Roger Cameron Creel , Julia Guimond, Benjamin Jones, David M Nielsen, Emily M. Bristol, Craig E. Tweedie, Pier Paul Overduin

Climate warming is causing rapid coastal change in the Arctic. Permafrost thaw subsidence, sea-level rise, and erosion each threaten the Arctic nearshore. These agents of change have received unequal attention and their compound impact remains poorly understood. Alaska's Arctic Coastal Plain (ACP) is ideal for addressing this knowledge gap due to the region’s relatively abundant observational data and importance to Indigenous communities, socioeconomics, and geopolitics. We present the first projections of 21st century ACP evolution that include subsidence, sea-level rise, and erosion. By 2100, 6-8x more land will be transformed by these compound effects than erosion alone would impact. Our findings underscore that coastal communities may need to consider a paradigm shift in how they adapt to 21st century Arctic coastal change.