Scotian Shelf and Scotian Coastal Shelf

In an earlier version of this map we did not distinguish between these two areas which we now divide at the 100 m isobath. The following description applies to both areas combined.

Overview
The Scotian Shelf is a very broad coastal shelf that extends from the coast of Nova Scotia to the edge of the continental slope. Approximately 60 miles wide at its southern extreme, near the Northeast Channel, the shelf broadens as it trends towards the northeast. Currents are characterized by a year-round, near-shore flow from the northeast to the southwest; it is known as the Nova Scotia Current. Influenced by the Gulf Stream to the south and the Labrador Current to the north, the waters of the Scotian Shelf support a wide variety of organisms. Tidal currents, seasonal cooling and upwelling related to bathymetric features return nutrients to sun-lit surface waters and contribute to the high productivity of shelf waters. The Scotian Shelf supports commercial fisheries for groundfish, lobsters and other species.3

Surface area
14,084 mi2

Depth
Intertidal to ~200 m

Bathymetry including key features
The bathymetry of the Scotian Shelf is marked by a broad trough, punctuated by a series of small, isolated banks, that runs the length of the shelf between the shallower coastal area and a series of large banks that mark the outer edge of the shelf. The most prominent of these large banks is Brown’s Bank which forms the western terminus of the Scotian Shelf. 4,5

Substrate
The substrate of the Scotian Shelf varies according to its bathymetry: the banks are comprised of coarser sediments, such as sand and gravel, while the basins are characterized by finer-grained sediments such as clay. Boulders that dropped from the bottoms of melting glaciers occur occasionally. 6

Relationship to large-scale circulatory patterns of the Gulf of Maine
Currents flowing southwestwardly along the Scotian Shelf flow around the tip of Nova Scotia and contribute to the establishment of the counterclockwise gyre that characterizes currents in the Gulf of Maine. 7,8

Information on average (seasonal/annual) oceanographic conditions
On average, currents flow southwestardly along the Scotian Shelf. Derived from a mixture of St. Lawrence River outflow and Labrador currents, Scotian Shelf currents are are relatively fresh and cool. In the summer, shelf waters are stratified. Mixing occurs in the winter as surface waters cool and sink. Smaller scale oceanographic features, such as estuarine circulation, coastal upwelling, tidal fronts and shelf-break fronts, contribute to mixing of the shelf waters. 9

1 Cok, et al., 1965
2 Nova Scotia Museam of Natural History, Undateda.
3 Nova Scotia Departments of Agriculture and Fisheries and Aquaculture, Undated
4 Nova Scotia Museam of Natural History, Undatedc.
5 Kostylev, et al., 2001
6 Nova Scotia Museam of Natural History, Undatede.
7 Pettigrew, et al., 2005.
8 Xue, et al., 2000.
9 Nova Scotia Museum of Natural History, Undatedb.