Flood Risk and Vulnerability Analysis Project - Atlantic Climate ...

and relatively fresh water from the Arctic south along the continental shelf and slope of Labrador
and Newfoundland. The Gulf Stream brings warm and salty water north from the Gulf of Mexico
along the continental slope of North America. It veers to the northeast away from the continent
at Cape Hatteras and flows eastward just south of the Grand Banks, occasionally moving north
onto their southern edge. The presence of the air masses over the two currents, moist and cold
over the Labrador Current, moist and warm over the Gulf Stream, directly affects the
temperature, precipitation and formation of fog, especially on the eastern coastal region of the
island of Newfoundland.
Figure 3-23. Major Ocean Currents affecting Newfoundland and
Labrador (from Wikipedia).
The Gulf Stream is also the warm surface limb of the Meridional Overturning Circulation (MOC),
illustrated in Figure 3-24. It brings warm salty water to northern regions where it loses heat to
the colder atmosphere, mixes with cold arctic water and sinks to the bottom (deep convection in
the Greenland Sea and Labrador Sea) as it encounters cold dense water flowing south as the
lower limb of the MOC. The MOC is a very important process that efficiently redistributes the
excess heat from tropical regions to heat deprived northern regions, thus playing a primary role
in maintaining the earth‟s climate balance.
The climate of Newfoundland is also affected by four major atmospheric or coupled oceanatmosphere
phenomena: the North Atlantic Oscillation (NAO), the Arctic Oscillation (AO), the
Atlantic Multi-decadal Oscillation (AMO) and, remotely from the Pacific Ocean, the El Nino
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