Patrick Heimbach is a research scientist in physical oceanography at MIT, and James Hack heads up climate modeling at the National Center for Atmospheric Research in Boulder, Colo. Both scientists use their own organizations' computer systems, as well as those at supercomputer centers around the U.S.

What are you working on at MIT?

Heimbach: We are trying to see if we can simulate, if we can understand, what the ocean has been doing over the last couple of decades. Are we heading toward a warmer world? Is [warming due to] internal variability of the [oceanic and atmospheric] system, or is there something we are doing to the system?

Do you have the computational power to do that?

Heimbach: What we ultimately would like to run we can't currently fit on any computer. We would need on the order of 20,000 processors, and probably two orders of magnitude faster processors. Each supercomputer center allocates a certain amount of computing time to a specific group. So we have to size down the problem we are addressing for that specific machine.