Eddy Structure of the North Pacific Ocean

Abstract

The North Pacific Ocean is nearly twice as large as the North Atlantic; indeed, in the lower latitudes the Pacific’s east-west dimension is about three times that of the Atlantic. Yet both oceans are forced by roughly similar westerly winds in midlatitude, which separate the easterly trade winds to the south from the polar easterlies to the north. Both oceans respond in their wind-driven circulation by forming a set of basin-wide gyres with intensified western boundary currents, the basic character of which has been known for many years. More recently, oceanographers have determined that these large-scale currents frequently develop mesoscale (50 to 500 km) instabilities which are dynamically important.