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SIMULATIONS OF OCEAN MIXED LAYERS WITHSTOCHASTIC SURFACE FORCING

PETER SULLIVAN

NATIONAL CENTER FOR ATMOSPHERIC RESEARCH

Collaborators:

James McWilliams (UCLA)

Ken Melville (SIO)

``… At wind speeds above about 8m/s, momentum isbelieved to be transferred between air and waterprincipally through waves and not by viscous drag onthe surface.

… Momentum and kinetic energy is delivered to theunderlying water through the intermediary of wavesamplified and dissipated locally…”

Mark Donelan (1998)

WINDS TO WAVES TO CURRENTS

Hurricane Isabel CBLAST Photo courtesy M.Hurricane Isabel CBLAST Photo courtesy M.Montgomery (CSU)Montgomery (CSU)

HIGH WIND SURFACE DYNAMICSHIGH WIND SURFACE DYNAMICSWAVE BREAKING AND LANGMUIR CIRCULATIONSWAVE BREAKING AND LANGMUIR CIRCULATIONS

Great Salt Lake Photo courtesy S. Great Salt Lake Photo courtesy S. MonismithMonismith(Stanford)(Stanford)

Intermittent fluxes of momentumand energy

Wave-averaged effects

PDF OF BREAKING FOR VARYING WIND SPEED

( .. ) - Stokes terms

( .. ) - Breaker terms

Momentum

SGS e

Density

LES OF OCEAN PBL WITH WAVE EFFECTSPARTICLE PATHS

PARTICLE PATHS OVERLAYING VORTICITY CONTOURS

STOCHASTIC LES WITH WAVE BREAKING:W VISUALIZATION IN Z PLANES AND 3D STRUCTURES

Ring vortices

Wave energyWind input

Non-linear waveinteractions

Dissipation fromwave breaking

Before Bonnie

After Bonnie... .

... ..

SST Variations& Ocean Mixing

Shuyi Chen, RSMAS

LANGMUIRCIRCULATIONS

GREAT SALT LAKE

COURTESY S.MONISMITH