气候变化中下垫面作用的数值模拟

Numerical Simulations of the Effects of Underlying Surfaces on the Climate Change

本文利用一个三维数值模式,对下垫面在气候变化中的作用进行了数值模拟.共做了两个均一土壤下垫面试验和一个非均一土壤下垫面试验.结果表明,东半球夏季季风气候区的基本气候特征,主要是由海陆分布和大地形的影响所产生.但是,细致的气候特征却受下垫面土壤物理性质和初始湿度的很大影响.而且,通过环流系统的相互作用,除对本地区天气气候产生影响外,还会影响周围地区.非洲撒哈拉大沙漠的形成很可能是长期受到海陆分布及高原地形所造成的基本气候场作用的结果.

A three-dimensional model is used to simulate the effects of the underlying surfaces on the climate change. Two experiments with uniform and one with nonuniform underlying surfaces are carried out.The results show that the basic properties of the climate in the monsoon areas of the Eastern Hemisphere are mainly determined by the land-sea contrast and the topography. However the detailed characteristics are strongly affected by the properties and the initial moisture of the underlying surface soil, which can affect the climate not only in the same area but also in the vicinities through the interactions of the circulations. The cause of formation of the Sahara dasert is much likely the result of the longtime effect of the basic climate patterns induced by the land-sea distribution and the Tibetan Plateau topography.