【摘要】 利用青海南部地区1961~2004年气温、降水、积雪等资料,分析了初冬雪灾变化及环流特征。结果表明:青海南部地区初冬降雪量呈缓慢减少的变化趋势,平均积雪量变化与年及其它季相比,呈微弱的减少趋势,平均积雪量与气温呈反相关,而与降雪量呈正相关;影响青海南部地区初冬降雪的主要天气系统是西风带南北槽结合类、移动性高原槽类、高原低涡类、高原切变类、孟加拉湾风暴类;典型多雪(少雪)年高原及南亚与中亚地区850 hPa温度距平场配置为“南正北负”(“南负北正”)型5、00 hPa高原与东部沿海地区距平分布为“西低东高”(“西高东低”)型。更多还原

【Abstract】 The snow disaster variation and its circulation characteristics in the early winter are analyzed by use of the meteorological data of air temperature,precipitation and snow cover in the early winter over the southern Qinghai Province from 1961 to 2004.The result shows that snowfall over the southern Qinghai Province had been decreasing;the averaged snow cover had a slight decreasing trend comparing with other seasons,which was negatively correlated with air temperature,but positively correlated with snowfall.The principal synoptic systems of impacting snowfall in the early winter were the combinations of the westerly and south-to-north trough,moving plateau trough,plateau low pressure,plateau shear line,Bangladesh Bay storm;the configuration of the 850 hPa temperature anomaly field of the southern and middle Asia in the typical snow-abundant/scarce year on the plateau was "positive in the south and negative in the north",while the anomaly distribution of 500 hPa on the plateau and the eastern coastal area was "low in the west and high in the east".更多还原