宁夏5月降水变化及其对前期全球SST异常的响应分析  

Analysis on Variation of Precipitation in May in Ningxia and Its Response to Prior SST

作　　者：陈海波[1,2,3] 杨建玲[1] 严华生[2] 单新兰[3] 夏永胜[3] 

机构地区：[1]宁夏气象防灾减灾重点实验室,宁夏银川750002 [2]云南大学大气科学系,云南昆明650091 [3]宁夏气象局,宁夏银川750002

出　　处：《高原气象》2012年第3期752-759,共8页Plateau Meteorology

基　　金：国家自然科学基金项目(41065005);宁夏科技攻关项目(KGX-12-09-02);宁夏自然科学基金项目(NZ08159)共同资助

摘　　要：利用1961—2008年NCEP/NCAR全球月平均海表温度(SST)与风场再分析资料和宁夏气象信息中心提供的宁夏19个观测站的5月降水资料,采用EOF分解、相关普查和距平合成方法,分析了宁夏5月降水的时空变化规律和前期1-4月全球SST与宁夏5月降水的相关关系,寻找出SST影响降雨的显著相关区。结果表明,宁夏5月降水的EOF第一主分量的方差贡献率接近75%,时间系数分布总体略呈凸型。前期SST和5月降水之间存在显著相关关系,正相关区主要在赤道东太平洋海区、赤道印度洋海区和中大西洋海区以及阿拉斯加南部附近的海面,而显著负相关区的面积较小。2月达到90%以上置信度的相关格点数最多,4月最少。降水偏多、少年对应的SST距平合成场具有相反的特征,正、负距平中心的位置基本一致,与对应各月的相关显著区大部分重合,降水偏多年的正相关对应正距平中心,负相关对应负距平中心;降水偏少年则相反,具有很好的一致性。Based on the global monthly mean sea surface temperature（SST） and wind field from NCEP/NCAR reanalysis data and precipitation data in May at 19 meteorological stations in Ningxia, the relations of prior SST with precipitation in May and key affecting area of prior SST on precipitation were studied using the Empirical Orthogonal Function（EOF）, related survey and departure synthetic method. The results indicated that the variance contribution of EOF1 of precipitation in May was close to 75%, while the variation trend of time coefficient appeared convex type. There was significant correlation be- tween prior monthly mean SST with precipitation in May in Ningxia. There were some significant positive correlation regions in the equatorial East Pacific Ocean, the equatorial Indian Ocean and the mid-Atlantic. The area of significant negative correlation was small. The amount of grid points passed the confident level of 90% was maximum in February, hut minimum in April. The SST anomaly synthesis was contrary in more and less precipitation years in May. The positive and negative departure centres were no difference - which was similar to the related area. The positive correlation was corresponding to the positive departure centre in more precipitation year and the negative correlation was corresponding to the negative departure centre; and on the contrary in less precipitation year, there is well inconsistent.

关 键 词：SST 降水 宁夏 

分 类 号：P426.614[天文地球—大气科学及气象学]