A two-dimensional, numerical circulation model is used to study the re
sponse of a stratified, f-plane ocean current to wind stress forcing a
t the surface. Nonhydrostatic, primitive equations are integrated on a
3 m vertical and 400 m horizontal grid in a periodic domain perpendic
ular to the ocean current. Initially, a geostrophically balanced curre
nt [V(i)(x, z)] with a maximum Rossby number of 0.16-0.8 is maintained
against horizontal and vertical diffusion by a body force. A spatiall
y uniform wind is applied along and across this jet. A secondary circu
lation is created as a result of the nonlinear interaction between the
jet and wind-driven flow in the Ekman layer. We present results from
seven numerical experiments. When the wind blows in the direction of t
he jet (against the jct), a narrow upwelling (downwelling) area and br
oad downwelling (upwelling) area are formed. This secondary circulatio
n pattern extends well below the mixed layer. When the wind blows perp
endicular to the jet, the secondary circulation does not extend below
the mixed layer. The fully nonlinear secondary circulation is 50% weak
er than the circulation produced by the semi-linearized calculation ar
ound the basic state, V(i). Near-inertial fluctuations appear and are
confined to the negative relative vorticity side of the circulation (d
VBAR/dx < 0). The time-averaged vertical velocity can be as high as 1.
5 m/day with a wind stress of 1 dyne/cm2 over a jct and a maximum Ross
by number of 0.16. The magnitude of the vertical circulation in this s
ymmetric basic state is dependent on the Rossby number and the horizon
tal and vertical mixing coefficients.