We had contact with a company involved in cloud seeding to avoid hail-storms. An airplane equipped with a burner emitting silver-iodide nuclei was flying under cloud base. By updrafts the silver iodide is injected into higher elevations where ice particls form on the nuclei. The growing ice crystals then fall through the cloud layers with supercooled droplets. Those droplets then attach to the ice crytals by impaction freezing forming snow flakes and graupel which melts when falling through the zero centigrade regions into warmer air forming rain. Thus the AgI seeding may be called cloud seeding, but it does not act as CCN, rather as IN. Thus in my opinion the article on atmospheric alchemy seems misleading as it invokes a direct influence on the droplets which would require quite large amounts of nucleator chemicals.
Biological Ice Nucleators