Methane concentration and delta deuterium of methane from the NGRIP ice core

DOI

The causes of past changes in the global methane cycle and especially the role of marine methane hydrate (clathrate) destabilization events are a matter of debate. Here we present evidence from the North Greenland Ice Core Project ice core based on the hydrogen isotopic composition of methane [dD(CH4)] that clathrates did not cause atmospheric methane concentration to rise at the onset of Dansgaard-Oeschger (DO) events 7 and 8. Box modeling supports boreal wetland emissions as the most likely explanation for the interstadial increase. Moreover, our data show that dD(CH4) dropped 500 years before the onset of DO 8, with CH4 concentration rising only slightly. This can be explained by an early climate response of boreal wetlands, which carry the strongly depleted isotopic signature of high-latitude precipitation at that time.

Uncertainty for dD of CH4 is 3.4 per mil as derived from standard measurements as described in: Bock, M. et al., 2010, doi:10.1002/rcm.4429Please note, that the concentration data given here have a higher error (of 29 ppbv 1-sigma) compared to conventional methods due to the uncertainty of total air content determination of the dD isotope system.

Supplement to: Bock, Michael; Schmitt, Jochen; Möller, Lars; Spahni, Renato; Blunier, Thomas; Fischer, Hubertus (2010): Hydrogen isotopes preclude marine hydrate CH4 emissions at the onset of Dansgaard-Oeschger Events. Science, 328(5986), 1686-1689

Identifier
DOI https://doi.org/10.1594/PANGAEA.756715
Related Identifier https://doi.org/10.1126/science.1187651
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.756715
Provenance
Creator Bock, Michael ORCID logo; Schmitt, Jochen ORCID logo; Möller, Lars ORCID logo; Spahni, Renato; Blunier, Thomas ORCID logo; Fischer, Hubertus ORCID logo
Publisher PANGAEA
Publication Year 2010
Funding Reference German Research Foundation https://doi.org/10.13039/501100001659 Crossref Funder ID 5472008 https://gepris.dfg.de/gepris/projekt/5472008 Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 288 data points
Discipline Earth System Research
Spatial Coverage (-42.320 LON, 75.100 LAT); Greenland