美国伍兹霍尔海洋研究所
据介绍，随着海平面上升、永久冻土融化、风暴加剧和海冰变薄，北极海岸线容易受到气候变化的影响。75年的航空和卫星观测表明，海岸侵蚀已经成为北极受到的日益严重的危害。
然而，其他危害——例如，海平面上升和永久冻土融化沉降对永久冻土海岸线的累积影响——受到的关注较少，这使得对这些过程的影响的评估无法与海岸侵蚀相比较，也无法与海岸侵蚀相结合。阿拉斯加的北极海岸平原（ACP）是进行此类评估的理想地点，因为该地对地形、海岸退缩率和永久冻土特征有着高密度观测，及对土著社区和油田基础设施非常重要。
研究人员对21世纪北极海岸线位置进行预测，包括侵蚀、永久冻土沉降和海平面上升。以ACP为重点，研究人员将5米地形、卫星衍生的沿海湖泊深度估算、永久冻土融化导致的地面沉降的经验评估，与政府间气候变化专门委员会AR6报告中，对中、高排放情景下海岸侵蚀和海平面上升的预测结合起来。
研究发现，到2100年，侵蚀和洪水将共同改变ACP，引发比单独的海岸侵蚀多6-8倍的土地损失，并干扰多8-11倍的有机碳。如果不采取缓解措施，到2100年，沿海变化可能会破坏目前ACP沿海村庄40%至65%的基础设施，和10%至20%的油田基础设施。
研究结果强调了复合气候灾害加剧对沿海社区构成的风险，并强调了21世纪对北极海岸线进行适应性规划的必要性。
附：英文原文
Title: Permafrost thaw subsidence, sea-level rise, and erosion are transforming Alaska’s Arctic coastal zone
Author: Creel, Roger, Guimond, Julia, Jones, Benjamin M., Nielsen, David M., Bristol, Emily, Tweedie, Craig E., Overduin, Pier Paul
Issue&Volume: 2024-12-3
Abstract: 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.
DOI: 10.1073/pnas.2409411121
Source: https://www.pnas.org/doi/abs/10.1073/pnas.2409411121