Increase in Arctic coastal erosion and its sensitivity to warming in the twenty-first century

Abstract

Arctic coastal erosion damages infrastructure, threatens coastal communities and releases organic carbon from permafrost. However, the magnitude, timing and sensitivity of coastal erosion increase to global warming remain unknown. Here we project the Arctic-mean erosion rate to increase and very likely exceed its historical range of variability before the end of the century in a wide range of emission scenarios. The sensitivity of erosion to warming roughly doubles, reaching 0.4–0.8 m yr−1 °C−1 and 2.3–4.2 TgC yr−1 °C−1 by the end of the century. We develop a simplified semi-empirical model to produce twenty-first-century pan-Arctic coastal erosion rate projections. Our results will inform policymakers on coastal conservation and socioeconomic planning, and organic carbon flux projections lay out the path for future work to investigate the impact of Arctic coastal erosion on the changing Arctic Ocean, its role as a global carbon sink, and the permafrost–carbon feedback.

Climate change hotspots and implications for the global subsea telecommunications network

“…Mean multi-decadal rates of 0.5-1 m/year are reported, with measured annual erosion rates peaking up at >20 m/year and a total observed coastal retreat of 50-175 m in localized areas over the last two decades, such as Drew Point in Alaska and Mamontovy Khayata in the Laptev Sea (Rolph et al, 2021). These rates indicate that the total regional Arctic coastal retreat may reach ~1 km by the end of the 2100 and may exceed several kilometres following the 50-500% projected pan-Arctic under SSP1-2.6, SSP2-4.5 and SSP5-8.5 scenarios (retreat rates of 1.5-3 m/year; Nielsen et al, 2022).…”

Shoreline change rates and land to sea sediment and soil organic carbon transfer in eastern Parry Peninsula from 1965 to 2020 (Amundsen Gulf, Canada)

“…The regional differences are explained by cliff height, ground-ice volume, and SOCC and retreat rates variability. The Laptev and East Siberian Seas contribute for three quarters of the pan-Arctic SOC losses, due to the very high erosion rates, very high ground ice content (80 %) and very high SOCC (Nielsen et al, 2022). The Beaufort Sea coast presents mean retreat rates of 1.1 m/yr and an average ground ice content of 28.5% (Overduin et al, 2014).…”

Wave propagation in the marginal ice zone: connections and feedback mechanisms within the air–ice–ocean system

“…Most Arctic coasts are eroding rapidly [76,77], and waves are a clear driver of these changes [78][79][80][81]. The presence and absence of sea ice controls the wave exposure at the coast, with strong regional variability [82].…”