Surface circulation in the Solomon Sea derived from Lagrangian drifter observations

Hristova, H.G. and W.S. Kessler

J. Phys. Oceanogr., Accepted

Velocity measurements from satellite-tracked surface drifters collected between 1994 and 2010 are used to map the surface circulation in the Solomon Sea, the last passageway for waters of subtropical origin flowing northward toward the equator where they replenish the Pacific warm pool. Pseudo-Eulerian statistics of the drifter observations show a strong seasonal cycle in both the mean circulation and the eddy kinetic energy in the region. The circulation is characterized by a strong northward flow from June to November (the season of strong southeasterly trade winds over the Solomon Sea), and a mostly southward flow with increased variability from December to May (when the winds over the Sea are weak). However, we find that direct wind driving is not the main influence on the surface velocity. In addition, the surface circulation exhibits substantial interannual variability of magnitude comparable to that of the seasonal cycle with velocity and temperature anomalies consistent with changes in the western boundary current acting to compensate for the discharge and recharge of the Pacific warm pool during ENSO.

horizontal black line
NOAA logo Dr. William S. Kessler
7600 Sand Point Way NE
Seattle WA 98115 USA
Tel:   206-526-6221
Fax:  206-526-6744
See also:    Kessler home page        Kessler publications         PMEL home page