The Atlantic Ocean surface microlayer from 50°N to 50°S is ubiquitously enriched in surfactants at wind speeds up to 13m s -1

• Main Authors: Sabbaghzadeh B, Upstill-Goddard RC, Beale R, Pereira R, Nightingale PD
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Wiley-Blackwell
• Subjects: North Atlantic
• Online Access: https://eprint.ncl.ac.uk/fulltext.aspx?url=230187/5B4E853D-490B-457E-9987-A34104B96264.pdf&pub_id=230187

We report the first measurements of surfactant activity (SA) in the sea surface microlayer (SML) and in sub-surface waters (SSW) at the ocean basin scale, for two Atlantic Meridional Transects (AMT) from 50°N to 50°S during 2014 and 2015. Northern hemisphere (NH) SA was significantly higher than southern hemisphere (SH) SA in the SML and in the SSW. SA enrichment factors (EF = SA SML /SA SSW ) were also higher in the NH, for wind speeds up to ~13 m s -1 , questioning a prior assertion that Atlantic Ocean wind speeds > 12 m s -1 poleward of 30°N and 30°S would preclude high EFs and showing the SML to be self-sustaining with respect to SA. Our results imply that surfactants exert a control on air-sea CO 2 exchange across the whole North Atlantic CO 2 sink region and that the contribution made by high wind, high latitude oceans to air-sea gas exchange globally should be re-examined.