渭河流域60年来气温变化特征与区域差异

Air temperature variation of Weihe river basin in recent 60 years and its regional differences

对渭河流域及其周边45个气象站点近60年的气温特征值,做空间插值、线性回归分析、气温突变分析和趋势分析。结果表明:1)1951～2009年间渭河流域年平均气温、年平均最低气温均呈显著上升趋势,年平均气温和年平均最低气温的的增温速率分别为0.252℃/10a和0.261℃/10a,年平均气温大于9℃区域所占流域总面积比,60年间上升34.78%;年平均最低气温大于3℃区域所占流域总面积比,60年间上升17.2%;2)年平均最高气温除1980s下降外,其余年代呈现上升趋势,增温速率为0.255℃/10a,其大于16℃区域所占流域总面积比,首先从1950s的46.27%下降至1980s的37.15%,而后又上升至2000年后的81.63%;3)年均温、年平均最低温和年平均最高温变化的转折点在1990年前后;4)气温日较差从1950s至1970s呈下降趋势,进入1980s后略有上升,其中气温日较差大于11℃区域所占流域总面积比,首先从1950s的55.96%下降至1980s的41.58%,而后又上升至2000年后的61.07%。

Based on the atmospheric temperature data of 45 stations in and around Wei River basin during 1951 2009, spatial interpolation, linear regressive analysis and climatic mutation analysis were applied, to analyze the climate trend and so on. Results showed that ： （ 1 ） The annual mean temperature and the minimum temperature of the basin showed a increasing trend, rising at the rates of 0. 252°C/10a and 0. 261°C/10a respectively. The proportion of the area where the average annual temperature was more than 9 increased by 34.78% and where the average annual temperature was more than 9 increased by 34.78% from 1951 to 2009. （2） Apart from the 1980s, the average annual maximum temperatures have been in an ascending trend, rising at the rates of 0. 255℃/10a. The proportion of the area where the average annual maximum temperatures were more than 16℃ decreased from 46.27% in 1950s to 37.15% in 1980s, then increased to 81.63% after 2000. （3） The turning points among the average annual temperature, the average minimum temperature and the average annual maximum temperature located around 1990. （4） Average diurnal range in temperature had a decreasing trend from 1950s to 1970s and the warming trends started in the 1980s. The proportion of the area where average diurnal range in temperature was more than 11 ℃ decreased from 55.96% in 1950s to 41.58% in 1980s, then increased to 61.07% after 2000.