Plankton blooms in vortices: The role of biological and hydrodynamic time scales

TL;DR

This paper investigates how mesoscale hydrodynamic structures and biological processes interact to create localized plankton blooms near islands, emphasizing the importance of flow dynamics and nutrient retention.

Contribution

It introduces a coupled model combining flow dynamics and marine ecosystem interactions to explain localized plankton blooms in vortices.

Findings

Vortices can trap nutrients and plankton, promoting blooms.

Long residence times near islands enhance plankton growth.

Confinement within vortices is crucial for bloom formation.

Abstract

We study the interplay of hydrodynamic mesoscale structures and the growth of plankton in the wake of an island, and its interaction with a coastal upwelling. Our focus is on a mechanism for the emergence of localized plankton blooms in vortices. Using a coupled system of a kinematic flow mimicking the mesoscale structures behind the island and a simple three component model for the marine ecosystem, we show that the long residence times of nutrients and plankton in the vicinity of the island and the confinement of plankton within vortices are key factors for the appearance of localized plankton blooms