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  • Projected reversal of the oceanic stable carbon isotope ratio depth gradient with continued anthropogenic carbon emissions
Title: Projected reversal of the oceanic stable carbon isotope ratio depth gradient with continued anthropogenic carbon emissions
Paleoceanographic records suggest that the present-day vertical gradient in the stable carbon isotopic composition (δ13C) of dissolved inorganic carbon in the ocean was reversed during the Paleocene-Eocene Thermal Maximum, an early period of relatively rapid release of carbon into the climate system. Here we present simulations from an observationally constrained ocean model under various greenhouse gas emissions scenarios. We project a decrease in the globally averaged δ13C of dissolved inorganic carbon in the surface ocean of between −1.8 to −6.3 ‰ by 2100. This reduction is driven by oceanic absorption of anthropogenic carbon dioxide, which is depleted in carbon-13. Our findings suggest an elimination or reversal of the natural vertical gradient in the δ13C of dissolved inorganic carbon by 2100 unless anthropogenic carbon emissions are reduced soon. We conclude that the Paleocene-Eocene Thermal Maximum is a geologic analogue of future global carbon cycle perturbations under continued rapid anthropogenic carbon emissions.  more » « less
Award ID(s):
1924215
PAR ID:
10356143
Author(s) / Creator(s):
Date Published:
Journal Name:
Communications earth environment
Volume:
3
ISSN:
2662-4435
Page Range / eLocation ID:
62
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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