Atmospheric constraints on the methane emissions from the East Siberian Shelf

作者：Berchet Antoine; Bousquet Philippe; Pison Isabelle; Locatelli Robin; Chevallier Frederic; Paris Jean Daniel; Dlugokencky Ed J; Laurila Tuomas; Hatakka Juha; Viisanen Yrjo; Worthy Doug E J; Ni**et Euan; Fisher Rebecca; France James; Lowry David; Ivakhov Viktor; Hermansen Ove

来源：Atmospheric Chemistry and Physics, 2016, 16(6): 4147-4157.

DOI：10.5194/acp-16-4147-2016

Subsea permafrost and hydrates in the East Siberian Arctic Shelf (ESAS) constitute a substantial carbon pool, and a potentially large source of methane to the atmosphere. Previous studies based on interpolated oceanographic campaigns estimated atmospheric emissions from this area at 8-17 TgCH(4) yr(-1). Here, we propose insights based on atmospheric observations to evaluate these estimates. The comparison of high-resolution simulations of atmospheric methane mole fractions to continuous methane observations during the whole year 2012 confirms the high variability and heterogeneity of the methane releases from ESAS. A reference scenario with ESAS emissions of 8 TgCH(4) yr(-1), in the lower part of previously estimated emissions, is found to largely overestimate atmospheric observations in winter, likely related to overestimated methane leakage through sea ice. In contrast, in summer, simulations are more consistent with observations. Based on a comprehensive statistical analysis of the observations and of the simulations, annual methane emissions from ESAS are estimated to range from 0.0 to 4.5 TgCH(4) yr(-1). Isotopic observations suggest a biogenic origin (either terrestrial or marine) of the methane in air masses originating from ESAS during late summer 2008 and 2009.

• 出版日期2016
• 单位中国地震局