Pronounced methane cycling in northern lakes coincided with a rapid rise in atmospheric CH <sub>4</sub> during the last deglacial warming
Atmospheric methane concentration (AMC) surged by ~50% during the last deglaciation, with northern (>30°N) sources accounting for ~40% of the rise. However, hypothesized sources including expanding lakes, peatlands, and destabilized permafrost or hydrates fail to explain this rapid increase. We use biomarkers, isotopes, and radiocarbon data to reconstruct temperature change, methane cycling, and permafrost thaw from a Tibetan thermokarst lake. Radiocarbon evidence and ultradepleted δ<sup>13</sup>C values (-80.3 per mil) of methane-diagnostic lipids indicate intense cycling of ancient (~2500-year-old) methane during the Younger Dryas-Preboreal transition, coeval with the AMC surge and the most rapid warming. By contrast, methane cycling was weak during the Holocene Climatic Optimum despite peak temperatures. These findings imply that anomalously high rates of warming, rather than absolute temperature alone, may play an important role in triggering enhanced paleo-methane cycling. Rapid warming likely intensified emissions from existing northern lakes, fueling the elusive yet clearly amplified northern methane source that contributed to the deglacial abrupt rise in AMC.
Authors
- Wengang Kang (ORCID: https://orcid.org/0000-0003-2640-2019)
- Henry Holmstrand (ORCID: https://orcid.org/0000-0002-5724-8256)
- Fahu Chen (ORCID: https://orcid.org/0000-0002-8874-1035)
- Xianyu Huang (ORCID: https://orcid.org/0000-0001-6175-9158)
- Xinwei Yan (ORCID: https://orcid.org/0000-0003-3413-6048)
- Örjan Gustafsson (ORCID: https://orcid.org/0000-0002-1922-0527)
- Aifeng Zhou
- Junjie Wu (ORCID: https://orcid.org/0000-0001-7618-6989)
- Kathleen M. Rühland (ORCID: https://orcid.org/0000-0003-3994-3666)
- Jianbao Liu (ORCID: https://orcid.org/0000-0001-7970-5449)
- John P. Smol (ORCID: https://orcid.org/0000-0002-2499-6696)
- Haoran Dong (ORCID: https://orcid.org/0000-0002-8847-4002)
- J. L. Zhang (ORCID: https://orcid.org/0000-0001-5840-4479)
- Zhitong Chen (ORCID: https://orcid.org/0000-0002-9142-281X)
- Lin Chen (ORCID: https://orcid.org/0000-0001-6325-6677)
Institutions
- Tibet University (CN)
- Stockholm University (SE)
- Chinese Academy of Sciences (CN)
- Peking University (CN)
- Queen's University (CA)
- China University of Geosciences (CN)
- Central China Normal University (CN)
- Institute of Tibetan Plateau Research (CN)
- Bolin Centre for Climate Research (SE)
- Lanzhou University (CN)
Publication Details
- Journal
- Science Advances
- Published
- 2025-07-16
- DOI
- https://doi.org/10.1126/sciadv.adt2561
- Citations
- 4
- Primary Topic
- Geology and Paleoclimatology Research
- Type
- article
- Field-Weighted Citation Impact
- 5.20