基于WRF模型的藏木水库局地气候影响分析

水库对局地气候的影响是水电建设项目中环境影响评价的重要方面。本文基于天气研究与预报（WRF）模型开展了区域陆面-大气耦合模拟，分析了雅鲁藏布江首座大型水电站藏木水库对周边区域地表与大气之间的水热交换及天气过程的影响。根据模拟结果，藏木水库蓄水后坝址附近降水量在冬、春、秋三季变化并不显著，夏季在低海拔河谷区域降水量有所增加。库区空气比湿增加，其中春季增幅最大；水库对东北侧下风区和上游河谷区的比湿有较为显著的影响。库区上方气温升高，冬季增温幅度最大，增幅在2 ~ 3℃；夏季增幅最小，在0.4℃左右；库周边秋冬季气温升高，夏季略有降低。研究结果可为高原水库建设的环境影响评价提供参考。

Investigating impact of Zangmu Reservoir on local climate based on WRF model

The impact of reservoir on local climate is an important aspect of environment impact assessment for a hydropower construction project, such as the Zangmu Reservoir, the first large hydropower station on the middle Yarlung Zangbo River. This paper focuses on this reservoir and its surrounding area, and conducts regional land-atmosphere coupling simulations using the Weather Research and Forecasting (WRF) model to examine its influence on regional climate factors－the water and heat exchange between the land surface and atmosphere and the weather process. For the reservoir, different numerical simulation schemes are designed for the WRF model, considering hydrological changes caused by its impoundment, and its impact on the regional microclimate is analyzed based on the simulations. The results show that in this area, precipitation has experienced little change in spring, autumn or winter, while in summer it has manifested an increasing trend since the impoundment. Air specific humidity above the reservoir is increased throughout the year, with the largest increase in spring. Meanwhile, the impoundment has caused an increase in specific humidity across the northeast downwind zone and in the upstream valley. In the impounding area, air temperature 2 meters above the ground has risen, with the smallest rise of 0.4 ℃ in summer and the largest rise of 2 - 3 ℃ in winter. In the surrounding area, temperature has risen in autumn and winter and lowered a bit in summer. The results help environment impact assessment of plateau reservoir construction.