Abstract
Though thermohaline staircases exist in a large region of the Arctic,
the interactions of such staircases with shear and turbulence are still
largely unexplored. We perform a series of two- and three-dimensional
simulations with and without shear and demonstrate the capacity of shear
to both form and disrupt Arctic staircases. Both isotropic shear and
unidirectional oscillating shear are considered. Shear is shown to
disrupt staircases when the Richardson number falls below 1/4. For
isotropic shear, this process works by breaking down layers
individually, which leads to the gradual merging of layers, whereas the
unidirectional shear tends to break down interfaces more evenly. For
weaker shear (Richardson numbers greater than 2), the spontaneous
development of layers is observed.