A 2022 drone image of the Yukon River and its floodplain downstream from Beaver, Alaska, shows accumulations of sediments, which harbor the toxic metal mercury. (Photo: Michael P. Lamb.)

‘Mercury bomb’ threatens millions as Arctic temperatures rise

With Arctic permafrost melting at a record pace, vast stores of toxic mercury put the food chain — and communities that depend on it — in grave danger. USC Dornsife scientists find a better way to assess the hazard.

ByDarrin S. Joy August 29, 2024

The Yukon River flows west across Alaska toward the Bering Sea, eroding Arctic permafrost along its banks and transporting sediment downstream. Within that sediment lurks a toxic stowaway: mercury.On a gold background, “Asgmt Earth” appears inside a black circle and “USC” inside a small, white circle that slightly overlaps the black circle.

As the Arctic warms with climate change, heating up to four times faster than the global average, mercury sequestered in the permafrost for millennia is being eroded by rivers and released into the environment.

In a study published today, researchers at the USC Dornsife College of Letters, Arts and Sciences introduce a more accurate method to measure the amount of mercury released from permafrost by the river and estimate the total mercury awaiting release.