Net primary production in the Gulf Stream sustained by quasi-geostrophic vertical exchanges

Ananda Pascual (IMEDEA(CSIC-UIB), Spain)


Bruno Buongiorno Nardelli (CNR, Italy); Simón Ruiz (IMEDEA(CSIC-UIB), Spain); Daniele Iudicone (Stazione Zoologica, Italy); Stéphanie Guinehut (CLS, France); Diane Galbrun (ENSTA ParisTech, France); Peter Gaube (University of Whashington, US); Miguel Capllonch (IMEDEA(CSIC-UIB), Spain)

Event: 2015 Ocean Surface Topography Science Team Meeting

Session: Science II: Mesoscale and sub-mesoscale ocean processes: current understanding and preparation for SWOT

Presentation type: Type Poster

We analyze 12 years of mesoscale vertical motion derived from an observation-based product in the top 1000 m of the North West Atlantic Ocean. Vertical velocities [O(10 m day-1)] associated with Gulf Stream instabilities consist of alternating cells of upwelling and downwelling. Here we show that the magnitude of the vertical motions decays exponentially southwards with an e-folding length scale is informative on the dynamics of the system. We further investigate the impact of the vertical supply of nutrients on phytoplankton growth with a conceptual model incorporating the mean effect of nutrient distribution, quasi-geostrophic dynamics and Ekman suction/pumping. Results confirm that the mean effect of mesoscale vertical velocity variability alone can sustain observed levels of net primary production in the immediate vicinity of the Gulf Stream, while other mechanisms, including horizontal advection and submesoscale dynamics, need to be considered when moving towards the subtropical gyre.

Poster show times:

RoomStart DateEnd Date
Grand Ballroom Foyer Thu, Oct 22 2015,11:00 Thu, Oct 22 2015,18:00
Ananda Pascual