Drone surveys are revealing an alarming aspect of climate change: the extreme erosion of Arctic coastlines. The surveys, conducted by an international team of researchers led by the University of Edinburgh, have reported the erosion is on occasion up to a meter a day.
More than a meter a day
The team flew drone-mounted cameras over a section of permafrost coastline on Herschel Island, also known as Qikiqtaruk, off the Yukon coast in the Canadian Arctic. They further mapped the area seven times over 40 days in the summer of 2017.
Alarmingly, they found that the coast had retreated by 14.5 meters during the period, sometimes more than a meter a day. They then led a comparison with surveys dating from 1952 until 2011.
The erosion in 2017 was more than six times the long-term average for the area. This is because storms in the Canadian Arctic are washing away increasing amounts of coastal permafrost.
With warming climate leading to longer summer seasons, sea ice melts earlier and reforms later exposing the coastline to increased storm damage. "Big chunks of soil and ground break off the coastline every day, then fall into the waves and get eaten away," said Dr Isla Myers-Smith, of the University of Edinburgh's School of GeoSciences, who took part in the study.
This change is now threatening infrastructure essential to local communities such as on Qikiqtaruk - Herschel Island. It is even affecting cultural and historic sites. This is where drone surveys could come to help by providing more effective monitoring.
"As the Arctic continues to warm faster than the rest of our planet, we need to learn more about how these landscapes are changing. Using drones could help researchers and local communities improve monitoring and prediction of future changes in the region,'" said Dr Andrew Cunliffe, currently of the University of Exeter's Geography department, who led the study.
The research was carried out in collaboration with the University of Exeter, Alfred Wegener Institute, Germany, the GFZ German Research Centre for Geosciences, the Vrije Universiteit Amsterdam and Dartmouth College. It was supported by the UK Natural Environment Research Council, the National Geographic Society, and Horizon 2020.
The study was published in the journal Cryosphere.