1960～2010年四川最高、最低气温的非对称性变化特征

Asymmetrical Change of Maximum Temperature and Minimum Temperature in Sichuan from 1960 to 2010

本文利用四川138个气象站点1960～2010年的气温资料,分析了四川地区年均最高、最低气温及日较差的时空变化特征。结果表明:1960～2010年四川年均最高、最低气温在时间变化上呈非对称性升温,年均最高气温和最低气温的气候倾向率分别为0.131℃/10a和0.185℃/10a,后者增温幅度约为前者的1.4倍。年均最高、最低气温气候倾向率在空间分布上多数地区也呈非对称现象,年均最高、最低气温在西部高原地区升温较快,但最低气温的升温速率明显高于最高气温,这导致气温日较差在高原西部地区下降幅度较大。年均最高气温在1980年代最低,2000年代达到最高;年均最低气温在1960年代最低,2000年代最高;年均气温日较差在1960年代最大,1980年代最小。年均最高、最低气温分别在1996年和1993年发生转变,年均气温日较差分别在1973年和2005年发生了转变,年均最高、最低气温气候倾向率的不同及转变年的不一致导致气温日较差在转变年上的不一致。

The spatial and temporal change of maximum and minimum temperatures and diurnal temperature range were analyzed based on the temperature data of 138 meteorological stations in Sichuan province from 1960 to 2010. The results showed that annual average maximum and minimum temperatures increased non - symmetrically, the maximum and minimum temperatures changed at the rate of 0.131 ~C/10a and 0. 185 ~C/10a. Annual average maximum and minimum temperatures also changed asymmetric in majority area. The maximum and minimum temperatures increased quickly in the plateau of western Si- ehuan, but the rising rate of minimum temperature was significantly higher than that of maximum temperature, which resulted to diurnal temperature range reducing obviously in the west of plateau. The lowest annual average maximum temperature was in 1980s and the highest was in 2000s. The lowest annual average minimum temperature was in 1960s and the highest was in 2000s. The highest diurnal temperature range was in 1960s, and the lowest was in 1980s. Annual average maximum and mini- mum temperatures changed abruptly in 1996 and 1993 respectively. Annual average diurnal temperature range changed abruptly in 1973 and 2005. The climate trend rate and abrupt change of average annual maximum and minimum temperatures were dif- ferent, which leaded to abrupt change of the diurnal temperature change was inconsistent.