Numerical simulation of summer land surface energy budget in desert and oasis regions

In this paper, by extending MSPAS to include an efficient cloudless day atmospheric radiation transfer parameterization scheme, we have developed a two-dimensional model MLAIM, which allows physically realistic simulation of land atmosphere interactions as well as the feedback mechanisms. Using HEIFE experiment s observational data to validate the simulation results of MLAIM, we have discussed the unreasonable part in the simulation, and the necessity of the parameter calibration for the land surface model has been pointed out, and have modified parameterization schemes of soil water transfer in arid and semi-arid areas as well as atmospheric surface layer turbulence transfer. The modified model simulates well the summer land surface energy budget in desert under continuous cloudless conditions, and therefore, we have used MLAIM to study the impact of oasis on the land surface energy budget of its surrounding desert. We also have discussed the interactions among every component of land surface energy budget. Results indicate that the most important factor which induces the differences in land surface energy budget between oasis s windward desert and leeward desert is the water vapor transport from oasis to its leeward desert.