Publications by authors named "Pier P Overduin"
Permafrost thaw subsidence, sea-level rise, and erosion are transforming Alaska's Arctic coastal zone.
Proc Natl Acad Sci U S A
December 2024
Article Synopsis
- Arctic shorelines are increasingly vulnerable to climate change due to rising sea levels, thawing permafrost, and worsening storms, leading to significant coastal erosion.
- Past observations have primarily focused on erosion, neglecting the combined effects of sea-level rise and permafrost thaw subsidence, particularly in areas like Alaska's Arctic Coastal Plain, which is essential for Indigenous communities and oil infrastructure.
- Projections indicate that by 2100, combined erosion and inundation could result in 6-8 times more land loss than erosion alone, potentially damaging 40-65% of infrastructure in coastal villages and emphasizing the urgent need for adaptive planning to address these climate hazards.
Frazil ice changes winter biogeochemical processes in the Lena River.
Commun Earth Environ
November 2024
The ice-covered period of large Arctic rivers is shortening. To what extent will this affect biogeochemical processing of nutrients? Here we reveal, with silicon isotopes (δSi), a key winter pathway for nutrients under river ice. During colder winter phases in the Lena River catchment, conditions are met for frazil ice accumulation, which creates microzones.
View Article and Find Full Text PDFSea-level rise submerges terrestrial permafrost in the Arctic, turning it into subsea permafrost. Subsea permafrost underlies ~ 1.8 million km of Arctic continental shelf, with thicknesses in places exceeding 700 m.
View Article and Find Full Text PDFMicrobial methane cycling in sediments of Arctic thermokarst lagoons.
Glob Chang Biol
May 2023
Thermokarst lagoons represent the transition state from a freshwater lacustrine to a marine environment, and receive little attention regarding their role for greenhouse gas production and release in Arctic permafrost landscapes. We studied the fate of methane (CH ) in sediments of a thermokarst lagoon in comparison to two thermokarst lakes on the Bykovsky Peninsula in northeastern Siberia through the analysis of sediment CH concentrations and isotopic signature, methane-cycling microbial taxa, sediment geochemistry, lipid biomarkers, and network analysis. We assessed how differences in geochemistry between thermokarst lakes and thermokarst lagoons, caused by the infiltration of sulfate-rich marine water, altered the microbial methane-cycling community.
View Article and Find Full Text PDFThawing submarine permafrost is a source of methane to the subsurface biosphere. Methane oxidation in submarine permafrost sediments has been proposed, but the responsible microorganisms remain uncharacterized. We analyzed archaeal communities and identified distinct anaerobic methanotrophic assemblages of marine and terrestrial origin (ANME-2a/b, ANME-2d) both in frozen and completely thawed submarine permafrost sediments.
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