Project: Collaborative Research: Physical-Biological Processes of Gulf Stream Warm Core Rings: Vertical Nutrient Delivery and Ecosystem Response

NSF abstract:

Warm core rings acting between western boundary currents and the continental shelf exert significant impact on the physical and biological environments of the slope seas and coastal oceans, which are major contributors to the global primary production. However, compared to that of eddies in the open ocean, the role of Gulf Stream warm core rings in the biophysical processes of the shelf-slope system has received less attention, and contrasting results exist. This study will elucidate the key biophysical mechanisms by investigating the biomass characteristics and the dominant physical mechanisms controlling the vertical nutrient delivery associated with Gulf Stream warm core rings. The improved understanding on nutrient dynamics from this research will contribute to the stewardship of living marine resources, and better ecosystem management. Research findings will be presented to the general public through public lectures. This project will also support the training of undergraduate students outside of oceanography through the Summer Undergraduate Research Program at the Woods Hole Oceanographic Institution.

This project investigates the physical-biological processes associated with the evolution of Gulf Stream warm core rings in the shelf-slope system of the Northwest Atlantic, with a focus on the dominant physical processes controlling vertical nutrient delivery. The research will include analyses of satellite data, historical in situ data, and numerical simulations. For better understanding of the relative importance of several mesoscale biophysical processes, the photoautotrophic biomass within the warm core rings will be characterized first using satellite observed sea surface height and chlorophyll concentration. The investigators will then conduct idealized numerical modeling experiments to identify the dominant physical processes responsible for vertical nutrient delivery including vertical mixing and vertical advection induced by frictional decay, eddy-induced Ekman pumping, and wind-sea surface temperature interaction. The findings from the idealized modeling will be further synthesized in a realistic coupled biophysical model for the Northwest Atlantic region.