Authors' Summary: The differences in phytoplankton variability through time observed at fixed locations (Eulerian perspective) or following water parcels (Lagrangian perspective) are poorly understood. We created a large set of satellite chlorophyll matched time series pairs in the Eulerian and Lagrangian perspective, using global drifter trajectories as an approximation of how surface ocean currents move.

We found that for most ocean locations, chlorophyll variability measured in Eulerian and Lagrangian perspectives is not different. In high latitude zones, chlorophyll appears to vary similarly over large areas. However, in localized regions of the ocean, such as western boundary currents and upwelling regions, chlorophyll variability in these two perspectives may significantly differ. The causes are linked to the specific ocean dynamics of each area.