妫水河流域未来气候变化下的水文响应研究

Research on the Hydrological Responses to Future Climate Change in Guishui River Basin

通过HadCM3降尺度数据与HSPF水文模型耦合,探讨了未来气候变化情景下妫水河流域日最高、最低气温与降水量的变化情况。基于统计降尺度模型SDSM,将1961—2099年数据降尺度到各站点,生成了两种气候变化情景下的日最高气温(T max)、最低气温(T min)和降水量(P)数据。同时,构建了HSPF水文模型,分别用2005—2006年、2007—2008年数据进行了有效率定和验证,模拟了该流域在未来气候变化下的水文响应。结果表明:妫水河流域未来90 a的气温总体呈升高趋势,而降水量和地表流量呈减小趋势;高温室气体排放情景下日最高气温、最低气温、降水量和地表流量的10 a变化率分别为0.462℃、0.453℃、-0.010 mm、-0.051 m3/s,低温室气体排放情境下分别为0.263℃、0.264℃、-0.014 mm、-0.044 m3/s,流域干旱加剧的可能性进一步加大。

The hydrological responses to future climate change on the streamflow in Guishui River Basin had been evaluated quantitatively by using HadCM3 coupled with the HSPF hydrological model. The projected daily maximum, minimum air temperature and precipitation of HadCM3 under A2 and B2 scenarios first downscaled on to local meteorological stations using the SDSM. The HSPF hydrological model applied on the Guishui River basin was calibrated and validated with the observed data from 2005 to 2006 and from 2007 to 2008 respectively. The future scenarios data of each meteorological station were then used as input to the HSPF hydrological model to simulate the corresponding future hydrological responses in the ba- sin. The results predict that daily maximum and minimum air teinperature show a reasonable upward trend, while daily precipitation and streamflow generally show a downward trend in the next 90 years. The changing rate of daily maximum temperature, minimum temperature, annual precipitati- on and streamflow are 0. 462 ℃ ,0. 453℃, -0. 010 mm, -0. 051 m^3/s, and 0. 263℃ , 0. 264 ℃, -0. 014 mm and -0. 044 m^3/s）per dec- ade respectively under A2 （B2） scenarios. The results show that the drought will be intensified in the basin in the future.