Drizzle in marine stratocumulus over the south eastern Pacific: measurement and role of mesoscale organization

Radar, lidar, and microwave radiometer measurements collected onboard the C130 during VOCALS-REx are used to estimate precipitation rates, adiabatic and actual liquid water paths and explore the relationship between mesoscale organization and drizzle. Precipitation rates at cloud base and ~100m above the ocean surface are estimated using reflectivity-rainrate relationships (based on in situ measurements of droplet spectra from VOCALS-REx) and radar-lidar retrievals for sub-cloud flight legs. Precipitation rates vary widely not only between flights and flight legs, but also within individual flight legs as a result of mesoscale circulations on scales of 10 km up to a few 10s of km. Here we examine how these circulations may lead to local enhancements in cloud thickness, and in turn local enhancements in precipitation rate.