摘要
利用西北地区 1 60个台站 1 950～ 2 0 0 0年春季降水量资料 ,讨论了西北 5个区域的旱涝气候特征 ,发现西北东部和北疆山前地带降水气候变化最为激烈 ,旱涝事件频繁。整个西北地区春季干旱虽较雨涝多见 ,但严重雨涝的发生多于严重干旱 ,且严重旱涝的发生自 2 0世纪 80年代以来有增加的趋势。西北各区的旱涝演变具有阶段性和群发性的特点 ,存在年代际的变化周期和 5～ 6年的准周期振荡。西北东部春季严重雨涝和严重干旱发生时 ,中高纬度大尺度环流及副热带大气环流特征迥然不同 ,且分别对赤道中东太平洋海温和北太平洋西风漂流区海温异常表现出遥响应的关系。
Monthly precipitation data of March～May in 1950～2000 from 160 meteorological stations of Northwest China are used for discussing flood and drought features of five subregions. Spring precipitation climate changes showed the most intense with more floods and droughts in region II and region IV. Frequencies of spring drought were more than those of spring flood in Northwest, but frequencies of spring serious flood were more than those of spring serious drought. And occurrences of serious flood / drought had increasing trend since the 1980s. Evolutions of drought and flood in each subregion had staged and mass feature, having interdecadal and 5～8 years quasi-periodic vibration. The atmospheric circulation characteristics of mid-high latitudes and subtropics between serious floods and droughts during spring season in eastern Northwest China were inverse each other. Serious floods and droughts during spring in eastern Northwest China displayed teleconnection with SST of equatorial middle-east Pacific and North Pacific westerly drift region, respectively.
出处
《气候与环境研究》
CSCD
2003年第1期1-8,共8页
Climatic and Environmental Research
基金
国家科技部社会公益研究专项资金项目"我国西北地区生态气候环境监测预测方法研究"资助
