Parameterization improvements and functional and structural advances in Version 4 of the Community Land Model

作者：David M. Lawrence, Keith W. Oleson, M. Flanner, Peter Thornton, Sean Swenson, Peter Lawrence, Xubin Zeng, Zong‐Liang Yang, Samuel Levis, Kôichi Sakaguchi, Gordon B. Bonan, A. G. Slater · 发表于：Journal of Advances in Modeling Earth Systems · 年份：2011 · DOI：10.1029/2011ms000045 · 被引用次数：923 · 研究领域：Land Use and Ecosystem Services、Plant Water Relations and Carbon Dynamics、Greenhouse Technology and Climate Control

The Community Land Model is the land component of the Community Climate System Model. Here, we describe a broad set of model improvements and additions that have been provided through the CLM development community to create CLM4. The model is extended with a carbon-nitrogen (CN) biogeochemical model that is prognostic with respect to vegetation, litter, and soil carbon and nitrogen states and vegetation phenology. An urban canyon model is added and a transient land cover and land use change (LCLUC) capability, including wood harvest, is introduced, enabling study of historic and future LCLUC on energy, water, momentum, carbon, and nitrogen fluxes. The hydrology scheme is modified with a revised numerical solution of the Richards equation and a revised ground evaporation parameterization that accounts for litter and within-canopy stability. The new snow model incorporates the SNow and Ice Aerosol Radiation model (SNICAR) - which includes aerosol deposition, grain-size dependent snow aging, and vertically-resolved snowpack heating – as well as new snow cover and snow burial fraction parameterizations. The thermal and hydrologic properties of organic soil are accounted for and the ground column is extended to ~50-m depth. Several other minor modifications to the land surface types dataset, grass and crop optical properties, atmospheric forcing height, roughness length and displacement height, and the disposition of snow-capped runoff are also incorporated.Taken together, these a...