近55a渭河流域气候变化  

Climate change characteristics in Weihe River Basin from 1960 to 2015

作　　者：冯星 郭建青[1] 孙东永[1] 曹洋 张洪波 FENG Xing;GUO Jian-qing;SUN Dong-yong;CAO Yang(Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education,Chang’an University,Xi’an 710054,Shaartxi,China)

机构地区：[1]长安大学旱区地下水文与生态效应教育部重点实验室,陕西西安710054 [2]不详

出　　处：《干旱区地理》2018年第4期718-725,共8页Arid Land Geography

基　　金：国家自然科学基金重大项目(51190093);国家自然科学基金(51379014);中央高校基本科研业务专项(310829161008)

摘　　要：利用渭河流域21个气象站点1960—2015年逐日气象资料,应用一元线性趋势分析、Penman-Monteith模型和Morlet小波分析等技术手段分别研究年、月地表湿润指数,并对其进行标准化和气温、降水以及极端干旱事件的变化趋势计算,并分析年内变化规律,以期更好的揭示渭河流域近55 a气候的变化规律。结果表明:(1)渭河流域近55 a的气温总体上在波动中呈小幅增加的趋势,其中20世纪80年代中期到90年代初期气温的增长幅度较大,为气温升高的主要时期,年均降水量和极端干旱频率呈现小幅减少的趋势,下降的主要时期集中在80年代中后期到90年代初期和21世纪初。(2)小波周期分析发现渭河流域极端干旱事件的震荡周期尺度为13~15 a和25~30 a,气温震荡周期的时间尺度为13~15 a和25~30 a,年降水量的小波振荡周期为15~17 a和25~30 a。主震荡周期的时间尺度均为25~30 a,次震荡周期的时间尺度也较为接近,为13~15 a和15~17 a,说明三者的变化规律在一定程度上有一定的相似性。(3)研究区内5个区域的气候变化特征同时存在着一定的差异性,天水—西吉流域的年均降水量和极端干旱事件发生频率的减少幅度和年均气温的增加幅度是5个区域里变化最大的,吴其—状头区域的年均降水量和极端干旱事件的减少频率和年均温度的增加频率是5个区域里变化幅度最小的,但在总体上各区域气候要素变化趋势上是保持一致的。According to the daily meteorological data of 21 stations from 1960 to 2015 in Weihe River Basin, northwest China, We used Penman-Monteith model, climate inclination rate and Morlet wavelet to study the charac- teristics of climate change in Weihe River basin. The results showed as follows ： （ 1 ） Annual temperature was in a slowly rising trend in recent 55 years, in particular, the rate of temperature rising from the middle of the 1980s to the early 1990s was faster than the rate at any other times. The annual precipitation has been slowly declined in recent 55 years. The periods from the middle of the 1980s to the early 1990s and the early 21st century were the major pre- cipitation decreased periods. （2）The results from Morlet wavelet analysis indicated a vibration period scale as 13 years to 15 years for a sub fluctuation and 25 years to 30 years for a main fluctuation about both the extreme drought events and the air temperature, a sub fluctuation of 15 years to 17 years and main fluctuation of 25 years to 30 years about the annual precipitation. It is shown that the changing rules of the three are similar. （3） There are some differences in the climate change characteristics of the research area. The minimal trend of the annual temperature and precipitation is Wuqi-Zhuangtou Basin, and the greatest change trend of annual precipitation and extreme drought events is Tianshui-Xiji Basin. In general, the change of climate elements in the research area are basically consistent.

关 键 词：渭河流域 气候特征 极端干旱事件 Penman-Monteith模型 

分 类 号：P467[天文地球—大气科学及气象学]