Cloud Seeding - Weather Modification

• Often, cold clouds do not precipitate for two reasons:

  1. cloud does not have enough ice nuclei (remember, ice particles will likely grow more readily than water particles)

  2. not enough vapor in the cloud (e is to low)

• Hence, the idea of cloud seeding:

  • consider the cloud to the right -->>

    • e_s (water) = 5 mb
    • e_s (ice) = 2 mb
    • e (cloud) = 3 mb

  • ice could grow, but don't have enough ice nuclei....., what to do????

  • add more ice nuclei to a cloud - form more ice particles in the cloud that may grow to precip size