Work

Carbon isotope budget indicates biological disequilibrium dominated ocean carbon storage at the Last Glacial Maximum

Year: 2024

Type: article

Abstract: Understanding the causes of the ~90 ppmv atmospheric CO 2 swings between glacial and interglacial climates is an important open challenge in paleoclimate research. Although the regularity of the glacial-interglacial cycles hints at a single driving mechanism, Earth System models require many independent physical and biological processes to explain the full observed CO 2 signal. Here we show that biologically sequestered carbon in the ocean can explain an atmospheric CO 2 change of 75 ± 40 ppmv, based on a mass balance calculation using published carbon isotopic measurements. An analysis of the carbon isotopic signatures of different water masses indicates similar regenerated carbon inventories at the Last Glacial Maximum and during the Holocene, requiring that the change in carbon storage was dominated by disequilibrium. We attribute the inferred change in carbon disequilibrium to expansion of sea-ice or change in the overturning circulation.

Source: Nature Communications

DOI: 10.1038/s41467-024-52360-z

Authors: Anne Willem Omta, Christopher L. Follett, Jonathan M. Lauderdale, Raffaele Ferrari

Institutions: Case Western Reserve University, University of Liverpool, Massachusetts Institute of Technology

Language: English

Topic: Geology and Paleoclimatology Research

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $6,790