提2015年2月大气环流的主要特征是极涡偏强且呈单极型分布，中、高纬度环流呈4波型，西太平洋副热带高压偏弱，南支槽位置与常年相近。2月全国平均气温－0．2℃，较常年同期偏高1．5℃；全国平均降水量16．3 mm，比常年同期（17．4 mm）偏少6．3％。月内我国有两次强冷空气过程；东北出现了一次较强降雪过程。下半月开始，南方雨雪过程较多且范围较大。中东部出现了2次大范围的雾或霾天气过程，并出现了1次沙尘天气。 提2015年2月大气环流的主要特征是极涡偏强且呈单极型分布，中、高纬度环流呈4波型，西太平洋副热带高压偏弱，南支槽位置与常年相近。2月全国平均气温－0．2℃，较常年同期偏高1．5℃；全国平均降水量16．3 mm，比常年同期（17．4 mm）偏少6．3％。月内我国有两次强冷空气过程；东北出现了一次较强降雪过程。下半月开始，南方雨雪过程较多且范围较大。中东部出现了2次大范围的雾或霾天气过程，并出现了1次沙尘天气。%The main characteristics of the general atmospheric circulation in February 2015 are as follows. There is one polar vortex center in the Northern Hemisphere,stronger than usual.The atmospheric circu-lation is in a four-wave pattern over mid-high latitudes.The West Pacific subtropical high is weaker than usual and the south branch trough is almost at the same position as normal.The monthly mean tempera-ture is -0.2℃,1.5℃ higher than normal.The monthly mean precipitation is 16.3 mm,which is 6.3%less than normal.Two strong cold air processes are experienced in this month,and northeast of China has one heavy snowfall process.Starting from the second half of February,more rain and snow events visit wide range of Southern China,while two haze or fog events and one sand and dust weather appear in the central and eastern part of China.
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