EGU22-12622
https://doi.org/10.5194/egusphere-egu22-12622
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Groundwater discharge as a driver of methane emissions from Arctic lakes

Carolina Olid1,2,3, Valentí Rodellas4, Gerard Rocher-Ros1, Jordi Garcia-Orellana4,5, Marc Diego-Feliu4,5, Aaron Alorda-Kleinglass4, David Bastviken5, and Jan Karlsson1
Carolina Olid et al.
  • 1Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå, Sweden.
  • 2Department of Forest and Management, Swedish University of Agricultural Science, Umeå, Sweden.
  • 3Department of Earth and Ocean Dynamics, Universitat de Barcelona, Barcelona, Spain
  • 4Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain.
  • 5Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain.

Methane (CH4) emissions from Arctic lakes are significant and highly sensitive to global warming. Groundwater inputs to lakes could be substantial and constitute a link between CH4 from melting permafrost to emissions via lakes. Yet, groundwater CH4 inputs and associated drivers are hitherto poorly understood. In this study, we disclose temporal and spatial patterns of groundwater CH4 inputs to Arctic lakes in the discontinuous permafrost zone in northern Sweden. Results show that groundwater discharge is a major source of CH4 to the lakes. Spatial patterns across lakes suggest that groundwater inflow rates are primarily related to lake morphology and land cover. Groundwater CH4 inputs and atmospheric CH4 emissions from lakes were higher in summer than in autumn, reflecting changes in hydrological and biological drivers. This study reveals the large role and the drivers of groundwater discharge in lake CH4 cycling, which may be further exacerbated with the ongoing climate change, as rising temperatures, increasing precipitation, and permafrost thawing are likely to increase groundwater CH4 inputs to lakes.

How to cite: Olid, C., Rodellas, V., Rocher-Ros, G., Garcia-Orellana, J., Diego-Feliu, M., Alorda-Kleinglass, A., Bastviken, D., and Karlsson, J.: Groundwater discharge as a driver of methane emissions from Arctic lakes, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12622, https://doi.org/10.5194/egusphere-egu22-12622, 2022.

Comments on the display material

to access the discussion