Fine-scale Air-sea Interactions Due to Oceanic Deep Jets

The finding of ubiquitous alternating east-west zonal jets (or striations) in the oceans at the surface and at depth by Maximenko (IPRC) et al., and by Nakano & Hasumi (University of Tokyo) less than a decade ago surprised oceanographers. Now the impact of these striations on the atmosphere has been explored at fine scales (3–5° meridionally) using CFES, a high-resolution, atmosphere-ocean coupled model developed at the JAMSTEC Earth Simulator Center. Fine-scale, quasi-barotropic zonal jets in the central south Pacific (panel a) generate fine-scale sea-surface temperature (SST) anomalies by zonal advection. The atmospheric boundary layer responds to these SST anomalies by generating fine-scale wind stress curl, which reinforces the original oceanic jets (panel b).

Latitude-time section of (a) depth-integrated zonal velocity of the ocean and (b) the Sverdrup flow from wind curl, averaged over 150–110°W.

B. Taguchi1, R. Furue2, N. Komori1, A. Kuwano-Yoshida1, M. Nonaka1, H. Sasaki1, and W. Ohfuchi1

1JAMSTEC, 2IPRCGeophys. Res. Lett. 39, 2012