Cosmic dust reveals dynamic shifts in central Arctic sea-ice coverage over the past 30,000 years
La poussière cosmique révèle des changements dynamiques dans la couverture de glace de mer de l'Arctique central au cours des 30 000 dernières années
Pavia, Frank J. ; Farmer, Jesse R. ; Gemery, Laura ; Cronin, Thomas M. ; Treffkorn, Jonathan ; Farley, Kenneth A.
Année de publication
2025
Arctic sea-ice loss affects biological productivity, sustenance in coastal communities, and geopolitics. Forecasting these impacts requires mechanistic understanding of how Arctic sea ice responds to climate change, but this is limited by scarce long-term records. We present continuous 30,000-year reconstructions of sea-ice coverage from the Arctic Ocean based on measurements of two isotopes, thorium-230 and extraterrestrial helium-3, whose burial ratio changes with sea-ice coverage. We found that the central Arctic was perennially covered by sea ice during the last glaciation. Sea-ice cover retreated during the deglaciation approximately 15,000 years ago, culminating in seasonal sea-ice coverage in the warm early Holocene, before ice coverage increased into the late Holocene. Sea-ice changes closely correlate with biological nutrient consumption, supporting projections of a nutrient-starved central Arctic Ocean with continued sea-ice loss.</div>
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