Undergraduate Research and Creativity

URECA

2006-2007

Short Term Oscillations Over the Northeastern Seaboard
in Observations and Storm Surge Models

Alexander Mintz and Malcolm J. Bowman
Stony Brook Storm Surge Research Group
Marine Sciences Research Center
Stony Brook University

The Stony Brook Storm Surge Research Group (SBSS) is developing a coupled ocean atmospheric storm surge forecasting model for the northeastern seaboard, with emphasis on Metropolitan New York, New Jersey and Long Island. Both the model predictions and observations sometimes exhibit a "ringing" (T~6 hours), whose period is noticeably independent from tidal oscillations (T~12.42 hours) and whose origins are being investigated. We are investigating possible sources, both natural (e.g., wind gusts) and numerical (e.g., errors in wind stress formulation). Observed ringing in continental shelf seiching is most likely produced by sudden changes in wind velocity and/or direction (e.g., passage of a low pressure system). In such cases, this ringing is present in both observations and model predictions. However, on many occasions the models exhibit ringing without the presence of impulsive wind forcing. Such artifacts compromise the accuracy of the model and lead to large errors between predicted and actual (observed) storm surge. This investigation will hopefully identify the source of the ringing (e.g., inadequate boundary conditions, extreme bathymetric gradients, and errors in ingesting atmospheric wind predictions).