21世纪前中期三江源地区极端气候事件变化趋势分析

利用国家气候中心发布的IPCC SRES A1B温室气体排放情景下水平分辨率为25 km的连续气候变化模拟试验数据, 分析了三江源地区极端气候事件变化趋势.结果显示: 2001-2050年冷暖等级呈显著增高趋势, 其中以夏季变化最为明显, 冬季变化最小; 极端高温事件发生频次呈显著增多趋势, 而极端低温事件总体呈显著减少趋势; 干湿等级呈不显著增高趋势, 四季中只有冬季干湿等级呈减小趋势, 其余三季均呈升高趋势; 干燥和暴雨事件发生频次均呈显著增多趋势.地形尤其是经、 纬度和海拔对极端气候事件的变化趋势有明显的影响.

Changes in Extreme Climatic Events over the Sources of the Three Rivers in the Prometaphase 21st Century

The change trend of extreme climate events is analyzed based on the simulation data of continuous climate change under the scenario of IPCC SRES A1B, with a resolution of 25 km. It is found that: the grade of warm-cold is significantly increasing, which is most obvious in summer, and least in winter. The frequency of extreme high temperature event is also increasing, while that of extreme low temperature event is decreasing trend overall. The grade of dry-wet is increasing, but it is not so significant. Seasonally, it is decreasing in winter, and increasing in other three seasons. The frequencies of extreme drying event and the torrential rain are increasing remarkably. Terrain, especially longitude, latitude and altitude have affected apparently the change trend of extreme climatic events.