Microconvection effects at double-diffusive gradient zone boundaries

Microconvection in double-diffusive gradient zones is predicted to occur near the zone boundaries because of effects of boundary undulation and temperature modulation caused by impinging thermals in adjacent convecting zones. The equations that govern convective motion in a double-diffusive horizontal slab are solved for boundary conditions that incorporate these effects. Solution of these equations predicts a weakened salinity gradient near the gradient zone boundary between the rising thermals. When the salinity gradient is too weak, instability occurs, taking the form of descending plumes, which are seen in experiments