Sketch of the circulation around regions of high pressure (high sea level) and low pressure (low sea level) in the open ocean. The current circulates around the highs and lows, following the lines of constant pressure (isobars, shown in black). Circulation around regions of low pressure is called cyclonic, circulation around regions of high pressure is called anti-cyclonic. Note that the sense of rotation changes with the hemispheres.
© 2000 Matthias Tomczak.