Low-frequency motions on the scotian shelf and slope

Abstract

An examination of current-mete r data gathered in 1967/68 on the continental shelf and slope off Nova Scotia has shown that meteorological forcing is an important source of energy. The response of currents to wind forcing is concentrated in a frequency band of 2.5 to 7 days. Daily mean currents of up to 25 cm/s appear to be associated with wind-stress events. The highest correlations between wind and current are for the alongshore components of these variables. Wind-induced currents may have been responsible for an intrusion of slope water onto the shelf which was observed in hydrographic sections from October and December 1968. Long data series (up to 167 days) formed by patching together shorter records demonstrate the existence of distinct low-frequency variability at periods greater than 10 days. Some aspects of these motions suggest the presence of topographic Rossby waves on the shelf and slope. However, spatial and temporal coverage of data are not sufficient to define the sources of this variability. © Taylor & Francis Group, LLC.