Changes of Aerosol Properties by Nearby Clouds

Aerosol measurements in partly cloudy regions play a crucial role in understanding aerosol-cloud interactions and assessing aerosol radiative effects.  A majority of all clear-sky pixels lie within a zone where aerosol properties vary in response to nearby clouds and cloud-related processes, but the exact causes and radiative effects of these variations have remained elusive.  Interpreting passive satellite aerosol observations is especially challenging near clouds because of issues such as cloud contamination and cloud adjacency effects.  In this presentation, we discuss a synergy of passive and active observations to distinguish the sources of particle changes ranging from aerosol humidification to retrieval artifacts.