Langmuir mixing effects on global climate: WAVEWATCH III in CESM

•A third generation wave model has been incorporated into a global climate model.•Langmuir mixing is parameterized empirically based on large eddy simulations.•Wind-wave misalignment and Stokes drift penetration depth are considered.•Mixed layer depth is deepened and improved, especially in the Southern Ocean.•Ventilation and subsurface temperature are improved globally.