Influence of Tropical Instability Waves on Phytoplankton Biomass near the Marquesas Islands

Strong La Niña events, particularly the intense conditions of 1998 and 2010, trigger significant phytoplankton blooms near the Marquesas Islands by advecting iron-rich waters from the equatorial region via tropical instability waves (TIWs). This finding, derived from an 18-year analysis combining satellite observations, ocean re-analyses, and Lagrangian diagnostics, challenges earlier hypotheses that such advection occurs during all La Niña events. While TIWs primarily disperse and modulate existing phytoplankton plumes, their influence on biomass enhancement is limited to strong La Niña conditions, suggesting that other large-scale forcing mechanisms—such as thermocline uplift or coastal upwelling—play a dominant role in moderate events.

Martinez, E., Raapoto, H., Maes, C., & Maamaatuaihutapu, K. (2018). Influence of Tropical Instability Waves on Phytoplankton Biomass near the Marquesas Islands. Remote Sensing, 10(4), 640. https://doi.org/10.3390/rs10040640