摘要
利用浙江省10个站的温度和降水资料、国家气候中心160站的降水资料、NOAA的ERSST和OLR资料及NCEP再分析资料,对2013年7至8月发生在浙江省的持续高温干旱天气过程的基本特征和环流异常进行了分析。结果表明:浙江省各站的高温日数、高温持续日数、持续无降水日数、干旱指数都远超历史同期纪录,降水较常年偏少3成以上。南亚高压强度偏强,面积偏大,东侧脊点位置偏东;西太平洋副高强度偏强,西侧脊点位置偏西;东亚季风异常偏强及其造成的水汽辐合偏弱,是高温干旱天气产生的重要原因。其中7月底西太平洋副高的异常西伸及8月异常持续偏西对浙江8月持续高温干旱的发生起了决定性作用,这与同期热带西太平洋暖池区增暖、菲律宾周围对流活动加强有关,后者通过EAP/PJ遥相关型对前者产生影响。
Based on the temperature and precipitation data of 10 stations in Zhejiang, the precipita- tion data of 160 stations from National Climatic center, the ERSST and OLR data from NOAA and the NCEP reanalysis data, the general characteristics and circulation anomaly of the continuous high tempera- ture and drought weather occurred in Zhejiang during July to August, 2013 are analyzed. Results show that high-temperature days, persistent high-temperature days, persistent no-precipitation days and drought index greatly exceed those in history. The rainfall was more than 30% below the historical aver- age. The more intensive South Asia high and eastward position of the east ridge point, the more remarka- ble West Pacific Subtropical high （WPSH） and westward position of the west ridge point, the anomalous strong South Asian summer monsoon and as a result its weaker moisture convergence were all the main reasons bringing about the high-temperature and drought weather. The anomalous westward of the WPSH occurring at the end of July and its anomalous persistence in August played a decisive role in the lasting high temperature and drought in Zhejiang. Moreover, the WPSH anomaly was related to the warming of the western Tropical Pacific warm pool and intensive convection in the area around the Philippines at the same time, and the latter affected the former by EAP/PJ pattern.
出处
《气象科学》
北大核心
2015年第2期140-149,共10页
Journal of the Meteorological Sciences
基金
国家自然科学基金资助项目(41375063)
关键词
高温
干旱
南亚高压
东亚夏季风指数
High temperature
Drought
South Asia high
East Asian summer monsoon index
作者简介
通信作者：张立凤．Zhanglif@yeah．net
