环太湖地区土地利用变化的局地气候效应

利用WRF模式和1985年、2005年环太湖区域的土地利用资料，模拟了环太湖区域土地利用变化的局地气候效应，并从陆面过程的角度进行了分析。模拟结果显示：城市扩张区域净短波辐射通量增多，地面温度升高，感热通量增大，潜热通量减小。近地面水平风场在城市化地区风速减小，在城市化带方向上形成狭长的动能衰减区域。湖陆风和城市热岛环流增强，城市化地区向上垂直速度增大，积云性降水增多。老城区和郊区下沉运动增强，对流受到抑制，积云性降水减少。层云降水的改变，集中在层云降水的大值区，且多呈带状分布。总降水在城市化区域增强，在老城区和郊区减少，积云性降水占总降水的比值增大。在土地利用没有变化的区域，降水的改变与地表能量通量的改变在空间分布上大致吻合。

Local climate response to land use change in Taihu lake area

By using the WRF model and land use data in 1985 and 2005 in Taihu lake area two numerical simulations are conducted to study the local climate responses to land use change. An analysis from a point of view of land surface processes is also performed. The results show that net short wave radiation fluxes, ground surface temperatures, and sensitive heat fluxes increased in the urbanized areas, while latent heat fluxes decreased. A decline of wind speed was found in the urbanized areas, and in the direction of the urbanization the belts in which kinetic energy decreased were also found. Moreover, lake breeze and urban heat island circulations enhanced. Consequently, cumulus precipitation occurred in urbanized areas and increased due to the additional vertical velocity, while convection and cumulus precipitation in old town and suburbs were inhibited. Stratiform precipitation's change was limited in areas of concentrated stratiform rainfall. Total precipitation increased in urbanized area, but decreased in old town and suburbs, with the growing proportion of convective precipitation. In areas with no land use change, the pattern of precipitation change coincided quite well with the pattern of surface energy flux change.