|The Gulf Stream is the fastest ocean current in the world with peak velocities near 2m/s. Shown to the left are velocity profiles across the Gulf Stream at the Straits of Florida and Cape Hatteras. In both sections the Gulf Stream is flowing into the page.
As the velocity profiles indicate, the maximum velocities are confined to the top 200 meters of the water column. Velocity decreases with depth, and the flow below 1000 meters is usually less than 10 cm/s.
|Transport and Velocity figure from: Regional Oceanography: an Introduction by M. Tomczak and S. J. Godfrey|
|The figure below depicts the surface velocity of the North Atlantic during September 2000. Gulf Stream velocity fields are derived from near-realtime radar altimeter data measured from a satellite. The velocities of the currents are represented by colors as well as by arrows. Brighter colors indicate higher velocities. As the color bar at the bottom shows, velocities are in the range of 0 to 1 m/s (meters per second), which corresponds roughly to 0 to 2 knots (nautical miles per hour). The size of the arrows also refer to the magnitude of the velocity, an arrow of 1 m/s (approx. 2 knots) is drawn in the lower right corner, next to the color bar. The directions in which the arrows point is the direction of the current. Thus, an arrow pointing to the right indicates an eastward flow.
The highest velocities are observed both in the Gulf Stream current and south of the current in eddies that formed from the Gulf Stream. The formation of these eddies will be discussed later.
|Image courtesy of Delft Institute for Earth Oriented Space Research|
|The width of the Gulf Stream can also be seen by looking at a temperature or density section. In this temperature section, west is to the left and east is to the right, so the Gulf Steam is flowing into the page.
Sloping isotherms (or isopycnals on a density section) indicate where the current is flowing. The isopycnals are horizontal on both sides of the Gulf Stream, indicating no flow in these regions.
A corresponding density section is shown below.