#### Re: Can someone explain....

Just like paperwork and your desk the computation expands to fill the computer ...

Remember in computational science it is very rare that computers give exact solutions to the real physical problem. Rather approximate solutions to models of reality are what you get, and the game is to get the most accurate solution to the best model that you can solve. 10 years ago the computational facilities could solve certain models to a certain accuracy. 10 years of improvement allows

a) more accurate and complex models to be solved

b) already used models to be solved at higher accuracy

c) a mixture of both

I don't know what kind of models they are solving, but for b) it might be as simple as resolving features in the solution at 1km instead of 5km (c.f. weather forecasting). And the higher accuracy in this case really is very much better - I really don't want these things going kablooey unrequested, and like the poster above I'm interested that this is done from every viewpoint AND with the best accuracy that is currently feasible.