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  • The reduced net carbon uptake over Northern Hemisphere land causes the close-to-normal CO 2 growth rate in 2021 La Niña
Title: The reduced net carbon uptake over Northern Hemisphere land causes the close-to-normal CO 2 growth rate in 2021 La Niña
La Niña climate anomalies have historically been associated with substantial reductions in the atmospheric CO2growth rate. However, the 2021 La Niña exhibited a unique near-neutral impact on the CO2growth rate. In this study, we investigate the underlying mechanisms by using an ensemble of net CO2fluxes constrained by CO2observations from the Orbiting Carbon Observatory-2 in conjunction with estimates of gross primary production and fire carbon emissions. Our analysis reveals that the close-to-normal atmospheric CO2growth rate in 2021 was the result of the compensation between increased net carbon uptake over the tropics and reduced net carbon uptake over the Northern Hemisphere mid-latitudes. Specifically, we identify that the extreme drought and warm anomalies in Europe and Asia reduced the net carbon uptake and offset 72% of the increased net carbon uptake over the tropics in 2021. This study contributes to our broader understanding of how regional processes can shape the trajectory of atmospheric CO2concentration under climate change.  more » « less
Award ID(s):
2017870
PAR ID:
10541249
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
23
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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