Please use this identifier to cite or link to this item: https://oar.tib.eu/jspui/handle/123456789/477
Files in This Item:
File Description SizeFormat 
bg-9-649-2012.pdf1.66 MBAdobe PDFView/Open
bg-9-649-2012-supplement.pdf155.46 kBAdobe PDFView/Open
Title: Estimating the near-surface permafrost-carbon feedback on global warming
Authors: Schneider von Deimling, T.Meinshausen, M.Levermann, A.Huber, V.Frieler, K.Lawrence, D. M.Brovkin, V.
Publishers Version: https://doi.org/10.5194/bg-9-649-2012
Issue Date: 2012
Published in: Biogeosciences, Volume 9, Issue 2, Page 649-665
Publisher: München : European Geopyhsical Union
Abstract: Thawing of permafrost and the associated release of carbon constitutes a positive feedback in the climate system, elevating the effect of anthropogenic GHG emissions on global-mean temperatures. Multiple factors have hindered the quantification of this feedback, which was not included in climate carbon-cycle models which participated in recent model intercomparisons (such as the Coupled Carbon Cycle Climate Model Intercomparison Project – C4MIP) . There are considerable uncertainties in the rate and extent of permafrost thaw, the hydrological and vegetation response to permafrost thaw, the decomposition timescales of freshly thawed organic material, the proportion of soil carbon that might be emitted as carbon dioxide via aerobic decomposition or as methane via anaerobic decomposition, and in the magnitude of the high latitude amplification of global warming that will drive permafrost degradation. Additionally, there are extensive and poorly characterized regional heterogeneities in soil properties, carbon content, and hydrology. Here, we couple a new permafrost module to a reduced complexity carbon-cycle climate model, which allows us to perform a large ensemble of simulations. The ensemble is designed to span the uncertainties listed above and thereby the results provide an estimate of the potential strength of the feedback from newly thawed permafrost carbon. For the high CO2 concentration scenario (RCP8.5), 33–114 GtC (giga tons of Carbon) are released by 2100 (68 % uncertainty range). This leads to an additional warming of 0.04–0.23 °C. Though projected 21st century permafrost carbon emissions are relatively modest, ongoing permafrost thaw and slow but steady soil carbon decomposition means that, by 2300, about half of the potentially vulnerable permafrost carbon stock in the upper 3 m of soil layer (600–1000 GtC) could be released as CO2, with an extra 1–4 % being released as methane. Our results also suggest that mitigation action in line with the lower scenario RCP3-PD could contain Arctic temperature increase sufficiently that thawing of the permafrost area is limited to 9–23 % and the permafrost-carbon induced temperature increase does not exceed 0.04–0.16 °C by 2300.
Keywords: carbon cycle; carbon emission; climate modeling; estimation method; global warming; greenhouse gas; numerical model; permafrost; soil carbon; soil property; thawing; vulnerability
DDC: 550
License: CC BY 3.0 Unported
Link to License: https://creativecommons.org/licenses/by/3.0/
Appears in Collections:Geowissenschaften



This item is licensed under a Creative Commons License Creative Commons