Melting permafrost in Alaska is releasing toxic metals into rivers, turning them orange and extremely acidic. The phenomenon is also visible from space.

The melting permafrost in Alaska has led to at least 75 rivers and streams turning orange due to the release of toxic metals. The contaminated waters are highly acidic and contain high levels of zinc, nickel, copper and cadmium, which are dangerous to aquatic life. This has serious consequences for the ecosystem and can significantly affect US fisheries.