Science Source

Extremes of summer climate trigger thousands of thermokarst landslides in a High Arctic environment

States that retrogressive thaw slumps (RTS) – landslides caused by the melt of ground ice in permafrost – have become more common in the Arctic, but the timing of this recent increase and its links to climate have not been fully established
Annually resolves RTS formation and longevity for Banks Island, Canada (70,000 km2) using the Google Earth Engine Timelapse dataset
Describes a 60-fold increase in numbers between 1984 and 2015 as more than 4000 RTS were initiated, primarily following four particularly warm summers
Finds that color change due to increased turbidity occurred in 288 lakes affected by RTS outflows and sediment accumulated in many valley floors
Modeled RTS initiation rates increased by an order of magnitude between 1906–1985 and 2006–2015, and are projected under RCP4.5 to rise to >10,000 decade−1 after 2075
These results provide additional evidence that ice-rich continuous permafrost terrain can be highly vulnerable to changing summer climate