While bowlturner's answer provides a list of processes to work with, I think that, since this is about worldbuilding, there should be some technique in applying all of these possibilities in a practical way. Practical means, since we're not talking about software explicitly here, possible to do ...

Here is a bit of math showing what you are up against. we are ignoring wind resistance. If we want to see how fast that water has to be moving to reach 1 mile in height, we pull out the following equation... SQRT(-2ad+finalV) = initialV Plug in the values for acceleration of gravity, final ve...

The 10% conversion efficiency mentioned in other answers is a decent rule of thumb — there's a lot of variation in the real world, but if you assume that the total prey biomass equals somewhere around 10 times the total predator biomass, you'll get a fairly plausible-looking food chain. Tim B ma...

The concept you should look into is popularly known as The Goldilocks Zone. What it boils down to (no pun intended) is a formula that tells you what is the possible range of orbital radii where liquid water can naturally occur, and thus a planet where water is present can support life. You can fi...