Pollen-Based Holocene Thawing-History of Permafrost in Northern Asia and Its Potential Impacts on Climate Change

Frontiers in Ecology and Evolution

Natalia Rudaya¹  Fang Tian²  Xianyong Cao³  Ulrike Herzschuh⁴  Wenjia Li⁸ 

[1] Biological Institute, Tomsk State University, Tomsk, Russia;College of Resource Environment and Tourism, Capital Normal University, Beijing, China;Group of Alpine Paleoecology and Human Adaptation (ALPHA), State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China;Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany;Institute of Environmental Science and Geography, University of Potsdam, Potsdam, Germany;PaleoData Lab, Institute of Archaeology and Ethnography SB RAS, Novosibirsk, Russia;Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany;University of Chinese Academy of Science, Beijing, China;

关键词: pollen;    Random Forest;    Siberia;    East Asian summer monsoon;    permafrost;   

DOI  :  10.3389/fevo.2022.894471

来源: DOAJ

【 摘 要 】

As the recent permafrost thawing of northern Asia proceeds due to anthropogenic climate change, precise and detailed palaeoecological records from past warm periods are essential to anticipate the extent of future permafrost variations. Here, based on the modern relationship between permafrost and vegetation (represented by pollen assemblages), we trained a Random Forest model using pollen and permafrost data and verified its reliability to reconstruct the history of permafrost in northern Asia during the Holocene. An early Holocene (12–8 cal ka BP) strong thawing trend, a middle-to-late Holocene (8–2 cal ka BP) relatively slow thawing trend, and a late Holocene freezing trend of permafrost in northern Asia are consistent with climatic proxies such as summer solar radiation and Northern Hemisphere temperature. The extensive distribution of permafrost in northern Asia inhibited the spread of evergreen coniferous trees during the early Holocene warming and might have decelerated the enhancement of the East Asian summer monsoon (EASM) by altering hydrological processes and albedo. Based on these findings, we suggest that studies of the EASM should consider more the state of permafrost and vegetation in northern Asia, which are often overlooked and may have a profound impact on climate change in this region.

【 授权许可】

Unknown