Sublithospheric Small Scale Convection

Initially, the box has uniform temperature of 1 everywhere. With surface temperature is fixed at 0 as boundary condition, the box cools with the time. As the box cools, the top thermal boundary layer thickens with time. Depending on activation energy and mantle viscosity, the thickened top thermal boundary layer eventually goes unstable. The panel on the top shows how surface heat flux evolves with time and how it compares with the cooling half-space model prediction (in dashed line). The panel on the right shows how the horizontally averaged temperature vs depth varies with time and it compares with the cooling half-space model prediction (in dashed line).