Thermokarst amplifies fluvial inorganic carbon cycling and export across watershed scales on the Peel Plateau, Canada
As climate warming and precipitation increase at high latitudes, permafrost terrains across the circumpolar north are poised for intensified geomorphic activity and sediment mobilization that are expected to persist for millennia. In previously glaciated permafrost terrain, ice-rich deposits are ass...
| Published in: | Biogeosciences |
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| Main Authors: | , , , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Copernicus Publications
2020
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/bg-17-5163-2020 https://doaj.org/article/d86e3fe7affa4c5ebda4a9c396465515 |
| Summary: | As climate warming and precipitation increase at high latitudes, permafrost terrains across the circumpolar north are poised for intensified geomorphic activity and sediment mobilization that are expected to persist for millennia. In previously glaciated permafrost terrain, ice-rich deposits are associated with large stores of reactive mineral substrate. Over geological timescales, chemical weathering moderates atmospheric CO 2 levels, raising the prospect that mass wasting driven by terrain consolidation following thaw (thermokarst) may enhance weathering of permafrost sediments and thus climate feedbacks. The nature of these feedbacks depends upon the mineral composition of sediments (weathering sources) and the balance between atmospheric exchange of CO 2 vs. fluvial export of carbonate alkalinity ( Σ [ <math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msubsup><mi mathvariant="normal">HCO</mi><mn mathvariant="normal">3</mn><mo>-</mo></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="33pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="2fbeb9b29341401f243f2ced851d27df"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-17-5163-2020-ie00001.svg" width="33pt" height="16pt" src="bg-17-5163-2020-ie00001.png"/></svg:svg> , <math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><msubsup><mi mathvariant="normal">CO</mi><mn mathvariant="normal">3</mn><mrow><mn mathvariant="normal">2</mn><mo>-</mo></mrow></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="30pt" height="17pt" class="svg-formula" dspmath="mathimg" md5hash="c7035c2c75c9854db2b1eb7c42f957db"><svg:image ... |
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