Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

Abstract

Citation: Liu F, Chao J P. Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution.Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.semi-analytic, global vegetation distribution, air temperature, the land surface, radiation balanceThe interaction between the atmosphere and the biosphere has aroused great interest for a long time. Since Charney [1] developed a simple land-atmosphere interaction model to study the theory of desertification, the land surface processes, especially the ecological processes, have been further noticed to develop the global or regional climate model. Some coupled ecological processes were included to develop the climate model by Dicknson [2] and Sellers [3] . Land surface related works have been flourishing in China since the 1980s. Ji [4] developed a simple land surface model for the climate research in the 1980s. A soil-vegetation-atmosphere interaction model was studied by Zhao [5] . To study the climate the Institute of Atmospheric Physics of Chinese Academy of Sciences developed a land surface model [6] .It seems that the land-atmosphere interaction is more complicated than the ocean-atmosphere interaction when the global change is focused on.Many essential features of the effect of the vegetation distribution on the atmosphere have been simulated using various versions of a general circulation model (GCM), while many fundamental questions have not been well understood. In addition to the above complicated models, our works use the theoretical model of Chao [7] , dividing the atmosphere into two layers, the upper free inertial atmosphere layer and the lower boundary layer. The lower boundary layer has no h...

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