Molecules on Ice

Every spring over the Antarctic, an ozone hole forms—a localized region where the ozone concentration in the atmosphere is greatly reduced. The ozone is destroyed by a complex chain of chemical reactions beginning with hydrochloric acid. In his Perspective, Clary describes work published in the same issue by Gertner and Hynes ( p. 1563 ) that identifies a new mechanism by which the HCl sticks to ice particles.