In the spirit of “All stable processes we shall predict, all unstable processes we shall control.” I was thinking about how you would control the weather and earthquakes. One big problem for both of these is convection. For example, earthquakes are powered by hot material from inside the earth being transported out. I noticed my day-to-day intuition had been really confused by convection in solids. Intuitively, moving mass around feels much more inefficient than conduction. I still don’t have great intuition for this, but one thing that helped was learning about the Rayleigh number (not to be confused with Reynolds number) which quantifies in which regimes convection rather than conduction dominates. Intuitively, the problem with conduction is that it works best if there are large energy distances locally, but the longer the distance the heat has to travel, the flatter the local heat gradient is going to be. Convection moves things in bulk, which works better with more volume. Heat transfer is so slow inside the earth, a large part of earths internal heat is still left over from the potential energy released by its formation. So if heat wasn’t moved by all of the mantle collectively moving centimetres a year, even less heat would escape.
In the spirit of “All stable processes we shall predict, all unstable processes we shall control.” I was thinking about how you would control the weather and earthquakes. One big problem for both of these is convection. For example, earthquakes are powered by hot material from inside the earth being transported out. I noticed my day-to-day intuition had been really confused by convection in solids. Intuitively, moving mass around feels much more inefficient than conduction. I still don’t have great intuition for this, but one thing that helped was learning about the Rayleigh number (not to be confused with Reynolds number) which quantifies in which regimes convection rather than conduction dominates. Intuitively, the problem with conduction is that it works best if there are large energy distances locally, but the longer the distance the heat has to travel, the flatter the local heat gradient is going to be. Convection moves things in bulk, which works better with more volume. Heat transfer is so slow inside the earth, a large part of earths internal heat is still left over from the potential energy released by its formation. So if heat wasn’t moved by all of the mantle collectively moving centimetres a year, even less heat would escape.