摘要
利用1961~2014年春季宁夏20个气象站的降水及NCEP再分析等资料,重点分析了不同分布型El Nino事件次年宁夏春季降水的差异。结果表明：由于El Nino事件在1990年代以后主要转为中部型,宁夏春季降水对El Nino的响应也发生了变化,由之前在El Nino发生次年春季降水偏多,转为次年春季降水偏少。东部型和混合型El Nino事件次年春季,500 h Pa高度距平场上欧亚中高纬地区环流分布及700 h Pa水汽输送条件,均有利于宁夏出现降水;而中部型El Nino事件次年春季,青藏高原南侧以偏西风为主,青藏高原东南侧相对湿度较低,不利于宁夏春季出现降水。
Based on the monthly precipitation data in spring at 20 weather stations in Ningxia and reanalysis data provided by National Centers for Environmental Prediction （NCEP）from 1961 to 2014,the impacts of El Nino events with different types on the next spring precipitation in Ningxia were analyzed.The results show that the response of the next spring precipitation in Ningxia to El Nino had changed due to the El Nino event being mainly the Central Pacific type after the 1990s,and the spring precipitation patterns changed from more to less in Ningxia.The probabilities of the anomalously more precipitation and atmospheric circulations were different under the influence of different types El Nino events.Under the influence of the Eastern Pacific and Mixed types of El Nino events,the distri-bution of 500 hPa circulation,the water transport and wind field on 700 hPa over Ningxia were benefical to produce rainfall in the next spring,and would possibly induce to increase the probability of the anomalously more spring precipitation.However,under the impact of the Central Pacific type of El Nino,the westerly winds on 700 hPa predominated over southern Tibet Plateau and the relative humidi-ty on 700 hPa was less over southeastern Tibet Plateau,which would possibly induce the probability of spring precipitation decrease.
出处
《干旱气象》
2016年第2期290-296,共7页
Journal of Arid Meteorology
基金
公益性行业(气象)科研专项(GYHY201306027)
公益性行业(气象)科研重大专项(GYHY201506001)
气象关键技术集成与应用项目(CMAGJ2015M65)共同资助
关键词
不同分布型
EL
Nino
春季降水
宁夏
ElNino
different types
El Nino
spring precipitation
Ningxia
