近百年全球气温变化对长江流域旱涝灾害的影响

Impacts of Global Temperature Changes in Last Century on Drought and Flood Disasters in Yangtze River Basin

全球气温正经历着一次以变暖为主要特征的显著变化,研究其对长江流域的影响意义重大。本文通过对历史资料(1900-2000年)的分析,了解全球气温变化背景下长江流域气温、降水量及其由此带来的旱涝灾害的变化特点。结果表明,100a来,随着全球气温的上升长江流域年平均气温也出现明显增加的趋势,近10a的增温幅度更大,增温地区以长江中下游地区为主;长江流域的降水量随气温增加而增大,随气温的降低而减少;暖期降水增加加大了洪灾发生的机率,给长江流域农业生产带来不利影响,而非暖期气温下降又会使长江流域面临干旱的威胁。研究结果可为流域内洪涝灾害的预测和预防提供参考。

Global temperature has being experienced a significant change characterized as warming up. It is very important to assess the impacts of temperature changes on the Yangtze River Basin. Based on the historical data from 1900 to 2000 in the Yangtze River Basin, the impact of temperature and precipitation on droughts and floods were studied. The evidences showed that the average temperature in the Yangtze River Basin increased in the last 100 years, especially in the last ten years, as the global temperature increased. The warming up mostly happened in the mid- dle and lower of Yangtze River. The precipitation in the Yangtze River Basin increased as temperature increased and it decreased as the tempera- ture decreased. The increase of the precipitation during the warm period increased the probability of flood, while the decrease of the temperature during the cold period increased the risk of drought in the Yangtze River Basin.