Panarctic lakes exerted a small positive feedback on early Holocene warming due to deglacial release of methane
Panarctic lakes exerted a small positive feedback on early Holocene warming due to deglacial release of methane
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DOI：
10.1038/s43247-023-00930-2
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发表时间：
2023-07
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影响因子：
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通讯作者：
L. Brosius;Walter Anthony;K. M. Treat;C. C. Jones-C.;M. Dyonisius;M. Grosse;K. M. W. Anthony;C. Treat;M. C. Jones;G. Grosse
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作者：
L. Brosius;Walter Anthony;K. M. Treat;C. C. Jones-C.;M. Dyonisius;M. Grosse;K. M. W. Anthony;C. Treat;M. C. Jones;G. Grosse
气候驱动的永久冻土融化可以将古老的碳释放到大气中，在正反馈循环中引起进一步变暖。极地冰芯数据和热岩溶湖泊中溶解甲烷的年轻放射性碳年龄对这种反馈的重要性提出了挑战，但实地研究并没有充分考虑到通过起泡从永久冻土中释放的较老的甲烷。我们综合泛北极同位素和排放数据集，得出泛北极湖泊甲烷通量的综合年龄。现代热岩溶湖泊的甲烷年龄（距今3132 ± 731年）反映了古碳的再活化作用。热岩溶湖甲烷排放量符合极地冰芯数据的限制。这里估计，冰川湖的甲烷来源更年轻，但最终更大，落后于热岩溶湖。我们的研究结果表明，泛北极湖泊甲烷释放是一个小的正反馈气候变暖，包括高达17%的总北方半球源在冰消期。
Climate-driven permafrost thaw can release ancient carbon to the atmosphere, begetting further warming in a positive feedback loop. Polar ice core data and young radiocarbon ages of dissolved methane in thermokarst lakes have challenged the importance of this feedback, but field studies did not adequately account for older methane released from permafrost through bubbling. We synthesized panarctic isotope and emissions datasets to derive integrated ages of panarctic lake methane fluxes. Methane age in modern thermokarst lakes (3132 ± 731 years before present) reflects remobilization of ancient carbon. Thermokarst-lake methane emissions fit within the constraints imposed by polar ice core data. Younger, albeit ultimately larger sources of methane from glacial lakes, estimated here, lagged those from thermokarst lakes. Our results imply that panarctic lake methane release was a small positive feedback to climate warming, comprising up to 17% of total northern hemisphere sources during the deglacial period.