西藏1971～2008年最高最低气温时空变化及分布特征

Temporal and Spatial Characteristics of Maximum,Minimum Temperature in Tibet during 1971-2008

利用西藏地区1971～2008年气象站点的气温资料,分析了西藏地区最高、最低气温的时间和空间变化特征。结果表明,近40年西藏最高、最低气温均呈明显上升趋势,其中冬季增温幅度最大,其次是春季。最低气温增温幅度明显大于最高气温,尤其是冬季最低气温增温幅度非常显著。空间变化而言,最高气温除个别站点出现降温外,大多数站点均有增温现象;而最低气温在空间上均为增温。另外,最低气温的空间变化规律比最高气温明显,基本上由东南部向中西北部地区递增,各季节呈现出不同的空间变化特征。从年代际变化看,20世纪70年代至21世纪前8年,最高气温和最低气温均呈升高趋势,最低气温增温幅度明显高于最高气温。在21世纪前8年,最高、最低气温增温幅度最高,而在20世纪70年代增幅最低。

The temporal-spatial characteristics of maximum and minimum temperature in Tibet were analyzed by using temperature data during 1971-2008.The results showed that both the maximum temperature and the minimum temperature increased,with the most increase of temperature,and more increase in spring.The minimum temperature increased significantly than the maximum temperature,what＇s more in winter.In space character,maximum temperature increased in most of stations,minimum temperature increased in all stations.The minimum temperature increased from southeast to centre west.In interdecadal variation,not only maximum temperature but also minimum temperature increased from 1970s to 8 years ago of 21century,but minimum temperature increased significantly then maximum temperature.