利用中国一般、基本和基准气象站近50年的观测风速资料,分析了近50年中国沿海地区夏季风速时空变化特征,检验评估了20个全球气候模式和3个区域气候模式模拟中国沿海地区夏季风速分布和变化特征的能力,预估了21世纪初期中国沿海地区夏季风速变化特征。研究发现,(1) 近50年中国沿海地区观测夏季平均风速和极大风速均呈明显减小趋势变化,这种变化特征与近50年中国登陆台风频数变化有关。(2) 全球气候模式和区域气候模式都能较好地模拟中国沿海地区夏季平均风速的分布状况,区域气候模式模拟能力略强于全球气候模式。(3) 全球和区域气候模式都不能模拟出观测到的近50年来中国沿海地区夏季平均风速呈明显的减小趋势,部分模式能模拟出近50年来中国沿海地区夏季平均风速略呈减小趋势变化。(4) 全球和区域气候模式一致预估在B1和A1B情景下,21世纪初期中国沿海地区夏季平均风速比20世纪小;全球气候模式预估A2情景下,21世纪初期中国沿海地区夏季平均风速比20世纪大。
Based on observational data sets of general, basic, and standard climate stations in the coastal regions of China from 1965 to 2004, summer wind speed changes are analyzed. Twenty global climate models and three regional climate models have been evaluated based on their capabilities to simulate summer wind speed for 20th century, and the results are used to project the summer wind speed changes in the coastal regions of China for the 21st century. The following conclusions are drawn: (1) in recent 50 years, both summer mean wind speed and maximum wind speed observed all show declining trends over the coastal regions of China. This changing feature of wind speed in China's offshore areas is related to the changing characteristics of typhoon frequency in China. (2) Both global climate models and regional climate models possess the certain capabilities to simulate the patterns of the summer mean wind speed. The capabilities of regional climate models are slightly better than that of global climate models. (3) Both global and regional climate models are unable to simulate the obvious decrement trend shown by the observed data. Only a few of them are able to simulate the slightly decrement trend of summer wind speed changes in China for the last 50 years. (4) Global and regional climate models all predict that the summer mean wind speed in coastal regions of China for the early 21st century decreases slightly for SRES B1 and A1B scenario. The projection of summer wind speed in China's offshore areas for the early 21st century is that the speed is slightly increasing for SRES A2 scenario than that for the 20th century. (5) It is worth noting that due to current restrictions on the scientific understanding, in either case of global climate models and regional climate models, there is a considerable uncertainty in the projection of the regional climate changes, especially in projection of the wind speed. The studies on the wind projections have just been in the beginning, a large number of tests need to be done in order to get more reliable conclusions.