Mercury from thawing permafrost: A new climate change tipping point
Kevin Schaefer
National Snow and Ice Data Center
University of Colorado Boulder
Nov 12, 2021
GUGG 205, 3:30 PM
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Permafrost in the high northern latitudes contains a vast reservoir of Mercury (Hg), more than the atmosphere, the ocean, and the rest of the land surface combined. The naturally-occurring Hg bonds to organic matter and has accumulated in permafrost over thousands of years. As temperatures rise in the future, the permafrost will thaw and the organic matter will decay, releasing Hg into the environment.
Here, we quantify the amount of Hg in permafrost and explain how it got there. We estimate future releases of Hg from thawing permafrost for multiple scenarios of potential future climate and explore how this may increase Hg concentrations in fish, a key food source.
Thawing permafrost could release Hg in magnitudes comparable to annual anthropogenic emissions from burning coal, indicating an irreversible tipping point of the Arctic system that will impact the global Hg cycle for centuries.
[video:https://vimeo.com/645443736]
