We present the demonstration of a high spectral resolution lidar (HSRL) capable of directly retrieving vertical profiling of the aerosol-to-molecular backscatter ratio up to 8 km during daytime operation and 14 km at night. Unlike conventional elastic lidars, the HSRL provides calibrated aerosol optical property profiles without assuming a lidar ratio or requiring auxiliary instruments such as solar radiometers or radiative transfer models, which are commonly needed by micro pulse lidars or ceilometers. This capability is particularly critical for wildfire studies, where smoke plumes exhibit rapidly changing aerosol properties that make such assumptions unreliable. Wildfires generate complex smoke plumes with significant impacts on air quality, visibility, and climate forcing. Vertically resolved aerosol measurements from the HSRL can be used to verify and refine smoke and radiation transport models. The HSRL was developed under the NSF EPSCoR SMART FIRES project as part of the Smart Optical Sensors initiative to advance the study of smoke-borne aerosols. The lidar transmits eye-safe 780 nm light and utilizes a rubidium-87 atomic filter in the molecular channel to isolate the molecular backscatter from the total lidar return. This spectral separation enables direct comparison of molecular and total returns to calculate the aerosol-to-molecular backscatter ratio, a key indicator of aerosol loading in the lower atmosphere. The system is housed in an environmentally controlled enclosure for future field deployments near active wildfires. This poster presents the HSRL architecture and initial aerosol-to-molecular backscatter measurements collected in Bozeman, Montana, demonstrating the instrument’s performance in a region frequently impacted by wildfire smoke originating in the western United States and Canada.
Demonstration of a high spectral resolution lidar for vertical profiling of aerosols