So this is what a spreadsheet version of that first

problem might look like, with some parameter values

up at the top that you can change interactively, and

some time steps down below, sort of down through here.

And this is a plot of planetary temperature as a function of time,

and the different symbols there are the time steps.

If we look at that as a Python script,

you can see it's just a short little thing there.

We can run that Python script, and

it does the same thing as the Excel spreadsheet does.

Other Python tricks that we will do in this class include an ice sheet.

So, here, we're taking time steps and

plotting the elevation of an ice sheet as a function of lateral distance.

So there's snow falling everywhere throughout the domain,

and the values at the edges are held at 0 as a boundary condition.

And eventually it reaches a steady state, where the inflow and

the outflow of ice at any grid cell reaches balance.

And that's when the elevation

of the thing stops changing.

The red dot in the middle here,

box was sort of a tower of water at the initial condition.

And so the water started flowing out and

it made waves that went all over the place.

But now, after a few rotational periods, the flow has found this equilibrium where

it's going around and around the tower of water instead of just flowing out from it.

You can see these sorts of rings, so

these are the basic equations of motion that govern fluid flow.

Anyway, welcome to the class, and I hope you find it of use.