At the top, \b[$T(a,t)=T_0$]. Ocean water provides a cold <thermal reservoir> relative to <mantle> <temperatures>, so a fixed surface <temperature> is a useful idealization. The model does not resolve near-axis hydrothermal circulation or spatially variable bottom-water <temperatures>.

Solution

Past exam of the physics of the Earth as a Planet course of the University of Cambridge / 2013 / Paper 1 / 1 / a / i / Solution

 Solution (source code)