Methane Emissions from Arctic Melting May Carry $60 Trillion Cost
In the July 2013 issue of the journal Nature, a study by Gail Whitman, Chris Hope, and Peter Wadhams quantifies the costs of methane release due to melting permafrost below the East Siberian Sea. The authors’ models found that the methane release–which is not accounted for in current climate models–will have an average estimated cost of $60 trillion without mitigating action, and will bring forward the timetable for 2℃ warming by 15 to 35 years.
The study counters existing scholarship that solely focuses on the benefits of melting in the Arctic–namely, improved opportunities for polar shipping and resource extraction. The authors contend that warming in the Arctic–a critical region that governs many global climate cycles–carries acute risks that far outweigh the benefits garnered through warming; the authors note the cost of Arctic warming will be borne disproportionately by developing countries, which will struggle with extreme weather, higher sea levels, and lowered agricultural protection due to climate changes driven by Arctic warming.
Whitman, Hope, and Wadhams simulated Arctic warming through the use of PAGE09, an integrated assessment model that values the costs of climate change, abatement, and adaptation. The authors ran 10,000 repetitions of the model in a Monte Carlo simulation to find confidence intervals and ranges of risk. Release of methane from the East Siberian Sea’s permafrost–containing over 50 Gt (gigatonnes) of methane–was simulated under various emissions scenarios and release scenarios.
The findings of the study echo themes expressed in the first Global Conference on Oceans, Climate, and Security at UMass Boston–that climate change is a threat multiplier, that Earth systems are fluid and interlinked, and that climate impacts on oceans pose acute threats to human security.
The Whitman, Hope, and Wadhams study can be found here. A white paper produced at the Global Conference on Oceans, Climate, and Security can be found here. Analysis of the Nature study by Responding to Climate Change, an NGO observer of climate issues, is available here.