Surface circulation in the Solomon Sea derived from Lagrangian drifter observations
Hristova, H.G. and W.S. Kessler
J. Phys. Oceanogr., Accepted
Abstract
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.
Dr. William S. Kessler
NOAA / PMEL / OCRD
7600 Sand Point Way NE
Seattle WA 98115 USA
