Old carbon reservoirs were not important in the deglacial methane budget

Permafrost and methane hydrates are large, climate-sensitive old carbon reservoirs that have the potential to emit large quantities of methane, a potent greenhouse gas, as the Earth continues to warm. We present ice core isotopic measurements of methane (Δ14C, δ13C, and δD) from the last deglaciation, which is a partial analog for modern warming. Our results show that methane emissions from old carbon reservoirs in response to deglacial warming were small (<19 teragrams of methane per year, 95% confidence interval) and argue against similar methane emissions in response to future warming. Our results also indicate that methane emissions from biomass burning in the pre-Industrial Holocene were 22 to 56 teragrams of methane per year (95% confidence interval), which is comparable to today.

Details

Publication status:
Published
Author(s):
Authors: Dyonisius, M.N., Petrenko, V.V., Smith, A.M., Hua, Q., Yang, B., Schmitt, J., Beck, J., Seth, B., Bock, M., Hmiel, B., Vimont, I., Menking, J.A., Shackleton, S.A., Baggenstos, D., Bauska, T.K. ORCIDORCID record for T.K. Bauska, Rhodes, R.H., Sperlich, P., Beaudette, R., Harth, C., Kalk, M., Brook, E.J., Fischer, H., Severinghaus, J.P., Weiss, R.F.

On this site: Thomas Bauska
Date:
21 February, 2020
Journal/Source:
Science / 367
Page(s):
907-910
Digital Object Identifier (DOI):
https://doi.org/10.1126/science.aax0504