May 4, 2012

Significant contribution to climate warming from the permafrost carbon feedback

by
Andrew H. MacDougall, Christopher A. Avis & Andrew J. Weaver
,
Nature
  • States that permafrost soils contain an estimated 1,700 Pg of carbon, almost twice the present atmospheric carbon pool
  • Uses a coupled global climate model to quantify the magnitude of the warming generated by the feedback between permafrost carbon release and climate
  • According to the authors' simulations, permafrost soils will release between 68 and 508 Pg carbon by 2100
  • Shows that the additional surface warming generated by the feedback between permafrost carbon and climate is independent of the pathway of anthropogenic emissions followed in the twenty-first century
  • Estimates that this feedback could result in an additional warming of 0.13–1.69 °C by 2300
  • Shows that the upper bound for the strength of the feedback is reached under the less intensive emissions pathways
  • Suggests that permafrost carbon release could lead to significant warming, even under less intensive emissions trajectories