1965—2016年青藏高原关键气象因子变化特征及其对土地沙漠化的影响

Climate change and impact on desertification in Qinghai-Tibet Plateau from 1965-2016

选取1965—2016年青藏高原79个气象站点的年平均气温、年降水量和年均风速数据,采用趋势分析法和Mann-Kendall方法,探讨了近52a来青藏高原气温、降水、风速等关键气象因子的年际变化特征及其对沙漠化的影响.结果表明,52a来青藏高原年平均气温上升速率达0.37℃·(10a)^(-1),年降水量增速达6.95mm·(10a)^(-1),年均风速每10a显著降低0.11m·s^(-1),气候要素变化有利于土地沙漠化逆转,且气候要素变化对土地沙漠化过程的影响逐渐增强.高原不同区域年平均气温、降水量和平均风速的变化趋势基本一致,但变化幅度和突变发生时间存在差异.从东南部的"三江"流域至北部的柴达木干旱盆地,气温、降水和风速的变化幅度增大,气候变化对土地沙漠化逆转过程的影响不断增强.

Climate change is a key driving force of land desertification.Meteorological data（annual mean temperature,annual precipitation and annual mean wind speed）at 79 stations in Qinghai-Tibet Plateau from 1965-2016 were analyzed for inter-annual variation,and for influence on desertification,by trend analysis and Mann-Kendall analysis.It was found that Qinghai-Tibet Plateau sustained annual mean increase rate of 0.37℃·（10 a）^-1 in temperature,6.95 mm·（10 a）^-1 in precipitation,and a decrease rate of 0.11 m·s^-1·（10 a）^-1 in wind speed in the 52 years examined.Recent climate change showed a more favorable role to desertification reversion compared to desertification.Variation in meteorological data in sub-regions was consistent with trends in the whole plateau,but magnitude of variation and time of mutation were different.From sub-regions of the Nujiang River,Lancang River,and Yangtze River watersheds to sub-region of Qaidam Basin,variation trend of meteorological data increases which shows a gradually changed but more favorable climate to desertification reversion.