Permafrost thaw subsidence, sea-level rise, and erosion are transforming Alaska's Arctic coastal zone

• 成果类型: Article
• 署名作者: Creel, Roger; Guimond, Julia; Jones, Benjamin M.; Nielsen, David M.; Bristol, Emily; Tweedie, Craig E.; Overduin, Pier Paul
• 署名单位: Woods Hole Oceanographic Institution; Woods Hole Oceanographic Institution; University of Alaska System; University of Alaska Fairbanks; Max Planck Society; University of Hamburg; University of Texas System; University of Texas Austin; University of Texas System; University of Texas El Paso; University of Texas System; University of Texas El Paso; University of Texas System; University of Texas El Paso; Helmholtz Association; Alfred Wegener Institute, Helmholtz Centre for Polar & Marine Research
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8545
• DOI: 10.1073/pnas.2409411121
• 发表日期: 2024-12-10
• 关键词: north slope; ground ice; acidification; exposure; driven; carbon; shelf; water

摘要

Arctic shorelines are vulnerable to climate change impacts as sea level rises, permafrost thaws, storms intensify, and sea ice thins. Seventy-five years of aerial and satellite observations have established coastal erosion as an increasing Arctic hazard. However, other hazards at play-for instance, the cumulative impact that sea-level rise and permafrost thaw subsidence will have on permafrost shorelines-have received less attention, preventing assessments of these processes' impacts compared to and combined with coastal erosion. Alaska's Arctic Coastal Plain (ACP) is ideal for such assessments because of the high-density observations of topography, coastal retreat rates, and permafrost characteristics, and importance to Indigenous communities and oilfield infrastructure. Here, we produce 21st-century projections of Arctic shoreline position that include erosion, permafrost subsidence, and sea-level rise. Focusing on the ACP, we merge 5 m topography, satellite-derived coastal lake depth estimates, and empirical assessments of land subsidence due to permafrost thaw with projections of coastal erosion and sea-level rise for medium and high emissions scenarios from the Intergovernmental Panel on Climate Change's AR6 Report. We find that by 2100, erosion and inundation will together transform the ACP, leading to 6-8x more land loss than coastal erosion alone and disturbing 8-11x more organic carbon. Without mitigating measures, by 2100, coastal change could damage 40 to 65% of infrastructure in present-day ACP coastal villages and 10 to 20% of oilfield infrastructure. Our findings highlight the risks that compounding climate hazards pose to coastal communities and underscore the need for adaptive planning for Arctic coastlines in the 21st century.