三门峡市冬季严重干旱成因分析

摘要

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.%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.