This proposal will develop a mobile, scanning, eye-safe lidar (light detection and ranging) to fully apply the laser backscatter depolarization technique to the remote characterization of aerosols suspended in the atmosphere. Although even simple lidars can be effective at detecting atmospheric aerosols and mapping their vertical and spatial distributions, eye-safety concerns severely limit their application in the field. It is well established that linear depolarization measurements offer unique capabilities to detect and classify the nature of clouds and aerosols, and a variety of such data will be obtained using an improved two-channel mobile lidar system. Such lidars unambiguously separate spherical from nonspherical particles, and further are sensitive to the exact shape of irregular particles. The lidar system will be evaluated in the field by sampling known aerosol types in Alaska such as transported Asian desert dust, Arctic haze, ice fog, tree pollens, forest fire smoke,internal combustion engine by-products, and sea spray. In addition, the system design will accommodate circular and complete Stokes parameterization of the backscattering for future applications to fully evaluate the eye-safe polarization diversity lidar research field.
This project will create a mobile lidar research facility that will grow into an advanced test-bed for studying the application of lidar polarization techniques to aerosol and cloud research. The project will help train a graduate student in the lidar field and contribute to the training of meteorological experimentalists. Important future scanning research applications are possible in the observation of forest fires, urban pollution sources, and the spatial variability of clouds and precipitation. Polarization lidar techniques have unique potential for identifying the nature of particles suspended in the atmosphere. Many of the aerosol targets have analogs in the detection of hazardous materials.
