植被退化对青藏高原冬夏季气候影响的模拟研究

利用区域气候模式RegCM3,模拟分析了青藏高原地区植被退化对自身及周边地区气候产生的影响。结果表明：植被退化后,在退化区域冬夏季地表温度明显升高,最大增值2℃,而外围则温度降低,量值为-0.5℃～-1℃。夏季气温的变化趋势与地表温度类似,但量值较小,冬季退化区气温增加范围较大。夏季退化区湿度和降水增大,增加值分别达到0.6g/kg和35mm/month;退化区外围降水减少,外围西部及北部地区湿度减小,中心值为-0.4 g/kg。在冬季,湿度稍有减小,主要分布在西藏地区和青海、四川的交界处。

Simulation of Effect of Vegetation Degradation on Summer and Winter Climate over Tibetan Plateau

We employed the ICTP Regional Climate Model RegCM3 to simulate the impact of vegetation degradation on climate change in Tibetan plateau.The results show that：（1） There is a considerable surface temperature increase with maximum value of 2℃ in vegetation degradation region for both summer and winter.However,the surface temperature is decreased in surrounding region with value of-0.5℃~-1℃.It is worth note that the influence area range for winter is a little bit smaller than that of summer.（2） The humidity change is totally different for summer and winter.For summer,the averaged humidity increases in the degradation region with maximum value of 0.6g/kg,while decreases at north and west with value of-0.4 g/kg.On the other hand,the winter averaged humidity decreases for entire region with maximum value of-0.12g/kg.（3） The summer precipitation increases for most of the degradation region with maximum value of 35mm/month,and the comparable precipitation decrease is observed at the surrounding region.However,the winter precipitation remains almost the same as control results at degradation region,but decreases 15mm/month at south east of Tibetan plateau and middle of Sichuan,and increase 10mm/month at boundary of Tibet,Yunnan and Sichuan.