Warm turbulent cloud

Toy model

Gregory FalkovichM. Stepanov, A. Fouxon, M. Vucelja, A. Pumir ,

A. Seminara, A. Celani, A. Mazzino ,

S. Derevyanko, S. Turitsyn

March 24, 2009

Strepsiades: Do you think Zeus always rains new water down or does the sun draw the old up to be re-used?Amynias: I don’t know and I don’t care.Strepsiades: How do you expect to get your money if you know nothing of meteorology?

Aristophanes, CLOUDS

preferential concentration

sling effect

100 sec

or

Timescales

Distributions of droplets over sizes

With the account of supersaturation fluctuations

• Toy model of cloud evolution that incorporates both macroscopic and microscopic effects of turbulence

• Hygroscopic cloud seeding may be a practical possibility

• Much further work is needed on • collisions• spectrum broadening during condensation• latent heat release and convection• Account of vertical structure and ice• …..