Seamless measurements of vertical air velocity associated with warm clouds through the integration of multiple retrieval techniques

Description

Vertical air motion retrievals in warm phase boundary-layer clouds are key to quantitatively describing cloud turbulence and for improving the retrieval of cloud and drizzle microphysical properties. This is especially true for the marine boundary-layer clouds observed by the ARM Mobile Facility during the Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) campaign on Graciosa Island and in light of the deployment of a new fixed ARM site there. Several methods have been proposed to retrieve the vertical air motion. We present current efforts to produce seamless measurements of vertical air velocity within and beneath drizzling and non-drizzling warm clouds, through the integration of these retrieval techniques. Recently developed radar Doppler spectra retrievals are effective in handling light, autoconversion-driven drizzle conditions. These are combined with retrievals from a radar-moments-based approach suited to heavier accretion-dominated drizzle. Comparisons near the operational drizzle intensity boundary of these two techniques provide opportunities for mutual validation. Doppler lidar is used to characterize sub-cloud velocities and to provide validation at the cloud base against in-cloud retrievals.