Inter-Disciplinary Shelfbreak Procesesses: Observations from the R/V Neil Armstrong

Glen Gawarkiewicz, Physical Oceanography
Daniel Torres, Physical Oceanography
Weifeng (Gordon) Zhang, Applied Ocean Physics & Engineering


2016 COI Funded Project


The continental shelf and slope south of New England have recently been undergoing significant changes, including warming and increasing influence of Gulf Stream interactions.  In order to examine the shelfbreak frontal system, we are participating in the R/V Neil Armstrong Science Verification Cruise VI from June 17- 23, 2016 to test new multi-frequency acoustic systems on the ship.  The PIs comprise the physical oceanography component of this cruise and will be collecting CTD, shipboard ADCP, and lowered ADCP data to determine the structure and position of the shelfbreak front, as well as characteristics of the associated frontal flow.  The goal of this project is to use these data together with other available measurements in the region to understand how the frontal system affects the distribution of marine species in the biologically productive shelfbreak region.   Wepropose to analyze the data collected on this cruise, compare them to other recent data including those collected from the Joint Program Orientation cruises, and then relate the velocity, temperature, salinity, and density data to the distribution and abundance of organisms collected from video plankton recorder profiles, net tows, and acoustic backscatter measured by the new EK80 system mounted on the ship (effort led by Gareth Lawson).  In addition, as the acoustic backscatter intensity measured by the lowered ADCP is highly related to the abundance of organisms in the water column, it will be directly compared to the net tow and EK80 data.  The data collected on this cruise will also be compared to concurrent OOI Pioneer Array data to cross-compare and gain further insight into the shelfbreak processes observed on the cruise.  The results will help us understand how the recent physical changes in the New England shelf and shelfbreak region may have been influencing the local ecosystem.