Premium
Mechanistic insights into a hydrate contribution to the Paleocene‐Eocene carbon cycle perturbation from coupled thermohydraulic simulations
Author(s) -
Minshull T. A.,
MarínMoreno H.,
Armstrong McKay D. I.,
Wilson P. A.
Publication year - 2016
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2016gl069676
Subject(s) - methane , hydrate , carbon cycle , clathrate hydrate , dissociation (chemistry) , geology , deep sea , oceanography , environmental science , atmospheric sciences , chemistry , ecosystem , ecology , organic chemistry , biology
During the Paleocene‐Eocene Thermal Maximum (PETM), the carbon isotopic signature (δ 13 C) of surface carbon‐bearing phases decreased abruptly by at least 2.5 to 3.0‰. This carbon isotope excursion (CIE) has been attributed to widespread methane hydrate dissociation in response to rapid ocean warming. We ran a thermohydraulic modeling code to simulate hydrate dissociation due to ocean warming for various PETM scenarios. Our results show that hydrate dissociation in response to such warming can be rapid but suggest that methane release to the ocean is modest and delayed by hundreds to thousands of years after the onset of dissociation, limiting the potential for positive feedback from emission‐induced warming. In all of our simulations at least half of the dissociated hydrate methane remains beneath the seabed, suggesting that the pre‐PETM hydrate inventory needed to account for all of the CIE is at least double that required for isotopic mass balance.