Re: Mother nature
Wed, 15 Sep 1999 10:57:42 -0700

David Lubkin, <>, writes:
> Given quadrillions of sensors and lots of computational power, how far in
> advance can we predict severe or extreme weather and seismic events?
> How can we divert or dissipate them?

One possibility is chaotic control. Chaotic systems like the weather can theoretically be controlled using very small power inputs. You do need a lot of computer power and sensors though. The idea is that you have a desired outcome, and you run your predictions to see if it is in the range of possible outcomes from the current state. You continue to adjust your inputs to try to keep the desired outcome roughly in the middle of the range of possible outputs.

It is basically the same process used to keep your car in the middle of the lane. The car's path is like a chaotic process, in that a small divergence in initial conditions (steering wheel position) leads to a large change in where the car ends up after a while. But you can keep it in the road by making tiny adjustments to the steering wheel.

I don't have a clear understanding of what level of sensing and prediction is necessary to make this work. At a minimum you would need sensors at the level of the kinds of changes you were going to make, and models which can work from disturbances at that level up to the level of the weather changes you want to make.