Arctic warming is turning Alaska’s rivers red with toxic runoff

A yearly checkup on the region documents rusting rivers, threatening salmon

- ERIC NIILER

RECORD-SETTING TEMPERATURES and rainfall in the Arctic over the past year sped up the melting of permafrost and washed toxic minerals into more than 200 rivers across northern Alaska, threatening vital salmon runs, according to a report card issued by federal scientists.

The report, compiled by dozens of academic and government scientists and coordinated by the National Oceanic and Atmospheric Administration, documented rapid environmental changes stretching from Norway’s Svalbard Island to the Greenland ice sheet and the tundra of northern Canada and Alaska. Together, the findings underscore how quickly warming trends are reshaping the Arctic’s physical and ecological systems.