近45年雅鲁藏布江流域极端气候事件趋势分析  

Trends in Daily Temperature and Precipitation Extremes over the Yarlung Zangbo River Basin during 1961-2005

作　　者：游庆龙[1,2] 康世昌[1,3] 闫宇平[4] 徐彦伟[1,2] 张拥军[1,2] 黄杰[1,2] 

机构地区：[1]中国科学院青藏高原研究所,北京100085 [2]中国科学院研究生院,北京100049 [3]中国科学院冰冻圈科学国家重点实验室,甘肃兰州730000 [4]国家气候中心,北京100081

出　　处：《地理学报》2009年第5期592-600,共9页Acta Geographica Sinica

基　　金：国家自然科学基金项目(40771187;40830743);国家科技部“973”项目(2005CB422004);中国科学院重要方向项目(KZCX2-YW-145);欧盟第六框架项目(FP6-036952)~~

摘　　要：利用雅鲁藏布江流域10个气象台站1961-2005年逐日最高气温、最低气温和日降水量资料,分析了该流域气温和降水等气候极端事件的变化趋势。研究表明:近45年以来,雅鲁藏布江流域夜间和白天极端低温日数分别以1.94和0.97天/10年的趋势在显著减少,夜间极端低温日数减少在冬季最明显,白天极端低温日数在秋季减少最明显;夜间极端高温日数和白天极端高温日数分别以3.03和1.26天/10年的速度显著增加,夜间极端高温日数增加在夏季最明显,白天极端高温日数增加在冬季最明显;日较差以0.11oC/10a的速度在显著减少,主要发生在冬季;最大的1天降水总量和逐年连续无降水天数有减少趋势,最大的5天降水总量、中雨天数、逐年平均降水强度和逐年连续降水天数有增加趋势,90年代以来增加趋势明显,与该地区经向风与水汽通量增加有关。Based on daily temperature （maximum and minimum） and daily precipitation at 10 meteorological stations over the Yarlung Zangbo River Basin observed by the China Meteorological Administration during the 1961-2005 period, the spatial and temporal variations in climate extremes are analyzed. The results are as follows： Over the 1961-2005 period, the regionally averaged occurrence of extreme cold days and nights has significantly decreased by-0.97 and -1.94 days/decade, respectively. Over the same period, the occurrence of extreme warm days and nights has significantly increased by 1.26 and 3.03 days/decade, respectively. The diurnal temperature range （DTR） exhibits a decreasing trend （0.11℃/decade）, especially in winter, coinciding with the fact that there is a greater rise in the minimum temperature than in the maximum temperature. The decrease in the number of cold days mostly occurs in winter and autumn, while the increase in the number of warm nights and days mainly happens in summer and winter. Precipitation indices, due to the large and expected spatial variability, indicate that regionally averaged annual maximum with 1-day precipitation and consecutive dry days have no statistically significant decreasing trends. At the same time, there is no significant increase in regionally averaged daily rainfall intensity, consecutive wet days, number of heavy precipitation days and maximum annual amount for 5-day precipitation.

关 键 词：雅鲁藏布江流域 极端气候 趋势 

分 类 号：P467[天文地球—大气科学及气象学]