Terrestrial vegetation plays a crucial role in governing the land surface energy budget, which in turn drives the climate of the Earth. The climatic feedbacks of vegetation changes are different across vegetation greenness gradients and climatological conditions, which has not been studied clearly. In this study, we used remote sensing and re-analysis datasets to investigate global climatic feedbacks of vegetation changes on the surface air temperature (SAT). The Common Land Model (CoLM) was also used to reproduce land-atmosphere energy processes and to explain the climatic feedbacks based on the biophysical mechanisms. Our results show that the sensitivity of SAT to the increase in vegetation greenness presents a convergent relationship. The sign and magnitude of the sensitivity are determined by the background climate conditions. The convergence sensitivity is regulated by the corresponding variations of satellite-observed evapotranspiration (ET) and albedo, and the associated partitioning of surface energy between sensible and latent heat fluxes simulated by the CoLM. The exploration of the global climatic feedbacks of vegetation changes in this work will be helpful to identify future climate change required for the development of appropriate strategies for mitigating global warming.

中文翻译：

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全球地表气温对植被绿度的敏感性

陆地植被在控制地表能量收支方面起着至关重要的作用，而这反过来又推动了地球的气候。植被变化的气候反馈因植被绿度梯度和气候条件而异，尚未得到明确研究。在这项研究中，我们使用遥感和再分析数据集来研究植被变化对地表气温 (SAT) 的全球气候反馈。共同土地模型 (CoLM) 还用于重现陆地 - 大气能量过程并解释基于生物物理机制的气候反馈。我们的结果表明 SAT 对植被绿度增加的敏感性呈现收敛关系。敏感度的符号和大小由背景气候条件决定。收敛灵敏度受卫星观测到的蒸散量 (ET) 和反照率的相应变化以及 CoLM 模拟的感热和潜热通量之间的表面能相关分配的调节。在这项工作中探索植被变化的全球气候反馈将有助于确定未来气候变化所需的制定减缓全球变暖的适当战略。