1971-2014年新疆区域寒潮气候特征

利用1971-2014年新疆105个台站逐日最低气温资料,分析了新疆寒潮天气的时空变化特征.结果表明:①新疆单站寒潮北疆多、东疆次之、南疆少,阿勒泰地区发生频次最高,其次是哈密北部、巴音布鲁克和塔城大部地区,南疆中西部地区发生频次最少.新疆区域寒潮天气冬季最多、秋季和春季次之,2月发生频次最高;春季寒潮主要集中在3-4月,秋季寒潮主要在10-11月.②新疆寒潮影响区域主要在北疆地区,其次是东疆、南疆东部,南疆西部影响次数最少.春季主要影响区域为北疆东部、沿天山一带和南疆东部;秋季为东疆、北疆沿天山以及北疆东部和北部地区;冬季为北疆东部和沿天山一带.③新疆区域寒潮过程一般持续3～7d,过程极端最低气温主要出现在寒潮爆发当天或次日,极端气温出现时间延迟天数不超过4d.寒潮过程最低气温24 h平均降幅在10.7℃,最大19.3℃,单站最大25.3℃;寒潮过程平均降温14℃,最大达18.8℃,单站最大32.7℃.

Climatic Characteristics of Cold Wave in Xinjiang during the Period of 1971-2014

In this paper,the spatiotemporal variation of cold wave in Xinjiang was analyzed based on the daily minimum temperature data from 105 meteorological stations in Xinjiang,and the cold wave was classified according with the international standard.The results showed that the cold wave occurred most frequently in north Xinjiang,followed by that in east Xinjiang,and then in south Xinjiang.The cold wave frequency was the highest in Altay,followed by that in north Hami,Bayinbuluke of Bayingolin Mongol Autonomous Prefecture and some parts of Tacheng,and it was the lowest in central and western parts of south Xinjiang.The cold wave in Xinjiang occurred mostly in winter,and then in autumn and spring.Its frequency was the highest in February.The spring cold wave occurred in March and April,and the autumn one in October and November.The affecting areas of cold wave were mainly distributed in north Xinjiang,and then in east Xinjiang and south Xinjiang.The main affecting areas of spring cold wave were distributed in the east of north Xinjiang and south Xinjiang and along the Tianshan Mountains.The affecting areas of autumn cold wave were distributed in east Xinjiang,along the Tianshan Mountains,and the east and north of north Xinjiang.The affecting areas of winter cold wave were in the east of north Xinjiang and along the Tianshan Mountains.The cold wave duration was generally for 3-7 days in Xinjiang.The extreme minimum temperature occurred usually on the same day or after two days of cold wave occurrence,and the delay time was shorter than 4 days.During the cold wave process,the minimum temperature was averagely decreased by 10.7 ℃ in 24 hours,19.3 ℃ in maximum,and 25.3 ℃ at single station.During the cold wave process,the air temperature was averagely decreased by 14 ℃ in 24 hours,18.8 ℃ in maximum,and 32.7 ℃ at single station.