Work

A CO 2 greenhouse efficiently warmed the early Earth and decreased seawater 18 O/ 16 O before the onset of plate tectonics

Year: 2021

Type: article

Abstract: Significance Due to the lower luminosity of the young Sun, climate modelers struggle to explain why the climate on early Earth was not freezing cold. This “faint young Sun paradox” is in conflict with apparently hot Archean ocean temperatures (∼70 °C) that can be estimated from the 18 O/ 16 O stable isotope ratio of chemical sediments. We show that the later temperatures had been overestimated because the 18 O/ 16 O of seawater also changed over time due to intense carbonatization and silicification of the oceanic crust, which consumes heavy 18 O. Because these processes require high fluxes of CO 2 , greenhouse warming by a CO 2 -rich atmosphere appears most feasible to explain all observations.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.2023617118

Authors: Daniel Herwartz, Andreas Pack, Thorsten J. Nagel

Institutions: University of Cologne, University of Göttingen, Aarhus University

Language: English

Topic: Paleontology and Stratigraphy of Fossils

Subfield: Paleontology

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: bronze

OpenAlex ID: W3164850051

FWCI: 4.169

Cites: 61

Cited by: 37

Related to: 10