Pub. date: 2008 | Online Pub. Date: April 25, 2008 | DOI: 10.4135/9781412963893 | Print ISBN: 9781412958783 | Online ISBN: 9781412963893| Publisher:SAGE Publications, Inc.About this encyclopedia
THE EKMAN LAYER (EL) is a boundary near-surface layer in the low troposphere and upper ocean, in which the vertical turbulent friction plays a crucial role in the balance of governing forces. Ekman drift is to the right of the wind in the Northern Hemisphere, which causes upwelling along the equator and certain coasts. As Ekman showed in his classic paper, the basic steady balance within EL (in the ocean where depth can be considered infinite) occurs between vertical friction and the Coriolis force. Such balance leads to the generation of the Ekman spiral of drift current (wind), that is the turning and weakening of the Ekman current (or wind) to the depth (upper boundary of Ekman layer in the atmosphere). The vector of the Ekman current (wind) is rotating clockwise/coun-terclockwise to the depth (in the atmospheric boundary layer) in the Northern/Southern Hemisphere. The angle between vectors of surface Ekman ...