大气混合层高度的模式计算和分析

Model Computation and Analysis about Evolution of Mixed Layer Height in Atmosphere

设计了一套描述混合对流层平均状况的平板模式,模拟了混合层平均要素随时间的演变过程。采用能量学方法,通过考虑影响混合层演变的浮力、风切变及下沉等因子,对混合层高度随时间变化的过程进行数值模拟计算,并与实际观测资料比较。结果表明,模式可以较好地应用于实际业务预报中,同时改进了模式的计算方法,分析了各种物理参数对混合层高度变化的不同影响和物理成因。

A set of equations, the slab model, governing the mean state of convectivly mixed layer are firstly designed and used then to simulate the evolution of the mean elements in mixed layer with time. Using the energy method and taking the factors of buoyancy, wind shear and downdraft into account, we have calculated the process of the mixed layer height varied with time. The results show that the model can be used in operational forecast. Meanwhile the calculation method of model is improved and the effects of the physical factors on the evolution of mixed layer height are discussed.