Drone cameras have revealed erosion of up to a meter a day along a section of permafrost coastline on Qikiqtaruk, also known as Herschel Island, off the Yukon coast in the Canadian Arctic.
A research team mapped the area seven times over 40 days in summer 2017, from July 6 through August 15. They found that the frozen ground eroded by 14.5 meters during that period. Erosion sometimes reached a rate of a meter a day. Earlier surveys from 1952 through 2011 showed that the 2017 erosion rate was more than six times the area's long-term average.
Why the increase? Normally, sea ice protects the coastline from waves during much of the year. However, as the climate warms, sea ice melts earlier in the summer and reappears later in the fall. The longer it's absent, the more time storm-driven waves have to chew off chunks of the landscape. The warming climate also melts the permafrost and raises the sea level.
"As the Arctic continues to warm faster than the rest of our planet, we need to learn more about how these landscapes are changing," said researcher Andrew Cunliffe, quoted in a news release. "Using drones could help researchers and local communities improve monitoring and prediction of future changes in the region."
Cunliffe, who has a doctorate in physical geography, is a research fellow in dryland carbon dynamics at the University of Exeter in the United Kingdom. He led the study, which was published May 27 in The Cryosphere.
Study co-author Isla Myers-Smith of the University of Edinburgh's School of GeoSciences described what's happening this way: "Big chunks of soil and ground break off the coastline every day, then fall into the waves and get eaten away." This short video of drone footage shows what she's talking about.