  Probability density functions and conditional averages of velocity gradients
derived from upper ocean observations are compared with results from forced
simulations of the two-dimensional Navier-Stokes equations. Ocean data are
derived from TOPEX satellite altimeter measurements. The simulations use rapid
forcing on large scales, characteristic of surface winds. The probability
distributions of transverse velocity derivatives from the ocean observations
agree with the forced simulations, though they differ from unforced simulations
reported elsewhere. The distribution and cross-correlation of velocity
derivatives provide clear evidence that large coherent eddies play only a minor
role in generating the observed statistics.
