气候变化对嘉陵江流域水资源量的影响分析

 嘉陵江是长江的最大支流，流域面积约16万km2。针对2050，2100年不同的气候变化情景,选取较为不利的参数组合，根据降水、气温、湿度、风速、日照等气候要素的变化，建立潜在蒸发量模型计算流域的潜在蒸发量（ET0），再根据流域内植被的蒸散发系数（Kc），计算流域的面平均蒸散发量（ETc）。并利用流域面平均降水量减去径流深得到流域的实际蒸散发量，对计算的流域面平均蒸散发量进行验证。对不同的水平年利用降水的预测成果（气候变化情景不同具有不同的降水量预测成果）及计算流域的面平均蒸散发量，根据水量平衡模型分析计算气候变化对嘉陵江流域水量的影响。结果表明：不利条件下2050年年径流将减少23.0%～27.9%；2100将减少28.2%～35.2%；2050，2100年平均年径流分别相当于目前7年一遇和12年一遇的干旱年。由此说明，气候变化对流域内的水资源量影响十分显著。 

Impact of Climate Change on Water Resources in Jialing River of Upper Yangtze River Basin

This paper investigates the impact of climate change on water resources of Jialing River catchment in upper Yangtze River basin,China.The reference potential evaporation(ET0) and crop evapotranspiration(ETc) are calculated by using the Penman-Monteith equation,multiplying a corp coefficient Kc,respectively,Annual actual evapotranspiration(AE) is computed by annual area precipitation minus annual runoff.The water balance model is calibrated.According to the future scenarios of 2050 and 2100,the model is used to calculate annual runoff.For the most disadvantage conditions,the annual runoff will decrease 23.0% to 27.9% in 2050,and it will be 28.2% to 35.2% in 2100.By extrapolation,the 2050 and 2100,annual runoffs are equivalent to about 1 in 7 year and 1 in 12.5 year drought respectively.The effects of water resources decreasing on development in the basin are described,and uncertainties of simulated results are discussed.