In the northernmost region of the earth the arctic permafrost is melting at an accelerated rate. For more than a decade, an international team of researchers from ETH Zurich, the University of Alaska Fairbanks, and the German ...
Risk for release of organic carbon
Their findings, recently published in the European Geosciences Union journal The Cryosphere, reveal substantial changes to the topography of Siberia's Taymyr peninsula, in northern Russia. The study's results reveal a strong, 43-fold increase in retrogressive thaw slump activity and a 28-fold increase in carbon mobilization. The increase also happens to coincide with an extreme heat wave that occurred in northern Siberia in 2020 in which temperatures reportedly reached 38 degrees Celsius (more than 100 degrees Fahrenheit)—record-breaking temperatures for the Arctic region.
"The strong increase in thaw slump activity due to the Siberian heatwave shows that carbon mobilization from permafrost soils can respond sharply and non-linearly to increasing temperatures," asserts the paper's lead author, Philipp Bernhard, Institute of Environmental Engineering, ETH Zurich.
Measuring changes to Arctic permafrost
Using satellite data, the research team has been able to develop a new method to quantify carbon mobilization in permafrost soil. Currently no other large-scale method exists that measures, to such a high level of spatial and vertical resolution, the changes in permafrost regions. This method allows researchers to provide a more accurate estimate of the state of the carbon cycle to the global carbon budget.
Retrogressive thaw slump, Mackenzie River Delta, Canada. Credit: ETH Zurich / Simon Zwieback
Sentinel-2 satellite elevation comparison of the Taymyr Peninsula in Siberia from Summer 2019 and 2021. The vegetation (red) change due to thaw slumps activity is clearly visible. Credit: European Space Agency (ESA) / ETH Zurich