Campaign : Colorado: Ice Nuclei and Cloud Condensation Nuclei Characterization
2010.11.15 - 2011.04.25
Lead Scientist : Daniel Cziczo
Description
The relationship between aerosol particles and the formation of clouds is among the most uncertain aspects in our current understanding of climate change. Warm clouds have been the most extensively studied, in large part because they are normally close to the Earths surface and only contain large concentrations of liquid droplets. Ice and mixed-phase clouds have been less studied even though they have extensive global coverage and dominate precipitation formation. Because they require low temperatures to form, both cloud types are infrequently found at ground level resulting in more difficult field studies. Complex mixtures of liquid and ice elements, normally at much lower concentrations than found in warm clouds, require precise separation techniques and accurate identification of phase. Because they have proved so difficult to study, the climatic impact of ice-containing clouds remains unresolved.
In this study we performed (1) inertial and phase separation of ice crystals and liquid droplets from unactivated aerosol and (2) initiate nucleation of ice crystals and liquid droplets using cloud chambers. We analyzed the aerosol particles within crystals and droplets to determine the size and composition of the precursors to cloud formation. In collaboration with the StormVEx scientists our goal was to relate these findings to the cloud characteristics and the effect of anthropogenic activities.










