Acoustic propagation effects from saline intrusions across the shelfbreak front off the New Jersey coast in summer.
Arthur E. Newhall, Ying-Tsong Lin, James F. Lynch, Timothy F. Duda, Glen G. Gawarkiewicz, and John A. Colosi

     In the summer of 2006, the multi-task, interdisciplinary Shallow Water 2006 (SW06) experiment was conducted on the continental shelf and shelfbreak regions off the New Jersey coast. During SW06 during the shelfbreak front variability was clearly characterized by combined measurements of conductivity-temperature-depth casts, long-period (5 weeks) and quick sampling oceanographic sensor moorings, and surveys with a Scanfish, a ship-towed undulating vehicle carrying multiple sensors. this data set indicates that the slope water penetrated onto the shelf via neutrally buoyant intrusions. Due to the higher temperature and salinity, these frontal intrusions, seen as thin layers near the seasonal pycnocline, increased the local sound speed and accounted for variations in acoustic propagation. In this paper we will use field data and PE numerical acoustic simulations to study the impact of these frontal intrusions. Specific examples on the creation of vertical acoustic double ducting and horizontal ducting formed by these intrusions and their modulation by linear internal waves are discussed. [Work is supported by the Office of Naval Research.]


Back to the WHOI SW06 home


WHOI logo    © Woods Hole Oceanographic Institution
                        © University of Washington
University of Washington Seal
             Last updated May 2010

ONR logo