Richard Aiken wrote:
 > Yes. But given enough data points and computing power,
 > weather should also be fairly predictable.

Nope. You end up with a probability distribution for whatever parameters
you can measure.
You can't say "next Thursday Bitburg will have a temperature min/max of
x to y with/without rain".

There is also a chance of unwanted extreme effects!
Blame Edward Lorenz, the meteorologist and mathematician who is a key
figure in the history of chaos theory.

 >> Congratulations! You just invented a tornado cannon!
 > Yeah. I believe it's called a Planetary Defense Meson Gun.
 > Or maybe a Mahgiz Event Generator. ;)

Starship spinal mounts have a power requirement on the order of 300
gigawatts in Megatraveller, taking each High Guard energy point as
250MW. So with 50% efficiency and one 'shot' every 20 minute combat
turn, that's an energy output of 180 petajoules or about 45 megatons of
TNT equivalent.

So they are already in tornado cannon country.

The Maghiz could have been generated by a very large nuclear damper
(tweak the strong force and increase the reaction rate by at least ^4),
or attempts at mining the surface layers of a star a la David Criswell:
https://en.wikipedia.org/wiki/Star_lifting

Weather/climate control/terraforming effectors can be repurposed to
become weapons of mass destruction, given the energy scales required.

Rob O'Connor