CNN
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Rivers and streams in Alaska are changing color – from a clean, clear blue to a rusty orange – because of the toxic metals released by thawing permafrost, according to a new study.

The finding surprised researchers from the National Park Service, the University of California at Davis and the US Geological Survey, who conducted tests at 75 locations in the waterways of Alaska’s Brooks Range. The rivers and streams in the range appeared to rust and became cloudy and orange over the past five to 10 years, according to the study published in the journal Communications: Earth & Environment.

The discoloration…