摘要
2011年3月15日～18日,云南省玉溪市出现一次强倒春寒天气过程,平均气温除元江外,其余县仅有6.2～8.8℃;48小时最高气温下降17～23℃,通海16日最低气温只有1.8℃。分析1971～2010年历史上3月倒春寒发生前的1月大气物理特征量发现,此次倒春寒的原因主要是由于1月极涡面积偏大,3月强度迅速发展偏强,对应极圈西南侧为120～80 gpm的负距平,有利于冷空气形成;经向环流南北交换大,南支槽和东亚槽比常年偏强,有利于暖湿气流的输送,青藏高压比常年偏弱,有利于冷空气南下,造成自北向南出现较大的降温幅度,其中云南东部等地降温幅度超过12℃。
From March 15, 2011 to 18, a process of strong late spring cold happened in Yuxi. The average temperature was 6. 2℃ - 8.8℃ in most counties, except Yuanjiang. 48 hrs maximum temperature dropped 17℃ - 23℃ , the minimum temperature of Tonghai was only 1.8℃ on March 16. Analysis of the history atmospheric physical factors in January from 1971 to 2010 found the main reason which caused the late spring cold was that the polar vortex area was too large in January, and rapidly became strong in March, corresponding to the negative anomaly 120 - 80 gpm of the southwest side of polar circle, was conducive to the formation of cold air. The northsouth exchange of meridional circulation was large, the southern trough and the East Asia trough were stronger than normal, was conducive to the transport of warm air. The Tibetan high was weaker than normal, was conducive to cold air moving southward, and caused the large temperature drop range from north to south. In eastern Yunnan, the range was more than 12℃ .
出处
《云南地理环境研究》
2012年第2期73-77,共5页
Yunnan Geographic Environment Research
基金
云南省玉溪市重点科技项目"新农村气象信息服务体系建设研究及推广应用"资助
关键词
玉溪市
倒春寒
天气
环流特征
Yuxi City
late spring cold
weather
circulation features
