Will H. Cantrell

Biography

Why does water in Earth's atmosphere condense into cloud droplets when and where it does, and why does that water sometimes freeze? Those questions are the broad motivation for my research here over the past 10 years. Water in the atmosphere will not start freezing unless it's really cold (about -36 C) or unless it is catalyzed by some foreign substance like mineral dust or certain bacteria. One of the most puzzling aspects of the latter case is that it seems if the mineral dust is at the surface, the water freezes more readily than if the dust is immersed within the water. My students and I are trying to understand this phenomenon, called contact freezing, by conducting controlled, laboratory experiments in an attempt to isolate the most important physical and chemical characteristics of the particles that catalyze the phase transition. I am also a member of the Michigan Tech team designing a chamber that will be able to simulate cloud conditions in a turbulent environment, a one-of-a-kind facility that will enable us to investigate some of the most stubborn and vexing problems in cloud physics and chemistry.