Identifying Arctic communities at risk from permafrost thaw by satellite
Nowhere on Earth is global warming more obvious than in the Arctic. As the region warms, its ground temperatures increase and its permafrost – a permanently frozen layer of soil, sand or rock held together by ice – thaws. This destabilises the ground and affects buildings, roads, railways and other infrastructure. So how are these changes affecting the more than three million people living in the Arctic’s permafrost regions? A study supported in part by the EU-funded Nunataryuk project has now identified the Arctic communities and infrastructure expected to be at risk as a result of permafrost thaw over the next three decades. This new insight has been made possible thanks to data from the Copernicus Sentinel-1 and Sentinel-2 satellites, combined with machine learning. The results have been published in the journal ‘Environmental Research Letters’.
More human impact, more thaw
According to the study, the Arctic coastal land area affected by human presence has increased by at least 180 km2, or 15 %, since 2000. Most of this change has occurred in Russia, followed by Canada and the United States, and can mainly be attributed to oil and gas industry activities (31 %). “These findings highlight continued industrial development, which also shows up in night-time lights observations,” the authors report in the study. A much smaller percentage (5 %) of impacted land area is associated with mining. The researchers’ findings paint a dire picture of what to expect if permafrost warming continues at the pace of the last two decades. “We used Climate Change Initiative permafrost ground-temperature trends going back to 1997 and extrapolated them to 2050, allowing us to predict where the temperature of the ground, down to a depth of two metres, will be over 0°C by 2050,” observes study lead author Dr Annett Bartsch in a news item posted on the European Space Agency (ESA) website. Dr Bartsch is the founder and managing director of Nunataryuk project partner b.geos GmbH, Austria, and the scientific leader of ESA’s Permafrost Climate Change Initiative project. “We see that 55% of the infrastructure currently located on permafrost and within 100 km of the Arctic coastline – infrastructure on which communities rely – is likely to be affected.” Dr Bartsch goes on to describe what followed the extrapolation: “We then used high-resolution data from the Copernicus Sentinel-1 mission, which carries an advanced radar instrument, and data from the Copernicus Sentinel-2 mission, which carries a camera-like instrument, along with artificial intelligence to identify communities and assets that are vulnerable to thawing permafrost.” The Sentinel-1 satellite provides all-weather, day and night radar imagery for land and ocean services, while Sentinel-2 provides high-resolution optical imagery of vegetation, soil and water cover, inland waterways and coastal areas. The study’s results highlight the importance of gaining a clearer understanding of where and to what extent permafrost thaw in the Arctic may threaten communities and infrastructure. The 6-year Nunataryuk (Permafrost thaw and the changing arctic coast: science for socio-economic adaptation) project ends in October 2023. For more information, please see: Nunataryuk project website
Keywords
Nunataryuk, Arctic, permafrost, Sentinel, infrastructure, thaw, global warming, coastal area