The thawing of the Yukon River Delta in Alaska

This false-colour image, obtained from data acquired by one of the Copernicus Sentinel-2 satellites on 15 May 2021, shows the Yukon River Delta in the US state of Alaska in the first phase of spring thaw.

The delta includes extensive wetlands that are protected in the Yukon Delta National Wildlife Refuge, the second largest wildlife refuge in the United States. The thaw in this area generally starts in the last weeks of April. In this image, the tundra, which is no longer snow-covered, is shown in tones of red, while the large blue areas show remnants of sea ice in the Bering Sea.

The Yukon Delta is vulnerable to climate change. Due to thawing permafrost and an increase in the duration of the fire season, the landscape of this region is changing rapidly, putting the biodiversity of the area at risk.

Free and open data provided by the Copernicus Sentinel-2 satellites are used to monitor the health of fragile ecosystems such as the Arctic tundra.