内蒙古高温酷暑天气的气候学特征和环流类型

利用1971—2008年内蒙古117个观测站日最高气温资料,结合同期的NCEP再分析资料,分析了内蒙古高温酷暑天气的气候学特征。结果表明：内蒙古高温酷暑天气地域差异大,高温中心在阿拉善盟沙漠地区的拐子湖,年平均35℃高温日数达32天,也是全国的高温区之一;内蒙古的高温天气年日数有增长趋势,高温酷暑的影响在增强;内蒙古高温酷暑集中出现在盛夏季节6—8月,7月发生最多,占一半以上;最高气温出现在每日的14—17时,气温日较差大,多为干热天气。通过对内蒙古较大范围的64次高温天气过程分析总结,将内蒙古高温酷暑天气分为蒙古暖脊型、贝加尔湖高压坝型、副高西进型、乌拉尔山高脊型4个类型。大陆暖高压脊的强烈发展和维持与内蒙古高温酷暑天气密切相关。

The Climatological Characteristics and Circulation Pattern of the Megathermal Weather in Inner Mongolia

By using observation data of 117 observation stations from1971 to 2008,combined with NCEP reanalysis data,the climatological characteristic of the megathermal weather was analyzed in Inner Mongolia.The result shows that： It has great differences among each region;the high temperature center is in Guaizihu which is in the Alashan desert where there are annual mean more than 32 days above 35℃.Plus,it is one of the high temperature region in China.The trend and influence of annual megathermal days are increasing in Inner Mongolia.The megathermal weather is mainly in midsummer from June to August,and July occurs most,.it is half part.the highest temperature appeared in the daily 14 to 17 and the daily range of temperature is large,so in most cases,it is hot and dry.By analyzing the 64 megathermal weather processes in Inner Mongolia,the megathermal weather is divided into 4 types,Mongolia warm ridge,Baikal high pressure dam,subtropical high moving to the west and Ural anticyclonic ridge.The strong development and maintenance of the continental warm high ridge has close relationship with the megathermal weather in Inner Mongolia.