In “Solar Wind Mechanism Suggested for Weather and Climate Change” [Eos, August 9,1994], Brian A. Tinsley suggests that solar activity is modulating weather and climate through the effects it produces on the Earth's fair-weather electric field. This may well be true. It is questionable, however, whether the fair-weather electric field is strong enough to cause ice crystal formation in clouds by electrofreezing, as he has assumed.
From Pruppacher , it is evident that demonstrations of electrofreezing involve electric fields about a thousand times more intense and a million-fold more energetic than the electric field Tinsley believes is causing the formation of ice crystals in clouds. Acceptance of the idea that the fair weather field plays a significant role in the glaciation of clouds must await demonstrations that electrofreezing can be produced by electric fields of less than 100 Vm−1.