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Title: Autonomous Wintertime Observations of Air‐Sea Exchange in the Gulf Stream Reveal a Perfect Storm for Ocean CO 2 Uptake
Abstract

A scarcity of wintertime observations of surface ocean carbon dioxide partial pressure (pCO2) in and near the Gulf Stream creates uncertainty in the magnitude of the regional carbon sink and its controlling mechanisms. Recent observations from an Uncrewed Surface Vehicle (USV), outfitted with a payload to measure surface ocean and lower atmospherepCO2, revealed sharp gradients in oceanpCO2across the Gulf Stream. Surface oceanpCO2was lower by ∼50 μatm relative to the atmosphere in the subtropical mode water (STMW) formation region. This undersaturation combined with strong wintertime winds allowed for rapid ocean uptake of CO2, averaging −11.5 mmol m−2 day−1during the February 2019 USV mission. The unique timing of this mission revealed active STMW formation. The USV proved to be a useful tool for CO2flux quantification in the poorly observed, dynamic western boundary current environment.

 
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NSF-PAR ID:
10369728
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
49
Issue:
5
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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