The ice phase in clouds is key for the hydrological cycle and climate. Globally the majority of precipitation reaching Earth´s surface involves the cloud ice, because ice crystals can often grow rapidly to large sizes to initiate gravitational settling and precipitation. In addition, pure ice clouds play a key role in the Earth´s climate and energy budget by contributing to a net positive radiative forcing. These clouds form when ice forms on aerosols that cat as ice nucleating particles (INPs). However, only about 1 out of 106 aerosols can act as INP.
Our research focuses on understanding the chemical and physical aerosol particle properties that allow them to act as INPs and form ice crystals. We also quantify the atmospheric temperature and relative humidity conditions at which ice nucleation can take place on different types of aerosols, and explore the different modes or mechanisms through which ice nucleation can proceed. We study ice nucleation in the laboratory using advanced instrumentation including continuous flow diffusion chambers.
The results from these studies provide a fundamental understanding for accurately representing ice nucleation and cloud microphysical processes in climate models.
