Microclimate Of Coastal Zone

Coastal zone is a special and valuable space for human being. It is special because it is a transient zone between the land and the ocean; it is valuable because it is a unique place for development. Study on the dynamic characteristics of the coastal climate is expected to provide important information on the amenity of the coastal zone. It is thus useful to coastal development. Due to many reasons, the basic features of the coastal climate have not yet been systematically studied. This study is aimed to establish the framework of the coastal climate and investigate the relevant phenomena by numerical method.The fifth-generation NCAR/Penn State non-hydrostatic dynamics mesoscale model MM5 is applied to the numerical study of coastal climate. The pro-process mode in MM5 is modified to facilitate the numerical model for study of idealized problem. The characteristics of the sea breeze under different shore conditions are simulated and discussed based on the numerical results. It is shown that the development and structure of the sea land breeze depends very much on the physical conditions of the coast.Topography is an important natural property of coastal zone. Numerical studies are carried out for two cases with typical change of shoreline profile: one is the case with a bay and the other is the case with a peninsula. The main factors representing the coastal climate, including surface pressure, sea breeze and sensible heat flux, are computed. It is shown that the wind has a tendency to converge or diverge due to the existence of the bay or the peninsula. Large bay or peninsula intensifies the flexural coastline effects. The landform is simplified as an inclined surface parallel to the coastline. Main factors representing the coastal climate are computed on cases in conditions of different slope locations and different grades. Dynamic effects and thermal effects of the slope are also discussed.The effect of different land use on coastal climate is also considered. Afterwards the effects of coastal wasteland use in Jiangsu Province on climate are investigated. It is shown that, as a result of the land use and land cover change, the net radiation and evapotranspiration increased, thereby the air pressure and humidity are increased while the sea land breeze is decreased.