Atmospheric implications for mixed stochastic-singular models of ice nucleation
 
Authors
Raymond A Shaw — Michigan Technological University
Dennis Niedermeier — Leibniz Institute for Tropospheric Research
Susan Hartmann — Leibniz Institute for Tropospheric Research
Frank Stratmann — Leibniz Institute for Tropospheric Research
Heike Wex — Leibniz Institute for Tropospheric Research
Category
Aerosol Properties
Description
Evidence exists that heterogeneous ice nucleation can be described by mixed stochastic-singular models. Recently, for example, our group introduced a “soccer-ball model” that envisions particles made up of surface sites or patches with different nucleation barriers. The key assumption is that classical nucleation theory applies on each patch. The number of patches on a particle and the distribution of nucleation barriers (parameterized through the contact angle) can be varied independently, and therefore the model can describe the transition from purely stochastic behavior to nearly idealized singular behavior. We review some recently published measurements in the context of the soccer-ball model and consider the degree to which model parameters can be fitted unambiguously. This, in turn, allows us to consider some general implications of extending laboratory measurements to the atmosphere, especially when those measurements are interpreted in the stochastic or singular limits.