Glacial isostatic adjustment reduces past and future Arctic subsea permafrost

Sea-level rise submerges terrestrial permafrost in the Arctic, turning it into subsea permafrost. Subsea permafrost underlies ~ 1.8 million km2 of Arctic continental shelf, with thicknesses in places exceeding 700 m. Sea-level variations over glacial-interglacial cycles control subsea permafrost dis...

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Bibliographic Details
Published in:Nature Communications
Main Authors: Creel, Roger C, Miesner, Frederieke, Wilkenskjeld, Stiig, Austermann, Jacqueline, Overduin, Pier Paul
Format: Article in Journal/Newspaper
Language:unknown
Published: Springer Nature 2024
Subjects:
Ice
Online Access:https://epic.awi.de/id/eprint/58836/
https://epic.awi.de/id/eprint/58836/1/Glacial%20isostatic%20adjustment%20reduces%20past%20and%20future%20Arctic%20subsea%20permafrost.pdf
https://doi.org/10.1038/s41467-024-45906-8
https://hdl.handle.net/10013/epic.8ab4ede4-dc4b-4197-a362-42ef728c84c3
Description
Summary:Sea-level rise submerges terrestrial permafrost in the Arctic, turning it into subsea permafrost. Subsea permafrost underlies ~ 1.8 million km2 of Arctic continental shelf, with thicknesses in places exceeding 700 m. Sea-level variations over glacial-interglacial cycles control subsea permafrost distribution and thickness, yet no permafrost model has accounted for glacial isostatic adjustment (GIA), which deviates local sea level from the global mean due to changes in ice and ocean loading. Here we incorporate GIA into a pan-Arctic model of subsea permafrost over the last 400,000 years. Including GIA significantly reduces present-day subsea permafrost thickness, chiefly because of hydro-isostatic effects as well as deformation related to Northern Hemisphere ice sheets. Additionally, we extend the simulation 1000 years into the future for emissions scenarios outlined in the Intergovernmental Panel on Climate Change’s sixth assessment report. We find that subsea permafrost is preserved under a low emissions scenario but mostly disappears under a high emissions scenario.