For several years, Alaska’s rivers have been turning orange due to toxic metals released by thawing permafrost.
he rivers and streams of Alaska change color. According to a study published on May 20 in the journal Communications: Earth & Environment, spotted by CNN, toxic metals released by melting permafrost give them an orange color. Permafrost corresponds to the portion of the ground that has remained at a temperature below 0°C for more than two years.
Researchers from the National Park Service, University of California, Davis, and the U.S. Geological Survey found that rivers in the Brooks Range have turned turbid and orange over the past five to 10 years. An appearance caused by metals such as iron, zinc, copper, nickel and lead, some of which are toxic to river and stream ecosystems, according to researchers.
A surprising phenomenon in this area of the globe
“We’re used to seeing this phenomenon in parts of California and Appalachia, where there’s a mining past,” said Brett Poulin, study co-author and professor of environmental toxicology at the University of California. Davis. “But it is very surprising to see it when you are in the most remote wilderness areas, far from a source of mining,” he added.
According to the study, Arctic soils naturally contain organic carbon, nutrients and metals, such as mercury, in their permafrost. The latter, melting due to high temperatures, mixes with the water sources surrounding them. “It’s really an unexpected consequence of climate change,” commented Brett Poulin. According to several studies, the Arctic is warming four times faster than the rest of the world. This color change is also believed to be linked to a “dramatic decline” in aquatic life, raising concerns about the communities that rely on these waterways for drinking and food.
