Hughes, GrahamGriffiths, RossMullarney, JPeterson, William H2015-12-080022-1120http://hdl.handle.net/1885/34990We present a simple flow model and solution to describe 'horizontal convection' driven by a gradient of temperature or heat flux along one horizontal boundary of a rectangular box. Following laboratory observations of the steady-state convection, the model is based on a localized vertical turbulent plume from a line or point source that is located anywhere within the area of the box and that maintains a stably stratified interior. In contrast to the 'filling box' process, the convective circulation involves vertical diffusion in the interior and a stabilizing buoyancy flux distributed over the horizontal boundary. The stabilizing flux forces the density distribution to reach a steady state. The model predictions compare well with previous laboratory data and numerical solutions. In the case of a point source for the plume (the case which best mimics the localized sinking in the large-scale ocean overturning) the thermal boundary layer is much thicker than that given by the two-dimensional boundary layer scaling of H. T. Rossby (Tellus, vol. 50, 1965, p. 242).Keywords: Boundary layers; Buoyancy; Diffusion; Heat flux; Mathematical models; Numerical methods; Thermal gradients; Turbulence; Convective circulation; Horizontal convection; Rayleigh number; Heat convection; Boundary layers; Buoyancy; Diffusion; Heat convection;200710.1017/S00221120070056302015-12-08