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It is well known that soil moisture plays important roles in hydrologic and climate modeling.With an average elevation exceeding 4,000 m, Tibetan Plateau land-surface processes greatly influence the Asian Monsoon system, regional and global water and energy cycles, and the atmospheric general circulation patterns.In this study, we utilize Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) version 6.0 to simulate the climate of Tibetan Plateau for the year of 2003.The atmospheric initial and lateral boundary conditions are provided by ERA-40 reanalysis product.We run two-levels of nested grids, with the coarse grid covering the entire China at 100-km grid-increment, and the fine grid focusing on Tibetan Plateau at 25-km gridincrement.The results show that RAMS can capture the synoptic signals as well as seasonal evolutions of 2m air temperatures and precipitations, when comparing with meteorological station observations and GPCP precipitation products.The diurnal composites of simulated surface fluxes vary between seasons, and agree well with available flux-tower measurements.In addition, a suite of sensitivity experiments is conducted by increasing and decreasing initial soil moistures by 10% and 25%.It is evident that initial soil moisture conditions can have large impacts on RAMS-simulated temperatures and precipitations, especially surface fluxes, even after long integrations.Theses results demonstrate that realistic soil moisture products have the potential to improve Tibetan Plateau climate simulations.