This Postdoctoral Research Fellowship (PRF) supports studies to investigate the factors that influence the uptake of water by small particles in the atmosphere. Factors that may be important include temperature, relative humidity, and particle phase morphologies, such as whether a particle may be a mixture of solids, semi-solids, and/or liquids, or may have various surface coatings. These factors influence particle growth and the formation of clouds in the atmosphere. Hence this research is important for understanding how atmospheric aerosols influence climate.
The scientific questions that this research addresses include the following: (1) What role does particle phase morphology play in the activation and growth of cloud condensation nuclei; (2) Is there evidence of complex particle phase behavior in the natural atmosphere; and (3) How well do current state-of- the-art thermodynamic and kinetic models capture the complex relationship between particle phase and water vapor uptake? Laboratory and field measurements will be coupled with data from thermodynamic and kinetic models to accomplish the objectives of the research. Most of this research will take place in the Linde and Robinson Laboratory chamber facility at the California Institute of Technology.