of the theoretical kind

in addition to experiments and observations, i also develop and use models of ice behaviour for understanding planetary evolution.

for my fellowship, i am applying the experimental results to thermophysical and mechanical models of permafrost on Mars. using 1d and 2d thermodynamical models, i determine the rate of heat and mass transfer from an icy layer to the atmosphere under different conditions, and the formation of subsurface aquifers. these models are dependent on the properties of the solid (ground), liquid (porous water) and gaseous (atmosphere) phases present, with the diffusion coefficient of water of utmost importance. i will also use both analytical and finite-element methods to model the mechanical behaviour of ice on Mars, to study the long-term response of the surface and near-subsurface to different stresses and conditions.

for my postdoc, i spent a fair amount of time modelling the behaviour of icy moons. working closely with dominic fortes, i worked on the possibility of mud volcanoes on titan, predicted explosive volcanism to be widespread on titan, and determined whether an ammonium sulfate ocean can survive inside titan to the present day. all these papers can be found on my publications page.

figure from grindrod et al (2008) , looking at whether an ammonium sulfate ocean can survive inside titan to the present day. effect of initial temperatures on the persistence of the ocean for different scaling laws. for stagnant lid scaling law, radii of ocean boundaries for different initial core temperatures in K (a) and different initial crustal temperatures in K (b). for simple isoviscous scaling law, radii of ocean boundaries for different initial core temperatures in K (c) and different initial crustal temperatures in K (d). all other parameters are the same as in the nominal case.

in terms of parameterised models, i had a few different projects on the go, all with the aim of understanding the thermal evolution of icy moons. these include: (1) incorporating phase changes, (2) having dynamic material layers, (3) having an equation of state controlled density, and (4) the survivability of a generic ocean layer. work on these continues, but if you want to get a good base for parameterised models then look at solomatov (1995) for the scaling laws, and schubert et al. (2001) for a good description of the method.

other projects that i am still working on include modelling the mass-radius relationship and thermal evolution of extrasolar planets and moons, and also modelling possible gypsum and ice diapirs on mars.

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