Dynamics of frontal meandering and related exchange processes at the shelfbreak south of New England

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The shelf break front is one of the most salient features of the regional oceanography of the Middle Atlantic Bight, both in terms of its physics and biology. Processes associated with the shelf break front are inherently nonlinear and exhibit variations over a broad range of spatial and temporal scales. The shelf-break frontal jet, subject to local instabilities, meanders along the shelf break and interacts with winds, continental shelf eddies and slope sea warm-core rings. The shelf-break region also has significant along- and cross-shelf fluxes of heat, salt and nutrients that are subject to modification by frontal meandering, winds and impinging warm-core rings. Despite many years of study in the region, many scientific questions related to meandering of the shelf break front, bottom boundary layer dynamics, and cross-shelf exchange remain unanswered. The primary objectives of the proposed research are to understand characteristics of the shelf-break frontal meandering south of New England, its underlying dynamics, and effects of frontal meandering and other forcing mechanisms on cross-frontal exchanges. The proposed research will consist of analysis of historical and forthcoming Pioneer Array observations and idealized numerical simulations to: reveal the formation and evolution of large amplitude shelf-break frontal meandering south of New England; diagnose characteristics of the frontal meandering; investigate the effects of frontal meandering, winds and warm-core rings on flows in the shelf-break bottom boundary layer; investigate the effects of frontal meandering, winds and warm-core rings on cross-frontal exchange; and examine the along-shelf and vertical variations of the cross-frontal exchange. Intellectual merit: Numerical simulations will be used in conjunction with analysis of historical and forthcoming observations to address fundamental scientific questions concerning dynamics of frontal meandering at the New England shelf break and effects of frontal meandering and other forces on cross-frontal exchange. Broader impacts: Better understanding of meanders of the shelf break front and cross-frontal exchange will provide the physical background for studies of biological productivity and contaminant dispersal at the shelf break. This project has implications for commercial fisheries and marine conservation. Results of this project will be communicated to general public and K- 12 students, and also used for future outreach effort providing informal education materials including video and multi-media presentations.