Surface Circulation in the Solomon Sea Derived from Lagrangian Drifter Observations*

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). The seasonal velocity signal has the largest magnitude narrowly along the double western boundary formed by the eastern coastlines of New Guinea and the Solomon Islands, suggesting that direct wind driving with its much larger spatial scales is not the main influence. 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.

From the subtropics to the central equatorial Pacific Ocean: Neodymium isotopic composition and rare earth element concentration variations

“…Currents are determined from ORCA025 climatology of September, corresponding to EUC‐Fe cruise period, from Reverdin et al . [] and from Hristrova and Kessler []. They are represented by grey arrows (dashed arrows = westward equatorial currents).…”

Water mass analysis of the Coral Sea through an Optimum Multiparameter method

“…East of 157°E at the Solomon Sea entrance, the water mass composition is not well resolved. Southward currents have been observed in this area [ Cravatte et al ., ; Davis et al ., ; Gasparin et al ., ; Hristova and Kessler , ; Kessler and Cravatte , ]. Besides we suspect water contributions from the Solomon Strait [ Cravatte et al ., ], or from the Indispensable Strait [ Gasparin et al ., ] which would explain the poor resolution.…”

Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia

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