Sensitivity of carbon budgets to permafrost carbon feedbacks and non-CO2 forcings

@article{MacDougall2015SensitivityOC,
  title={Sensitivity of carbon budgets to permafrost carbon feedbacks and non-CO2 forcings},
  author={Andrew H. MacDougall and Kirsten Zickfeld and Reto Knutti and H. Damon Matthews},
  journal={Environmental Research Letters},
  year={2015},
  volume={10}
}
The near proportionality between cumulative CO2 emissions and change in near surface temperature can be used to define a carbon budget: a finite quantity of carbon that can be burned associated with a chosen ‘safe’ temperature change threshold. Here we evaluate the sensitivity of this carbon budget to permafrost carbon dynamics and changes in non-CO2 forcings. The carbon budget for 2.0 ◦ C ?> of warming is reduced from 1320 Pg C when considering only forcing from CO2 to 810 Pg C when… 

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