PHY-02 Atlantic Ocean Variability
The role of submesoscale circulations in modulating deep water formation in the Labrador Sea
Annalisa Bracco* , Georgia Tech
Filippos Tagklis, NOAA AOML
Takamitsu Ito, Georgia Tech

In this presentation we discuss transport pathways and the ultimate fate of the Irminger Current water from the continental slope to Labrador Sea interior using a suite of regional ocean simulations. We find that submesoscale processes modulate this transport and in turn the stratification of the Labrador Sea interior, by controlling the characteristics of the coherent vortices formed along West Greenland. Submesoscale circulations modify and control the Labrador Sea contribution to the global meridional overturning, with a linear relationship between time-averaged near surface vorticity and/or frontogenetic tendency along the west coast of Greenland, and volume of convected water. This research puts into contest the lesser role of the Labrador Sea in the overall control of the state of the MOC argued through the analysis of recent OSNAP (Overturning in the Subpolar North Atlantic Program) data with respect to estimates from climate models. It also confirms that submesoscale turbulence scales-up to climate relevance, pointing to the urgency of including its advective contribution in Earth systems models.