（from September to March）. The change of autumn circulation pattern is slower than spring. （2） P can be replaced by S in analysis due to the interannual synchronal variations of the intensity and area for polar vortex. The interannual（interdecadal） variation of P anomaly is significantly in January（July）. （3） The anomalies of system centre position in January are more evident than in July. （4） The variations of mean temperature at mid-stratosphere in the vicinity of pole zone in January are different from in July, but they are synchronal with corresponding P and not significantly correlative with the trend of global warming. However the relationship between P and total ozone in July are obviously. （5） There is so notable correlation between P and AO that P can represent AO.

关 键 词：10hPa极地涡旋系统 环流指数 全球变暖 臭氧异常 北极涛动 

分 类 号：P459.4[天文地球—大气科学及气象学]