三门峡市冬季严重干旱成因分析
2017-07-13魏璐璐
魏璐璐



摘要 以2008年12月—2009年2月三门峡市发生的严重冬旱为例,利用1958—2016年三门峡站的常规观测资料和非常规资料,通过对单站历史资料和大气环流特征分析,初步总结出该地区冬季严重干旱的成因。结果表明,前一年夏季和秋季降水持续偏少、气温持续偏高,是导致冬季严重干旱的诱因;冬季前期(12月—次年1月)长时间持续无降水时,一般对应冬季将要出现严重干旱;西太平洋副高减弱,西风带少低槽活动,是导致三门峡市严重干旱的直接原因。
关键词 冬季干旱;环流特征;成因;三门峡市
中图分类号 S423 文献标识码 A 文章编号 0517-6611(2017)13-0172-02
Analysis on the Causes of Serious Drought in Winter in Sanmenxia City
WEI Lu-lu
(Sanmenxia City Meteorological Bureau, Sanmenxia,Henan 472000)
Abstract Taking the severe drought in Sanmenxia City from December 2008 to February 2009 as an example,using the conventional observation data and unconventional data of Sanmenxia station from 1958 to 2016,the causes of severe drought in winter were summarized by analyzing the historical data of single station and atmospheric circulation characteristics.The results showed that the precipitation in the summer and autumn of the previous year was low and the temperature was high, which was the cause of severe drought in winter.Early winter (December-January of the following year) for a long time without precipitation, the general corresponding to the winter would be a serious drought.The western Pacific subtropical high was weakened and the westerly belt with low trough activity was less,which was the direct cause of severe drought in Sanmenxia City.
Key words Drought in winter;Circulation characteristics;Cause;Sanmenxia City
干旱是我國最常见、影响最大的气候灾害,全国各地均可能发生,全国每年平均受旱面积约0.2亿hm2[1]。近几年,随着全球变暖,我国干旱灾害更加严重。三门峡市地处中纬度内陆区,受季风气候影响,一年四季分明,冬季气候特点是干冷少雨。三门峡市年降水主要集中在5—10月份,冬季(12月—次年2月)降水稀少,仅占全年降水的3%,易出现干旱。另外,由于三门峡市地处豫西山区,地形复杂,几乎每年都有不同程度的干旱发生,同时又由于雨量时空分布极不均匀,导致各地域干旱程度不同。2008年12月—2009年2月三门峡市遭遇严重干旱,部分地区降水量的偏少程度已接近或突破历史极值,特大干旱给该市农业生产和居民生活造成了严重影响。笔者以此次严重冬旱为例,利用1958—2016年三门峡站的常规观测资料和非常规资料,通过对单站历史资料和大气环流特征分析,初步总结出该地区冬季严重干旱的成因。……
