Numerical simulation study on regional climate effect over Oasis area

By extending Modified Soil-Plant-Atmosphere Scheme (MSPAS) to include an effective parameterization scheme of atmospheric radiation transfer, a two-dimensional model was built, which allows physically realistic simulation of modified land atmosphere interactions model (MLAIM) and relevant feedback mechanisms. After modification of parameterization schemes of soil water transfer, atmospheric surface layer turbulence transfer, and vegetation processes, the simulation results were validated by using observational data in HEIFE experiment. Results indicate that the modified MLAIM can simulate well physical processes in land atmosphere interactions. As a result, MLAIM can be used as an effective method to simulate land surface energy budget in oasis and desert, and to study the regional climate effect of oasis. The authors discussed the causes of oasis 'cold island effect' and 'wet island effect', and focused on oasis's influence on its surrounding desert. Results indicate that the water vapor transport from oasis to desert serves as the most important factor which affects the land surface energy budget in desert as well as the regional climate in oasis's surrounding areas.