The Backscatter Cloud Probe with Polarization Detection (BCPD) measures cloud particle size distributions, which are then used to derive the total number concentrations, liquid water content (LWC), median volume diameter (MVD), and effective diameter (ED). The BCPD’s non-intrusive optical housing allows use in a range of ground-based or airborne applications with no contamination from ice crystal shattering or airflow distortions.