SLS - Mara Freilich
Pathways of vertical carbon fluxes
Oceanic fronts play an outsized role in global biogeochemical cycling as hotspots of primary production and subduction of carbon and oxygen from the surface to the ocean interior. The influence of frontal dynamics on biogeochemical cycles depends on both the pathways of vertical transport and on the ways that microbial communities respond to the enhanced vertical motion at fronts. I investigate the rate and pathways of exchange between the oceanic mixed layer and thermocline using process study models and Lagrangian analysis methods. The interaction between mesoscale and submesoscale frontal instabilities generates a variety of subduction pathways associated with mesoscale frontogenesis, submesoscale filaments, and submesoscale eddies. The influence of these subduction pathways on biogeochemical fluxes depends on the relative time scales of vertical transport and nutrient uptake. Biogeochemical fluxes are largest when the biological timescale matches the vertical velocity frequency. This means that different ocean dynamical regimes are likely to support different phytoplankton growth rates. These modeling studies are used to interpret observations of carbon fluxes at fronts from the Western Mediterranean.
About this Series:
The Atmosphere, Ocean and Climate Sack Lunch Seminar Series is an informal seminar series within PAOC that focuses on more specialized topics than the PAOC Colloquium. Seminar topics include all research concerning the science of atmosphere, ocean and climate. The seminars usually take place on Wednesdays from 12-1pm. The presentations are either given by an invited speaker or by a member of PAOC and can focus on new research or discussion of a paper of particular interest.