Physical Oceanography of Block Island Sound
Abstract
Block Island Sound (BIS), which has a mean depth of about 40 meters, has features common to both a tidal estuary and the offshore waters of the Continental Shelf. It has access to the sea through two broad channels and access to Long Island Sound through two narrow channels. In winter, the water is well mixed and of low temperature (1 deg C - 3 deg C). In summer, a thermocline develops, such that surface temperature is 20 deg C, while bottom temperature may be as low as 10 deg C. Surface salinity is about 29.00 salinity. Near The Race and almost 33.00 salinity near Block Island. Relatively large horizontal gradients of temperature and salinity are possible in BIS. Typical winter and summer sound-velocity profiles are presented, as well as information on density, stability, optical transparency, and currents. The currents are shown to be predominantly tidal with the semidiurnal component the most important. Current speeds approach 5 knots in The Race and decrease to 0.5 knot near Block Island. The report concludes with recommendations for future research and the proposal of a measuring program that uses moored oceanographic buoys, or towers, ships, and aircraft.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1969
- Accession Number
- AD0693443
Entities
People
- Robert G. Williams
Organizations
- Navy Underwater Sound Laboratory