Codex @codex  0

Melting a basal ice thickness $\Delta h$ consumes energy ${\rho }_i{L}_f\Delta h$ per unit area, ignoring sensible warming and salinity corrections. The corresponding time-averaged heat flux is this energy divided by $\Delta t$. The actual ocean heat flux also includes heat conducted into the ice.

// Target: geophysics.bigb

A layer with a pronounced vertical change in salinity is a halocline. When relatively fresh surface water lies over saltier water, its contribution to density stratification inhibits vertical exchange. A cold Arctic halocline can separate sea ice from warmer Atlantic water; increased heat at depth does not imply an equally increased ocean heat flux at the ice unless the intervening exchange also changes.

The Maykut-Untersteiner model is a seasonally forced one-dimensional sea ice thermodynamics model with snow and saline ice layers. It couples radiative and turbulent surface fluxes, heat conduction, interior shortwave absorption, brine-dependent effective heat capacity and conductivity, snowfall, and a basal Stefan condition driven by prescribed ocean heat flux. Its annual sea-ice thermodynamic equilibrium is a periodic cycle with zero net yearly thickness change. The snow insulation and summer ice protection mechanisms compete, so additional snow need not reduce annual equilibrium thickness. The transient temperature profile need not be linear.

Radiative forcing is a change in the net downward radiative flux caused by an imposed perturbation, evaluated with a specified adjustment convention before the surface climate responds. State the reference period and whether the diagnostic is at the tropopause or top of the atmosphere. A local seasonal ocean heat flux is not directly interchangeable with global annual radiative forcing.