Spatial and temporal interplay between oceanic circulation and
biological production in shaping carbon export off the California coast
Abstract
A major challenge in understanding the oceanic carbon cycle is
estimating the downward flux of organic carbon exiting the sunlit
surface ocean, termed carbon export. Existing algorithms derive carbon
export from satellite ocean color, but neglect spatio-temporal offsets
created by the temporal lag between production and export, and by
horizontal advection. Here, we show that a Lagrangian
“growth-advection” (GA) satellite-derived product, where plankton
succession and export are mapped onto surface oceanic circulation
following coastal upwelling, succeeds in representing in situ export off
the California coast. In situ export is best represented by a
combination of GA export (proportional to modeled zooplankton) and
export derived from ocean color (related to local phytoplankton). Both
products also correlate with a long-term time series of abyssal carbon
flux. These results provide insights on export spatio-temporal patterns
and a path towards improving satellite-derived carbon export in the
California Current and beyond.