Mixed Layer Heights and Aerosol Products derived from the NASA LaRC airborne High Spectral Resolution Lidar during the First DISCOVER-AQ Field Mission

During July 2011, the first-generation NASA airborne High Spectral Resolution Lidar (HSRL-1) was deployed onboard the NASA Langley Research Center UC-12 aircraft during the first portion of the NASA DISCOVER-AQ mission (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) over the Baltimore-Washington D.C. metropolitan area. Profiles of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm) were derived from HSRL-1 measurements collected during 25 science flights in coordination with other participating research aircraft, satellites, and ground sites. The HSRL-1 measurements constitute a diverse dataset for use in characterizing the spatial and temporal distribution of aerosols, as well as the location and variability of the Mixed Layer (ML) height. The HSRL-1 data collected during DISCOVER-AQ are used to compute ML heights and determine the fraction of aerosol optical thickness (AOT) within and above the ML. Data measured from ozonesondes, Vaisala ceilometer, the UMBC Elastic Lidar Facility (ELF), Micro Pulse Lidar (MPL), and AERONET are compared to the ML height and AOT derived from HSRL-1. The ceilometer, ELF, and MPL provide aerosol backscatter measurements and derived ML height at several sites during the DISCOVER-AQ mission. Furthermore, ML heights were derived from the Goddard Earth Observing System – Version 5 (GEOS-5) model simulations of aerosol backscatter along the UC-12 flight tracks, and are assessed against the ML heights from the HSRL-1. Overall, we will show an in-depth comparison of lidar derived ML heights, which is important for air quality assessment and model simulations.