陆面模式CoLM在青藏高原不同典型下垫面的应用研究

Accurate simulation of the land surface processes characteristics constitutes core of this study. However it’s often seen in practice that the models delink from the observations. Therefore, justifiable parameterization of the surface turbulent heat and soil moisture and heat transport process is vital to improve land surface simulation ability．Given the complexity of Tibetan plateau underlying surface, applicable simulation study on common land surface model (CoLM) is yet to be bettered in this region. This study is designed to acquire insight into typical underlying surfaces characteristics by means of analysis of atmosphere interaction parameters (surface albedo, momentum transfer coefficient, heat transfer coefficient, aerodynamic roughness length, thermal roughness length and excess resistance to heat transfer) and soil moisture and heat transport parameters in 7 typical underlying surfaces ( named as alpine meadow, desert steppe, high mountain forest, plateau lake, Glacier, alpine steppe and Gobi desert, respectively). Meanwhile the identified key parameters will find its application into optimization of land process simulation and improvement of parameterization schemes of CoLM. Thus applicable simulation in Tibetan Plateau will be enhanced hereafter.

陆面过程模拟研究的核心是准确地模拟陆面过程特征，但现在最大的困难是观测与建模的脱节，而提高陆面模式的模拟能力的关键在于提出准确合理的陆面过程参数化方案。由于青藏高原下垫面复杂这一特殊性，通用陆面过程模式（CoLM）在该区域的适用模拟研究还未全面完善。本研究拟分析计算得出青藏高原不同典型下垫面的地气交换参数（地表反照率、动量和热量总体输送系数、空气动力学和热力学粗糙度、热附加阻尼等）以及土壤水、热交换系数参数变化特征，深入了解青藏高原典型下垫面陆面过程特征；同时利用所确定的陆面参数对 CoLM 陆面过程模式进行优化改进，进而能够识别能显著改善陆面过程模拟的关键参数，从而改善陆面过程模式对青藏高原区域的模拟能力。