|Title||Approximate Stokes drift profiles in deep water|
|Publication Type||Technical memorandum|
|Secondary Title||ECMWF Technical Memorandum|
|Authors||Breivik, Ø, Janssen, PAEM, Bidlot, J-R|
A new approximation to the Stokes drift velocity profile is proposed as an alternative to themonochromatic profile. Comparisons with parametric spectra and full two-dimensional wave spectra from the ERA-Interim reanalysis in the North Atlantic show significant improvement over the monochromatic profile even for complex sea states. The profile gives both a closer match and a more correct shear compared to the monochromatic profile. This has implications for ocean circulation since the Coriolis-Stokes force depends on the magnitude and direction of the Stokes drift profile and Langmuir turbulence depends sensitively on the shear of the profile. The proposed profile comes at no added numerical cost and relies on the same two parameters, viz the Stokes transport and the surface Stokes drift velocity.