Submesoscale streamers exchange water on the north wall of the Gulf Stream

Date

2016

Authors

Klymak, Jody M.
Shearman, R. Kipp
Gula, Jonathan
Lee, Craig M.
D'Asaro, Eric A.
Thomas, Leif N.
McWilliams, James C.

Journal Title

Journal ISSN

Volume Title

Publisher

Geophysical Research Letters

Abstract

The Gulf Stream is a major conduit of warm surface water from the tropics to the subpolar North Atlantic. Here we observe and simulate a submesoscale (<20 km) mechanism by which the Gulf Stream exchanges water with subpolar water to the north. Along isopycnals, the front has a sharp compensated temperature‐salinity contrast, with distinct mixed water between the two water masses 2 and 4 km wide. This mixed water does not increase downstream despite substantial energy available for mixing. A series of streamers detrain this water at the crest of meanders. Subpolar water replaces the mixed water and resharpens the front. The water mass exchange accounts for a northward flux of salt of 0.5–2.5 psu m2 s−1, (large‐scale diffusivity O (100 m2 s−1)). This is similar to bulk‐scale flux estimates of 1.2 psu m2 s−1 and supplies fresher water to the Gulf Stream required for the production of 18° subtropical mode water.

Description

Keywords

ocean mixing, Gulf Stream, submesoscale mixing, eddies

Citation

Klymak, J. M., Shearman, R. K., Gula, J., Lee, C. M., D;Asaro, E. A., Thomas, L. N., & McWilliams, J. C. (2016). Submesoscale streamers exchange water on the north wall of the Gulf Stream. Geophysical Research Letters, 43(3), 1226-1233. https://doi.org/10.1002/2015GL067152.