Convection and mixing over topography
-------------------------------------


Dense plumes generated by localized cooling on the continental shelf of the
ocean may be influenced by rotation when the deformation radius is smaller
than the width of the cooling region. Rather than gravity plumes, the
mechanism for moving dense fluid down the shelf is then through geostrophic
eddies. The simulation shown in :numref:`fig_convect_and_topo`
(blue is cold dense fluid, red is
warmer, lighter fluid) employs the non-hydrostatic capability of MITgcm to
trigger convection by surface cooling. The cold, dense water falls down the
slope but is deflected along the slope by rotation. It is found that
entrainment in the vertical plane is reduced when rotational control is
strong, and replaced by lateral entrainment due to the baroclinic
instability of the along-slope current.

  .. figure:: figs/plume.png
    :width: 70%
    :align: center
    :alt: Non-hydrostatic plume over a shelf
    :name: fig_convect_and_topo

    MITgcm run in a non-hydrostatic configuration to study convection over a slope.

