Accelerated mobilization of organic carbon from retrogressive thaw slumps on the northern Taymyr Peninsula

• Published in: The Cryosphere
• Main Authors: Bernhard, Philipp, Zwieback, Simon, Hajnsek, Irena
• Format: Text
• Language: English
• Published: 2022
• Subjects: Arctic; Taymyr; Climate change; Ice; permafrost; Taymyr Peninsula
• Online Access: https://doi.org/10.5194/tc-16-2819-2022; https://tc.copernicus.org/articles/16/2819/2022/

With climate change, Arctic hillslopes above ice-rich permafrost are vulnerable to enhanced mass wasting and organic carbon mobilization. In this study we use TanDEM-X-derived (TerraSAR-X add-on for Digital Elevation Measurement; synthetic-aperture radar) digital elevation models to document an approximately 43-fold increase in thaw slumping and concomitant 28-fold increase in carbon mobilization on the northern Taymyr Peninsula from 2010 to 2021. The available observations allowed us to compare two time periods, from 2010/11 to 2016/17 and from 2017/18 to 2020/21, and contrast retrogressive thaw slump (RTS) activity between these periods. We find that all quantities describing RTS activity increased in the observed period. The total volumetric change per year increased from about 0.17×10 6 to <math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">7.4</mn><mo>×</mo><msup><mn mathvariant="normal">10</mn><mn mathvariant="normal">6</mn></msup><mspace width="0.125em" linebreak="nobreak"/><msup><mi mathvariant="normal">m</mi><mn mathvariant="normal">3</mn></msup><mspace width="0.125em" linebreak="nobreak"/><msup><mi mathvariant="normal">yr</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="82pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="72b5800938df71d4731eae140c9c33b8"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-16-2819-2022-ie00001.svg" width="82pt" height="15pt" src="tc-16-2819-2022-ie00001.png"/></svg:svg> , a 43-fold increase. The observed surge in RTS activity is mainly driven by the initiation of new RTS, indicated by the 17-fold increase in active RTS numbers from 82 to 1404 and the relatively ...