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Title: Atmospheric pCO 2 Response to Stimulated Organic Carbon Export: Sensitivity Patterns and Timescales
Abstract The ocean's organic carbon export is a key control on atmospheric pCO2and stimulating this export could potentially mitigate climate change. We use a data‐constrained model to calculate the sensitivity of atmospheric pCO2to local changes in export using an adjoint approach. A perpetual enhancement of the biological pump's export by 0.1 PgC/yr could achieve a roughly 1% reduction in pCO2at average sensitivity. The sensitivity varies roughly 5‐fold across different ocean regions and is proportional to the difference between the mean sequestration timeτseqof regenerated carbon and the response timeτpreof performed carbon, which is the reduction in the preformed carbon inventory per unit increase in local export production. Air‐sea CO2disequilibrium modulates the geographic pattern ofτpre, causing particularly high sensitivities (2–3 times the global mean) in the Antarctic Divergence region of the Southern Ocean.  more » « less
Award ID(s):
1948955
PAR ID:
10519194
Author(s) / Creator(s):
; ;
Publisher / Repository:
John Wiley and Sons
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
12
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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