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Title: Toward a Cenozoic history of atmospheric CO 2

The geological record encodes the relationship between climate and atmospheric carbon dioxide (CO2) over long and short timescales, as well as potential drivers of evolutionary transitions. However, reconstructing CO2beyond direct measurements requires the use of paleoproxies and herein lies the challenge, as proxies differ in their assumptions, degree of understanding, and even reconstructed values. In this study, we critically evaluated, categorized, and integrated available proxies to create a high-fidelity and transparently constructed atmospheric CO2record spanning the past 66 million years. This newly constructed record provides clearer evidence for higher Earth system sensitivity in the past and for the role of CO2thresholds in biological and cryosphere evolution.

 
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Award ID(s):
1806015 2121325 2121649 1636005 2121170
NSF-PAR ID:
10480684
Author(s) / Creator(s):
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Corporate Creator(s):
 
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
382
Issue:
6675
ISSN:
0036-8075
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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