By Gail Riekie. 15th September 2010.
Earlier in the year, we reported on a paper published in the journal Science which presented results from an extensive survey of methane emissions on the East Siberian Arctic Shelf (Shakhova et al., 2010) and highlighted a methane source of previously unrecognised magnitude. (See ‘Supersaturated Siberian Seas’).
Science (vol. 329, 3 September 2010) has now published a letter from Vasilii Petrenko and several fellow methane researchers, which raises issues regarding the way that Shakhova et al. cited earlier papers in support of their statement that methane released from thawing permafrost is a “likely positive feedback to climate warming”. A response to the letter, from Shakhova and two colleagues, defending their use of the references, is also published.
The main findings of the Shakhova paper are not in contention. The debate does however highlight at least two important issues for researchers in the field of methane and climate. Firstly, as Petrenko and colleagues point out, with increasing scrutiny of climate science, absolute clarity in communicating the evidence is essential. The second, as noted by Shakhova’s reply, is the scarcity to date of large scale studies which address the increasingly important subject of climate-biogeochemistry feedback processes in the Arctic.
NERC’s recent Arctic funding announcement implicitly recognises this gap in knowledge, and in the not too distant future we hope to be reporting on innovative new projects which will reduce current uncertainties in the relationship between climate and Arctic methane release.
Natalia Shakhova, Igor Semiletov, Anatoly Salyuk, Vladimir Yusupov, Denis Kosmach, and Örjan Gustafsson. 2010. Science 1246-1250.