中文摘要：

大气环流模型（GCMs）预测的气候变化情景，需通过降尺度处理得出区域尺度上未来气候变化的时空分布信息，才能满足气候变化对资源、环境和社会经济等影响进行评估的需要。本文简单介绍了目前降尺度模式的研究现状，重点分析了统计降尺度的优缺点及适用性，并应用太湖流域7个气象站点基准期（1961年～1990年）日最高气温和最低气温实测资料，对统计降尺度模型（SDSM）进行率定和验证，确定模型应用的预报因子变量，建立未来3个时期（2020s、2050s和2080s）的气温变化情景。结果表明，SDSM模型对于太湖流域日最高气温和最低气温的模拟效果较好，可以很好地模拟太湖流域未来的气温变化。与基准期相比，A2、B2情景下，太湖流域未来3个时期的日最高和最低气温变化情景都表现出明显的上升趋势，且随时间推移增幅明显增大；流域未来3个时期气温的季节变化较为明显，其中冬季增温最显著，秋季次之，春季和夏季变化相对较小。分析成果可为太湖流域未来气候变化情景的构建提供科学依据，以期为决策支持部门提供参考。

英文摘要：

Interest in regional climate simulation has grown due to increasing demand from the scientific community, decision makers and the general public for a realistic assessment of the regional impacts of natural climate variability and projected climate change. General circulation models （GCMs） perform reasonably well in simulating the present climate spatial scales, but perform poorly at the smaller with respect to annual or seasonal averages at large spatial and time scales relevant to regional impact analyses. Statistical downscaling techniques are generally used to bridge the spatial and temporal resolution gaps between what climate modelers are currently able to provide and the requirements of impact assessments. After analyzing advantages and disadvantages of the statistical downscaling technique and applicability, the daily maximum and minimum temperatures were downscaled from GCM grid to local area using the Statistical DownScaling Model （SDSM）. First, a statistical transfer function between the largescale predictors and the local daily temperature at 7 gauging stations was established for the 1961 - 1990 baseline period. Then, the transfer function was calibrated and validated using individual observation data. Finally, air temperature for future periods （2020s, 2050s and 2080s） was estimated using the validated transfer function from output of the HadCM3 SERS A2 and B2 at 7 gauging stations. The results show that this statistical approach is efficient for reproducing observed daily maximum and minimum temperature at each station. The difference of downscaled maximum and minimum temperature for SERS A2 and B2 between the baseline period （1961 -1990） and the future period （2010 - 2099） increases quickly. The scenarios for different months and seasons are quite different. The scenarios for maximum air temperature are markedly different in winter and summer, and the scenarios for minimum air temperature are distinct in winter and autumn. This investigation will provide scientific references f