Impacts of land surface darkening on frozen ground and ecosystems over the Tibetan Plateau  

作　　者：Shuchang TANG Tao WANG Dan LIU Tandong YAO Shilong PIAO 

机构地区：[1]Sino-French Institute for Earth System Science,College of Urban and Environmental Sciences,Peking University,Beijing 100101,China [2]State Key Laboratory of Tibetan Plateau Earth System,Resources and Environment,Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100101,China

出　　处：《Science China Earth Sciences》2024年第10期3213-3225,共13页中国科学（地球科学英文版）

基　　金：supported by the Second Tibetan Plateau Scientific Expedition and Research (STEP) Program (Grant No.2019QZKK0208);the National Natural Science Foundation of China (Grant Nos.41988101,42425106)。

摘　　要：Tibetan Plateau(TP) is known as the “Third Pole” of the Earth. Any changes in land surface processes on the TP can have an unneglectable impact on regional and global climate. With the warming and wetting climate, the land surface of the TP saw a darkening trend featured by decreasing surface albedo over the past decades, primarily due to the melting of glaciers, snow,and greening vegetation. Recent studies have investigated the effects of the TP land surface darkening on the field of climate, but these assessments only address one aspect of the feedback loop. How do these darkening-induced climate changes affect the frozen ground and ecosystems on the TP? In this study, we investigated the impact of TP land surface darkening on regional frozen ground and ecosystems using the state-of-the-art land surface model ORCHIDEE-MICT. Our model results show that darkening-induced climate changes on the TP will lead to a reduction in the area of regional frozen ground by 1.1×10~4±0.019×10~4km~2, a deepening of the regional permafrost active layer by 0.06±0.0004 m, and a decrease in the maximum freezing depth of regional seasonal frozen ground by 0.06±0.0016 m compared to the scenario without TP land surface darkening.Furthermore, the darkening-induced climate change on the TP will result in an increase in the regional leaf area index and an enhancement in the regional gross primary productivity, ultimately leading to an increase in regional terrestrial carbon stock by0.81±0.001 PgC. This study addresses the remaining piece of the puzzle in the feedback loop of TP land surface darkening, and improves our understanding of interactions across multiple spheres on the TP. The exacerbated regional permafrost degradation and increasing regional terrestrial carbon stock induced by TP land surface darkening should be considered in the development of national ecological security barrier.

关 键 词：Tibetan Plateau ALBEDO Land surface darkening Frozen ground ECOSYSTEM 

分 类 号：P467[天文地球—大气科学及气象学] P642.14[环境科学与工程—环境科学] X171.1