World Wide Web Site
created by
Midshipman Pamela Phillips, US Naval Academy
and
Richard Gasparovic, Applied Physics Laboratory, Johns Hopkins
University
The Gulf Stream forms the western boundary of the North
Atlantic gyre, around which the currents flow in a clockwise
direction. The Gulf Stream system begins on the eastern side of the
Gulf of Mexico, flows through the Florida Straits, and then along the
southeastern coast of the United States to Cape Hatteras, North
Carolina. From Cape Hatteras, the Stream flows eastward away from the
coast, into deeper water as it proceeds toward Europe. Although its
path is lengthy and has many segments, the Gulf Stream is considered
to be a single current system.
The Gulf Stream is typically 80 to 150 kilometers wide and
extends to a depth of about 800 to 1200 meters. The fastest current
in the Gulf Stream is near the surface and the speed decreases with
depth. The maximum current speed is usually observed to be about 2
m/sec. There is a very distinct vertical temperature structure within
the Gulf Stream. A permanent thermocline exists beneath the Stream
sloping upward from the right to the left side of the current. This
thermocline separates the warm water of the Gulf Steam from the cold
Slope water and the boundary is often referred to as the Cold Wall or
North Wall. The North Wall makes it easy to identify the position of
the Gulf Stream in satellite infrared images by observing the strong
sea surface temperature gradient.