Thursday, 6 June 2002
Aircraft measurements of drop charges in Stratocumulus clouds: Observations and Model Comparisions
The average charges on cloud and aerosol particles were measured from the NCAR Electra using an aerosol electrometer during the 1997-1998 Lake-ICE project. Drops and ice particles were sampled with the NCAR Counterflow Virtual Impactor and interstitial aerosol particles were obtained using an aft-facing inlet. The mean particle charges were determined from the electrometer current, sample flow rates and particle concentrations. Interpretation of particle charges was aided using PMS cloud probe concentrations and spectra for drops and ice particles. Observations were also compared to calculated charges using simple a layer cloud model. In addition to describing the general features of our particle charge observations, we will suggest potential uses of charge measurements in studies of cloud microphysics.