Lidar and Polarimeter Measurements of Water Clouds during the North Atlantic Marine Aerosols and Ecosystems Study (NAAMES) Campaigns

The NASA Langley High Spectral Resolution lidar (HSRL) and the NASA GISS Research Scanning Polarimeter (RSP) were deployed onboard the NASA C-130 during three field campaigns as part of the NASA's Earth Venture-Suborbital (EVS) North Atlantic Aerosol and Marine Ecosystems Study (NAAMES) during November 2015, May 2016, and September 2017. The main objectives are to study the phases of the North Atlantic annual plankton cycle and to investigate remote marine aerosols and their impact on boundary layer clouds. This presentation extends the analysis of the HSRL profile retrievals of the cloud top that includes cloud extinction and lidar ratio (extinction/backscatter ratio). The lidar ratio retrievals are compared to the Research Scanning Polarimeter to assess consistency and differences between the two remote sensors. The combination of the measurements from RSP and HSRL enables retrievals of cloud droplet number densities at cloud top. The remote measurements are further compared to those made by the Cloud Droplet Probe (CDP) that is part of the NASA Langley Aerosol Research Group Experiment (LARGE) instrument suite. With three campaigns, histograms of the CNDC measurements from remote sensors are presented to highlight differences between the different seasons.