Gulf of Maine Currents
The current patterns in the Gulf of Maine are greatly affected by the physical characteristics of the gulf and its coastline. Although currents change seasonally, here's how they generally flow:
- Cold water enters the gulf over the Scotian Shelf, Browns Bank and through the Northeast Channel.
- Once in the gulf, water flows around Nova Scotia and into the Bay of Fundy.
- The coast then deflects currents southwestward...
- ...forming the Gulf of Maine Gyre, which rotates counterclockwise, moving surface waters about 7 nautical miles per day.
- Tidal fluctuations and shallow water over Georges Bank form a secondary, clockwise-spinning gyre.
- Water leaves the gulf through the Great South Channel and over the eastern portion of Georges Bank.
It takes about three months for surface water to completely circle the Gulf of Maine. Deep waters also circulate, but much more slowly, taking about a year to complete the circuit. Freshwater river input from more than 60 rivers along the coastline contributes to circulation in the gulf, reduces salinity, transfers nutrients out over the heavier salt water and increases survival of eggs and larvae.
Physical Science – Oceanography – Ocean Current Systems
Links:
Global Ocean Currents
Woods Hole Oceanographic Institution: Abrupt Climate Change: Should we be Worried?
http://www.whoi.edu/institutes/occi/currenttopics/climatechange_wef.html
Smithsonian Ocean Planet Ocean Currents
http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/oceanography_currents_1.html
HYCOM Consortium Ocean Surface Currents
http://oceancurrents.rsmas.miami.edu/
Ocean Surface Topography from Space (JPL) Science Data Gallery
http://topex-www.jpl.nasa.gov/gallery/science.html
Weather Phenomenon and Elements: Wind-Driven Ocean Currents
http://www.islandnet.com/~see/weather/elements/shoes.htm
Dartmouth Circulation Models for GOM (extremely technical)
http://www-nml.dartmouth.edu/circmods/gom.html