Mixed Layer Heights derived from the NASA Langley Research Center airborne High Spectral Resolution Lidar

The first-generation NASA airborne High Spectral Resolution Lidar (HSRL-1), onboard the NASA Langley Research Center's B200 aircraft, has been deployed for nineteen field missions in North America from 2006 to 2012 to aid in characterizing aerosol properties. Measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm) during 349 science flights, many in coordination with other participating research aircraft, satellites, and ground sites, constitute a diverse data set for use in characterizing the spatial and temporal distribution of aerosols, as well as location and variability of the Mixing Layer (ML) height. As will be shown, the HSRL-1 data collected during these missions are used for computing ML heights and for determining the fraction of aerosol optical thickness within and above the ML, both of which are important for air quality assessments. Additionally, we describe the spatial and temporal variations in ML heights found in the diverse locations associated with these experiments. Lastly, we explain how the ML heights derived from HSRL-1 have been used to assess Planetary Boundary Layer (PBL) simulations produced using various models, including Weather Research and Forecasting - Chemistry (WRF-Chem), NASA Goddard Earth Observing System - version 5 (GEOS-5), and European Centre for Medium-Range Weather Forecasts - Monitoring Atmospheric Composition and Climate (ECMWF-MACC).