Analysis of the Vertical Profile of Aerosols over the Salton Sea during NASA SARP 2019

The Salton Sea is a large endorheic lake that is drying, thus exposing the lakebed that was once submerged. This lakebed, known as playa, emits both gases and particles into the atmosphere that have adverse effects on local air quality. Aircraft data from the 2019 Student Airborne Research Program (SARP) were used in order to determine the vertical distribution of aerosols over the Salton Sea to determine the overall effect of these emissions on the atmosphere. During a high-altitude pass at 3,200 meters over the Salton Sea, the Differential Absorption LIDAR (DIAL) instrument was used in order to analyze the remotely sensed aerosol optical properties. Following this, a lower altitude pass at 320 meters provided an opportunity to confirm DIAL data through comparison with the in-situ Langley Aerosol Research Group Experiment (LARGE) instruments as well as the NOAA In-Situ Measurements of Aerosol Optical Properties (NOAA-AOP) instrument. In order to differentiate between aerosol types, we referenced a published algorithm which creates eight classes of aerosol based on the lidar ratio at 532nm, backscatter color ratio, aerosol depolarization spectral ratio, and aerosol depolarization at 532nm. By further dividing the Salton Sea into three geographic regions, we analyzed the different aerosol types that make up the vertical layers in the lowest kilometer of the atmosphere, and identified which of the three distinct vertical layers were emitted from the Salton Sea and surrounding playa. In-situ data from the Aerosol Mass Spectrometer (AMS) instrument and Whole Air Sampling (WAS) Group instruments were also analyzed to evaluate the chemical characteristics of the lower layers. The lowest 500 meters of the atmosphere in the region was shown to be impacted by the Salton Sea, as aerosol at this elevation shared similar optical and chemical properties to maritime aerosol.