Biophysical Impacts of Global Deforestation on Near-Surface Air Temperature in China: Results from Land Use Model Intercomparison Project Simulations

Global deforestation has been recognized as an important factor influencing climate change over the past century. However, uncertainties remain regarding its biophysical impacts on temperature across China. Utilizing monthly data from eight global climate models of the Land Use Model Intercomparison Project, a multimodel comparison was conducted to quantitatively analyze the biophysical impacts of global deforestation on near-surface air temperature in China, using a surface energy balance decomposition method. Results show a 38% (29% to 45%) reduction in forest cover in China (ensemble mean and range across eight models) relative to pre-industrial levels, and an annual cooling of 0.6 K (0.05 to 1.4 K) accompanied by global deforestation. Notably, surface albedo causes a cooling effect of 0.6 K (0.2 to 2.0 K), while surface latent and sensible heat fluxes partially offset this cooling by 0.2 K (-0.2 to 0.5 K) and 0.2 K (-0.04 to 0.6 K), respectively. These effects are more pronounced in winter and spring in deforested regions. Furthermore, the separation of atmospheric feedbacks under clear-sky and cloudy conditions show that the cloud radiative effect only accounts for 0.1 K (-0.1 to 0.4 K), while the clear-sky surface downward radiation is a significant cooling factor, contributing up to -0.5 K (-1.2 to 0.004 K), particularly in summer. However, the consistency of these models in simulating the impact of surface latent heat flux and albedo on surface temperature in China in response to deforestation is somewhat poor, highlighting the need to improve these related processes.