A once-sparkling Alaskan river has turned a sickly orange color » Yale Climate Connections

Transcript:

Alaska’s Salmon River was once known for its clean, sparkling water.

But recently the river has turned a sickly shade of orange, and scientists say climate change is to blame.

As temperatures rise, nearby permafrost – or long-frozen ground – is thawing.

That’s letting water and oxygen seep underground and mix with sulfide minerals, creating sulfuric acid.

That acid eats away at rocks and releases metals like aluminum, cadmium, and iron. This contaminates the river and makes it cloudy and discolored.

Sullivan: “It’s pretty upsetting to see that these areas that we have cherished and tried to protect are being severely degraded by anthropogenic climate change.”

At many points along the Salmon River, Patrick Sullivan of the University of Alaska Anchorage and his colleagues found enough of these metals to be toxic to aquatic life.

Aluminum and iron can clog fish gills, while cadmium can cause calcium deficiencies.

Sullivan says dozens of other streams in Alaska and Canada show the same signs of contamination.

So climate change and melting permafrost are polluting the once-pristine rivers of the far north.

Reporting credit: Ethan Freedman / ChavoBart Digital Media