A recent decline in North Atlantic subtropical mode water formation

Type Article
Date 2020-04
Language English
Author(s) Stevens Samuel W.1, 2, Johnson Rodney J.2, Maze GuillaumeORCID3, Bates Nicholas R.2, 4
Affiliation(s) 1 : Earth, Ocean and Atmospheric Sciences Department, University of British Columbia, Vancouver, British Columbia, Canada
2 : Bermuda Institute of Ocean Sciences, St. George’s, Bermuda
3 : Ifremer, University of Brest, CNRS, IRD, Laboratoire d’Océanographie Physique et Spatiale (LOPS), IFREMER, Brest, France
4 : Ocean and Earth Science Department, University of Southampton, Southampton, UK
Source Nature Climate Change (1758-678X) (Springer Science and Business Media LLC), 2020-04 , Vol. 10 , N. 4 , P. 335–341
DOI 10.1038/s41558-020-0722-3
WOS© Times Cited 10

As a manifestation of mixing dynamics in the upper ocean, interannual and decadal variability of subtropical mode water (STMW) properties in the North Atlantic Ocean provides a valuable insight into ocean–atmosphere interaction in a changing climate. Here, we use hydrographic data from the Bermuda Atlantic Time-Series Study and Hydrostation S sites near Bermuda, as well as various ocean reanalysis products, to evaluate the modern variability of STMW properties. Our study finds an 86–93% loss of STMW thickness at these sites between 2010 and 2018 and a comparable loss throughout the western subtropical gyre, culminating in the weakest STMW pentad on record. We correlate this decline with a reduction in the annual outcropping volume and northward excursions of the formation region, suggesting a gyre-wide signal of weakening STMW generation. The outcropping volume of STMW is anti-correlated with surface ocean heat content, foreshadowing future STMW loss in the face of continued warming.

Full Text
File Pages Size Access
15 7 MB Access on demand
54 KB Access on demand
53 KB Access on demand
53 KB Access on demand
53 KB Access on demand
53 KB Access on demand
53 KB Access on demand
4 614 KB Access on demand
Author's final draft 39 4 MB Open access
Publisher Correction 1 524 KB Open access
Top of the page