Dynamics of Destratification in the Severn River Estuary
Abstract
As part of an effort to study the hydrodynamic behavior of the Severn River estuary, a mooring with several oceanographic sensors was deployed near the mouth of the river during the autumn of 1995. This mooring had two current meters located at depths of 2.3 and 4.7 meters which took readings of salinity, temperature, and current velocity. Simultaneous wind speed and direction data were taken from the top of Michelson Hall. The purpose of this project was to document the circulatory pattern of the Severn estuary and determine how the fall destratification occurs. The time series provided by the instruments from September to December of 1995 were low pass (LLP) filtered in order to isolate the non-tidal components. Based on the non-tidal salinity and current data, it was determined that the Severn River estuary falls into the partially-mixed (2a) category according to the Hansen and Rattray criteria. The gradient Richardson Number was also calculated for the observation period. It is concluded that once the water column shows very low dynamic stability induced by surface cooling, a strong wind event can trigger the overturning of the column. Upon wind relaxation, stratified conditions may resume. The coupling between local wind forcing and subtidal flow was most significant at a period of 5 days.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 07, 1997
- Accession Number
- ADA418475
Entities
People
- Christopher S. Irwin
Organizations
- United States Naval Academy