  We present a set of idealised numerical experiments of a solstitial
aquaplanet ocean and examine the thermodynamic and dynamic implications of
surface gravity waves (SGWs) upon its mean state. The aquaplanet's oceanic
circulation is dominated by an equatorial zonal jet and four Ekman driven
meridional overturning circulation (MOC) cells aligned with the westerly
atmospheric jet streams and easterly trade winds in both hemispheres. Including
SGW parameterization (representing modulations of air-sea momentum fluxes,
Langmuir circulation and Stokes-Coriolis force) increases mixed layer vertical
momentum diffusivity by approx. 40% and dampens surface momentum fluxes by
approx. 4%. The correspondingly dampened MOC impacts the oceanic density
structure to 1 km depth by lessening the large-scale advective transports of
heat and salt, freshening the equatorial latitudes (where evaporation minus
precipitation [E-P] is negative) and increasing salinity in the subtropics
(where E-P is positive) by approx. 1%. The midlatitude pycnocline in both
hemispheres is deepened by the inclusion of SGWs. Including SGWs into the
aquaplanet ocean model acts to increase mixed layer depth by approx. 10% (up to
20% in the wintertime in midlatitudes), decrease vertical shear in the upper
200 m and alter local midlatitude buoyancy frequency. Generally, the impacts of
SGWs upon the aquaplanet ocean are found to be consistent across cooler and
warmer climates. We suggest that the implications of these simulations could be
relevant to understanding future projections of SGW climate, exoplanetary
oceans, and the dynamics of the Southern Ocean mixed layer.
