澜沧江-湄公河流域温度和降水变化趋势分析

Variation trends of temperature and precipitation in Lancang-Mekong River Basin during 1980—2009

利用澜沧江-湄公河流域7个代表气象站1980—2009年的温度和降水观测资料,采用线性倾向估计、滑动平均和Mann-Kendall检验方法对流域年、季温度和降水变化趋势进行分析。结果表明:流域年平均温度呈明显上升趋势,线性倾向率为0.02℃/a;流域北部高海拔地区温度增加趋势比南部明显,而温度季节增加趋势不明显。流域年平均降水呈增加趋势,线性倾向率为10.49mm/a,不同地区降水增减趋势不同;雨季降水增加趋势明显,而旱季降水增加趋势不明显。

Based on the observed daily temperature and precipitation of 7 representative meteorological stations from 1980 to 2009, annual and seasonal variation trends of temperature and precipitation in the Lancang-Mekong River basin were analyzed by using statistical methods of linear trend, moving average and Mann-Kendall test. The results show that annual mean temperature variation presents a fluctuating upward trend at a trend ratio of 0.01~C/a. Temperature increased more significantly in northern region of high allva- tion than in southern region of plain, while the increase in seasonal temperature is not obvious. The annu- M mean precipitation took on an increasing trend at a trend rates of 10.49mm/a. The increase in precipitation is remarkable in wet season, while it is nnt nhvimJs in dry season.