What the geological past can tell us about the future of the ocean’s twilight zone

Paleontological reconstructions of plankton community structure during warm periods of the Cenozoic (last 66 million years) reveal that deep-dwelling ‘twilight zone’ (200–1000 m) plankton were less abundant and diverse, and lived much closer to the surface, than in colder, more recent climates. We s...

Full description

Saved in:
Bibliographic Details
Published inNature communications Vol. 14; no. 1; p. 2376
Main Authors Crichton, Katherine A., Wilson, Jamie D., Ridgwell, Andy, Boscolo-Galazzo, Flavia, John, Eleanor H., Wade, Bridget S., Pearson, Paul N.
Format Journal Article
LanguageEnglish
Published London Nature Publishing Group UK 27.04.2023
Nature Publishing Group
Nature Portfolio
Subjects
704/106/413
704/106/694/1108
704/47/4113
704/829/826
Anthropogenic factors
Carbon Cycle
Cenozoic
Community structure
Dissolved oxygen
Emissions
Food
Food supply
Geology
Human influences
Humanities and Social Sciences
multidisciplinary
Oceans and Seas
Organic matter
Plankton
Science
Science (multidisciplinary)
Seawater - chemistry
Temperature
Online AccessGet full text

Cover

More Information
Summary:Paleontological reconstructions of plankton community structure during warm periods of the Cenozoic (last 66 million years) reveal that deep-dwelling ‘twilight zone’ (200–1000 m) plankton were less abundant and diverse, and lived much closer to the surface, than in colder, more recent climates. We suggest that this is a consequence of temperature’s role in controlling the rate that sinking organic matter is broken down and metabolized by bacteria, a process that occurs faster at warmer temperatures. In a warmer ocean, a smaller fraction of organic matter reaches the ocean interior, affecting food supply and dissolved oxygen availability at depth. Using an Earth system model that has been evaluated against paleo observations, we illustrate how anthropogenic warming may impact future carbon cycling and twilight zone ecology. Our findings suggest that significant changes are already underway, and without strong emissions mitigation, widespread ecological disruption in the twilight zone is likely by 2100, with effects spanning millennia thereafter. Combining geological evidence and modelling, Crichton and others find life in the ocean Twilight Zone (200 m to 1000 m depth) is vulnerable to warming due to lower food supply. High emissions may lead to severe depletion and extinction in this habitat
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:2041-1723
2041-1723
DOI:10.1038/s41467-023-37781-6