阿留申低压一组环流指数与北半球海气异常的关系

发布时间：2018-06-04 22:41

本文选题：环流指数 + 阿留申低压　；参考：《大气科学学报》2017年05期

【摘要】：定义了一组描述冬季季、月平均1 000 h Pa位势高度上阿留申低压(Aleutian low,AL)状态的新环流指数,包括强度指数P、面积指数S及中心位置指数(λ_c,φ_c)。采用1948/1949—2007/2008年60个冬季的NCEP/NCAR平均高度场资料计算了上述环流指数,并据此分析了AL的气候及异常规律。结果表明:1)AL在1月最强,中心偏南、偏西;12月最弱,中心偏北、偏东;2月居中。2)AL指数P与λ_c之间存在负相关,强年(庥'0)偏东(λ'0)、弱年偏西。AL年代际变化主要表现在自20世纪70年代以来持续偏强、偏东,但近年有反转的迹象。3)AL在强El Ni泺o年偏强、偏东,在强La Ni泺a年相反,该关系自1975年以后尤其明显;AL与中纬太平洋海表温度(SST)存在显著正相关,SST负异常年AL东移加强,反之亦然。4)AL指数P与同期北半球中高纬气温、降水的显著相关区呈现"+-+"大圆波列分布,相关中心分别位于中纬度北太平洋、北美西北部、北美南部,与太平洋—北美遥相关型(PNA)接近。
[Abstract]:A set of new circulation indices describing the Aleutian low ALL state at the monthly mean 1 000 HPA geopotential height in winter season are defined, including the intensity index P, the area index S and the 位 C, 蠁 che. The circulation index is calculated by using the NCEP/NCAR mean height field data of 60 winters of 1948 / 1949-2007 / 2008, and the climatic and anomalous laws of AL are analyzed. The results showed that the strongest in January, the center was southward and westward, the weakest in December, the center was north and east, and in February there was a negative correlation between P and 位 c. The Interdecadal variation of the strong year (Xiu) is mainly reflected in the strong and eastward trend since the 1970s, but in recent years there are some signs of reversal in the strong El Ni Loro year, and in the strong La Ni happy year, the opposite is true in the strong La Ni happy year. It is especially obvious that there is a significant positive correlation between AL and SSTs in the mid-latitude Pacific Ocean SST since 1975, and the eastward shift of the negative SST anomaly to the east, and vice versa .4N AL exponent P and the mid-high latitudes temperature in the Northern Hemisphere in the same period. The significant correlation area of precipitation is "-" large circular wave train distribution, the correlation center is located in the mid-latitude North Pacific Ocean, northwest North America, and South North America, which is close to the Pacific and North America teleconnection type (PNA).
【作者单位】：南京信息工程大学大气科学学院;广西玉林气象局;吉林省气象局;中国气象局气象干部培训学院;
【基金】：国家自然科学基金资助项目(41376039) 气象灾害教育部重点实验室(南京信息工程大学)开放课题基金资助项目(KLME1311)
【分类号】：P732

【相似文献】