On Friday I was going down the M40 from London to Oxford. At Stokenchurch there is an escarpment. The top was dry, going down the hill it was pouring with rain. What seemed to have happened was that the wind wasn't strong enough to get clouds over the hill, but the slight raise was causing cooling and rain.

I wonder if that effect might be created artificially. If a steep valley ending in a hill facing towards prevailing winds is fitted with some fans, and appropriately placed shutters built, might it not be possible to build up an airstream, that because it would be rising, would condense and cause rain? It might not use too much energy if designed carefully, could use existing hydro and might be a very boring place to live because of continual rain and cloud!

OK, so that is agreed then!

These very wet places could of course be resting places for Douglas Adam's rain god, who followed a truck driver everywhere and showed his love by raining continuously!

Doh! Got story backwards!

Douglas Adams
“And as he drove on, the rainclouds dragged down the sky after him, for, though he did not know it, Rob McKenna was a Rain God. All he knew was that his working days were miserable and he had a succession of lousy holidays. All the clouds knew was that they loved him and wanted to be near him, to cherish him, and to water him.”


― Douglas Adams, So Long, and Thanks for All the Fish

https://www.goodreads.com/quotes/90592- ... d-down-the

Nice idea.
Many things going on here. Drainage winds, orographic flows, differential heating, airmass lifting cooling and condensation. Would depend totally on the specific situation whether your idea worked or not.

I am working on goeengineering at the moment with planting large irrigated plantations in the desert which leads to strong updrafts and cloud formation! Well, thats what my model says anyway

New Scientist a while back had about geoengineering by planting trees and creating a rain shadow effect allowing more trees to grow, starting at an ocean with prevailing winds in right direction.

But I would assume most of this stuff would be very site specific, and it is a matter of tweaking something to allow feedback effects.


Another way is this guy, but again it needed seeding.