How will permafrost carbon respond to future climate change? A new assessment for future thaw trends of permafrost carbon on the Tibetan Plateau
Tongqing Shen,
Zhongbo Yu,
Dawei Zhang,
Qin Ju,
Xuegao Chen,
Hui Lin,
Ting Nie,
Qin Wang,
Xinrong Si,
Peng Jiang
Affiliations
Tongqing Shen
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China
Zhongbo Yu
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing 210098, China
Dawei Zhang
China Institute of Water Resources and Hydropower Research, Beijing 100038, China
Qin Ju
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Nanjing 210098, China
Xuegao Chen
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China
Hui Lin
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China
Ting Nie
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China
Qin Wang
Zhejiang Development & Planning Institute, Hangzhou 310030, China
Xinrong Si
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China
Peng Jiang
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Joint International Research Laboratory of Global Change and Water Cycle, Hohai University, Nanjing 210098, China; Middle Yarlung Zangbo River Natural Resources Observation and Research Station of Tibet Autonomous Region, Chengdu 610036, China; Corresponding author at: The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China.
Permafrost degradation on the Tibetan Plateau (TP) is anticipated to result in the thaw of permafrost carbon. Existing studies have been conducted to assess the future thaw of frozen carbon on the TP, primarily focusing on the deepening of the active layer while neglecting the impact of permafrost area shrinkage. This oversight may lead to a significant underestimation of the potential thaw of frozen carbon. Our research underscores the pivotal role of permafrost area shrinkage in estimating the future thaw of frozen carbon. Our findings reveal that when the combined effects of permafrost area shrinkage and active layer deepening are considered, the thaw rates of frozen carbon in various radiative forcing scenarios are nearly four times those based on active layer deepening alone. Notably, our results demonstrate substantial thaw of frozen organic carbon in the TP permafrost area under all four future scenarios: In the low radiative forcing scenario SSP1-2.6, it is predicted that 55.4 % of the organic carbon in the permafrost area 0–10 m soils will be in a state of thaw by 2100, and more than 90 % in the high radiative forcing scenario SSP5-8.5. This substantial thaw is poised to diminish the TP's current carbon sink function significantly. Our study emphasizes that as global warming persists, frozen carbon in permafrost areas will play a more active role in global carbon cycle processes in the future. Furthermore, we stress the importance of considering permafrost area shrinkage in understanding the thaw of frozen carbon, providing valuable insights for carbon balance studies on the TP.
