不同下垫面水分与能量传输模式

A Modified SiB to Simulate Momentum, Heat and Water Transfer over Various Underlying Surfaces

首先从简单生物圈模式（ Ｓｉｍ ｐｌｅ Ｂｉｏｓｐｈｅｒｅ Ｍｏｄｅｌ） 的物理模型出发，对其控制方程进行了修改。土壤温度使用求解热传导方程得到，土壤湿度使用了水汽扩散方程、 Ｄａｒｃｙ 的水流方程同时求解得到，目的是使简单生物圈模式既能在有植被下垫面使用，又能扩展到考虑水汽运动的沙漠地区使用。为了检验修改后的模式能适用于计算不同下垫面的地气之间水分和能量交换，选择了草原、森林和沙漠三种类型，在４ 个不同的实验点得到的资料，进行了单点模式（ Ｏ Ｆ Ｆ Ｌ Ｉ Ｎ Ｅ） 检验。结果表明，修改后的简单生物圈模式模式可使用于不同下垫面地气之间水分和能量交换，尤其是解决了沙漠地区水热传输的模拟问题。

Based on the Simple Biosphere Model (SiB), a Modified SiB model (MSiB) is developed to simulate momentum, heat and water fluxes over different underlying surfaces such as grassland, forest and desert. Instead of using Force-Restore method, the heat conductive equation is used in the MSiB model to get soil temperatures at different depths. Since the MSiB model is aimed to be used not only over the vegetated surfaces but also over deserts where water vapor movement dominants, the water vapor diffusion equation and Darcy′s water flow equation are used simultaneously. By using the data observed in HEIFE and Shapotou desert, this scheme is proved to perform well in simulating water and heat flux transfer in the deserts. In order to examine its ability to simulate water and energy exchange between vegetated surfaces and the atmosphere after modification, two off-line experiments are made by using observed data in Cabauw grassland and Amazon forest. The good agreement achieves between the simulated and observed results.