in Context the SCotian Shelf - COINAtlantic

Figure 2: Detailed surface circulation on the Scotian Shelf. (Source: adapted from C.Hannah in Breeze et al 2002).
be attributed to two main causes: a change in the
volume of water in the ocean and changes caused
by the sinking or rising of land. Changes in the
volume of water may be due to rising or lowering
of temperatures, leading to the thermal expansion
or contraction of water, as well as changes in the
amount of water stored in polar ice and on land
in glaciers, lakes, rivers, and other reservoirs. In
Atlantic Canada, the land is still rising and sinking in
response to the retreat of the last glacier more than
10 000 years ago. This rising and sinking, known as
post-glacial or isostatic rebound, is causing a large
area, including Nova Scotia, to sink and thus sea
levels to rise. Overall, there is a general trend of sea
level rise on the Atlantic coast of Nova Scotia. Petrie
et al. (2009) estimated a total value of 31.9 cm/
century at Halifax, with 23 cm/century attributable
to post-glacial rebound (Tushingham and Peltier
1991 cited in Petrie et al. 2009).
2.4 OCEANOGRAPHIC
Conditions
The Scotian Shelf is most strongly influenced by three
currents: the Nova Scotia Current, the Labrador Current
and the Gulf Stream. Relatively cool, fresh waters
flow from the Gulf of St. Lawrence through the Cabot
Strait. Part of this flow turns at Cape Breton to flow
southwestward along Nova Scotia’s Atlantic coast,
while the rest of the flow continues through the Laurentian
Channel to the shelf break. There, it turns and
joins with the Labrador Current to flow southwestwards
along the shelf edge. The third major current,
the Gulf Stream, flows northeastwards. Its warmer,
saltier waters mix with the cool Labrador Current
waters over the Scotian Slope, forming a water mass
known as slope water. The slope water periodically
http://coinatlantic.ca/index.php/state-of-the-scotian-shelf
13