Anomalous Opaque Clouds Revealed by Collocated MODIS and CALIOP Retrievals

Abstract This paper examines discrepancies between cloud optical thickness (COT) retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) cloud product, and cloud opacity measurements from the Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar. The statistical analysis of a yearlong data set of collocated MODIS‐CALIOP retrievals reveals a striking discrepancy: many single‐layer liquid‐phase cloud pixels identified as transparent by CALIOP exhibit extremely high COT