Seeding cloud - UK history

[Tartan Giant]

Please excuse the far-fetched question!

After the floods in Cornwall (Boscatle) there have been mutterings that in 1953, cloud seeding trials over Salisbury Plain were carried out, which some say caused severe floods!

I think that is absolute crap, but the Press do throw up some tripe.

Has anyone here any recollections of such goings on over the Salisbury Plains, and any rain resulting from such "trials" - and indeed causing flooding (sorry, but I am biting my tongue here!).

Cheers

TG

[Pontius Navigator]

TG, weather control trials were all the rage in the 50s. I think sowing the cloud with silver nitrate.

Yes, it was probably done over SP.. I think the US even used rockets to try and spark rain.

I am not sure of the exact purpose, whether it was to provide a solution to dought or to control where the rain would drop. Get it right and your side stays dry.

[samusi01]

For more info on military cloud seeding, I'd recommend that you try Googling Operation Popeye - was a Vietnam op to try raining out the Ho Chi Minh trail.

[Tartan Giant]

Thanks chaps for the reply.

I knew about the Vietnam op - interesting way to fight a war.

What I'm after realy is definitive proof sufficient rain can be produced from our August Cu or StrataCu to cause a major flood -as proposed by some (BBC).

Raise an eyebrow here:
http://news.bbc.co.uk/1/hi/uk/1516880.stm


I shall continue to dig for more seed!

Cheers

TG

[Archimedes]

The alternative point of view is given at http://www.weatheronline.co.uk/feature/ne180901.htm


with a later piece at:

http://www.weatheronline.co.uk/feature/pe200802.htm

Eden is the weather man for the Daily Telegraph and, unless there's another Philip Eden about, he also does the weather for Radio Five.

The New Scientist also did a short piece on it:
http://www.newscientist.com/news/news.jsp?id=ns99991219

While this takes me back to geography lessons at school!

http://www.exmoor-nationalpark.gov.uk/About_Exmoor/ExmoorLyntonFloods1952.htmhttp://www.weatheronline.co.uk/feature/pe200802.htm

[Tartan Giant]

Thanks a million Archimedes:ok:

Just what I wanted and could not find........ makes you want to shout "eureka":D

Thanks chaps.

TG

[Archimedes]

Glad to help :ok:

[Milt]

Cloud seeding is done by burning silver iodide which produces copious condensation nuclei.

Having done some of this myself I conclude that it is successful most of the time on Cumulus clouds which are going to rain anyway. You can just make them put it where you want it by seeding a cloud upwind by about 30 minutes.

Seeding is going on now in the Oz alps with burners on the peaks. Already much enhanced snow falls this winter. Results to be analysed by determination of the extent of silver iodide crystals in the snow.

[Tartan Giant]

G'Day Milt,

Thanks for that first hand account of the process - very interesting way of getting more snow for the tourists!

Maybe they should try that now and then in Aviemore, Scotland?

Just a little question; what weight of silver iodide/sortie did you carry to achieve the aim?

Cheers

TG

[Scud-U-Like]

Can't help you with your specific request, TG, but I seem to recall the Russians were/are big on cloud seeding:

http://truthnews.com/world/2003060012.htm

http://www.abcnews.go.com/sections/scitech/DailyNews/weathermakers020924.html

http://www.weathernotebook.org/transcripts/1998/04/30.html

Fascinating subject: hardly surprising the press love it.

[Tartan Giant]

Thanks again, Scud-U-Like. Very good links with additional info.

Cheers

TG

[samusi01]

Check out www.weathermod.com too. US company that works around the world. Has some background info on precip increase as well as hail supression. There was a thread on this in the test pilots forum a while back.

[Tartan Giant]

Thanks again - this time to samusi01

Interesting stuff going on egh!

Cheers

TG

[Fox3snapshot]

There is a company conducting cloud seeding here in the Middle East and by all accounts are achieving good results. Summer is the time for the large CB buildups in the Interior and Jebal's (mountain regions) and the with a little extra encouragement from the seeders the Wadi's (creeks) are flowing!

:ok:

[Milt]

TG

Burners for aircraft can be quite small - usually about 1m x 15cm.

Usual concentration of AgI is 2% in acetone.

Aircraft being used by the Tasmanian Hydro is a Cessna Conquest.

Would be interesting to see the pilot's log book with a lot of IFR time around freezing level. Guess he would know a lot about airframe icing.

If you are a PPRuNer some comments please.

[Occasional Aviator]

I seem to recall that some east european countries use rockets to set off CBs to prevent hail (and thus stop crops being ruined). Anyone have any further on this?

[Greenleader]

As a humourous aside, why would anyone want to seed clouds in the UK - it's not called mud island by southern hemishere residents without good reason - place gets too much rain and is too damn wet without any help!

[samusi01]

Most of the mid-level seeding is done in the -10C range (this depends on the seeding agent). The clouds are supercooled liquid water, so you zip in one side and come out the other with a load of ice - the more ice the better. Higher SCLW content means that the seeding agent will be more effective.