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Variability in the sensitivity among model simulations of permafrost and carbon dynamics in the permafrost region between 1960 and 2009

McGuire, A. David; Koven, Charles; Lawrence, David M.; Clein, Joy S.; Xia, Jiangyang; Beer, Christian; Burke, Eleanor; Chen, Guangsheng; Chen, Xiaodong and Delire, Christine, et al. (2016) In Global Biogeochemical Cycles 30(7). p.1015-1037
Abstract

A significant portion of the large amount of carbon (C) currently stored in soils of the permafrost region in the Northern Hemisphere has the potential to be emitted as the greenhouse gases CO2 and CH4 under a warmer climate. In this study we evaluated the variability in the sensitivity of permafrost and C in recent decades among land surface model simulations over the permafrost region between 1960 and 2009. The 15 model simulations all predict a loss of near-surface permafrost (within 3 m) area over the region, but there are large differences in the magnitude of the simulated rates of loss among the models (0.2 to 58.8 × 103 km2 yr−1). Sensitivity simulations indicated that... (More)

A significant portion of the large amount of carbon (C) currently stored in soils of the permafrost region in the Northern Hemisphere has the potential to be emitted as the greenhouse gases CO2 and CH4 under a warmer climate. In this study we evaluated the variability in the sensitivity of permafrost and C in recent decades among land surface model simulations over the permafrost region between 1960 and 2009. The 15 model simulations all predict a loss of near-surface permafrost (within 3 m) area over the region, but there are large differences in the magnitude of the simulated rates of loss among the models (0.2 to 58.8 × 103 km2 yr−1). Sensitivity simulations indicated that changes in air temperature largely explained changes in permafrost area, although interactions among changes in other environmental variables also played a role. All of the models indicate that both vegetation and soil C storage together have increased by 156 to 954 Tg C yr−1 between 1960 and 2009 over the permafrost region even though model analyses indicate that warming alone would decrease soil C storage. Increases in gross primary production (GPP) largely explain the simulated increases in vegetation and soil C. The sensitivity of GPP to increases in atmospheric CO2 was the dominant cause of increases in GPP across the models, but comparison of simulated GPP trends across the 1982–2009 period with that of a global GPP data set indicates that all of the models overestimate the trend in GPP. Disturbance also appears to be an important factor affecting C storage, as models that consider disturbance had lower increases in C storage than models that did not consider disturbance. To improve the modeling of C in the permafrost region, there is the need for the modeling community to standardize structural representation of permafrost and carbon dynamics among models that are used to evaluate the permafrost C feedback and for the modeling and observational communities to jointly develop data sets and methodologies to more effectively benchmark models.

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publication status
published
subject
keywords
carbon cycle, climate change, permafrost, permafrost carbon feedback, sensitivity, soil carbon
in
Global Biogeochemical Cycles
volume
30
issue
7
pages
23 pages
publisher
American Geophysical Union
external identifiers
  • scopus:84978289190
  • wos:000382582400004
ISSN
0886-6236
DOI
10.1002/2016GB005405
language
English
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yes
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6404e0b6-63dd-454b-b35e-022bd350948e
date added to LUP
2016-10-11 17:13:34
date last changed
2017-09-24 05:01:44
@article{6404e0b6-63dd-454b-b35e-022bd350948e,
  abstract     = {<p>A significant portion of the large amount of carbon (C) currently stored in soils of the permafrost region in the Northern Hemisphere has the potential to be emitted as the greenhouse gases CO<sub>2</sub> and CH<sub>4</sub> under a warmer climate. In this study we evaluated the variability in the sensitivity of permafrost and C in recent decades among land surface model simulations over the permafrost region between 1960 and 2009. The 15 model simulations all predict a loss of near-surface permafrost (within 3 m) area over the region, but there are large differences in the magnitude of the simulated rates of loss among the models (0.2 to 58.8 × 10<sup>3</sup> km<sup>2</sup> yr<sup>−1</sup>). Sensitivity simulations indicated that changes in air temperature largely explained changes in permafrost area, although interactions among changes in other environmental variables also played a role. All of the models indicate that both vegetation and soil C storage together have increased by 156 to 954 Tg C yr<sup>−1</sup> between 1960 and 2009 over the permafrost region even though model analyses indicate that warming alone would decrease soil C storage. Increases in gross primary production (GPP) largely explain the simulated increases in vegetation and soil C. The sensitivity of GPP to increases in atmospheric CO<sub>2</sub> was the dominant cause of increases in GPP across the models, but comparison of simulated GPP trends across the 1982–2009 period with that of a global GPP data set indicates that all of the models overestimate the trend in GPP. Disturbance also appears to be an important factor affecting C storage, as models that consider disturbance had lower increases in C storage than models that did not consider disturbance. To improve the modeling of C in the permafrost region, there is the need for the modeling community to standardize structural representation of permafrost and carbon dynamics among models that are used to evaluate the permafrost C feedback and for the modeling and observational communities to jointly develop data sets and methodologies to more effectively benchmark models.</p>},
  author       = {McGuire, A. David and Koven, Charles and Lawrence, David M. and Clein, Joy S. and Xia, Jiangyang and Beer, Christian and Burke, Eleanor and Chen, Guangsheng and Chen, Xiaodong and Delire, Christine and Jafarov, Elchin and MacDougall, Andrew H. and Marchenko, Sergey and Nicolsky, Dmitry and Peng, Shushi and Rinke, Annette and Saito, Kazuyuki and Zhang, Wenxin and Alkama, Ramdane and Bohn, Theodore J. and Ciais, Philippe and Decharme, Bertrand and Ekici, Altug and Gouttevin, Isabelle and Hajima, Tomohiro and Hayes, Daniel J. and Ji, Duoying and Krinner, Gerhard and Lettenmaier, Dennis P. and Luo, Yiqi and Miller, Paul A. and Moore, John C. and Romanovsky, Vladimir and Schädel, Christina and Schaefer, Kevin and Schuur, Edward A G and Smith, Benjamin and Sueyoshi, Tetsuo and Zhuang, Qianlai},
  issn         = {0886-6236},
  keyword      = {carbon cycle,climate change,permafrost,permafrost carbon feedback,sensitivity,soil carbon},
  language     = {eng},
  number       = {7},
  pages        = {1015--1037},
  publisher    = {American Geophysical Union},
  series       = {Global Biogeochemical Cycles},
  title        = {Variability in the sensitivity among model simulations of permafrost and carbon dynamics in the permafrost region between 1960 and 2009},
  url          = {http://dx.doi.org/10.1002/2016GB005405},
  volume       = {30},
  year         = {2016},
}