A dual rotating retarder Mueller matrix polarimeter is described that operates in the UV-VIS-NIR region. The
components were selected to allow the instrument to seamlessly span the 300-1100 nm region with a
resolution of 2 nm or higher. Complete Mueller matrix polarimetric characterizations of a host of optical
components have been performed and a select few will be presented. This instrumentation is expected to
enable exploratory research into novel methods for point and standoff detection of chemical and biological
threats in the atmosphere. To this end, surrogates of hazardous materials as well as background aerosols must
be characterized and differentiating features in the polarization properties correlated to specific morphologies.
Investigations specific to this application is underway.
Local and regional pollution interact at the interface between the Planetary Boundary Layer and the Free Troposphere. The vertical distributions of ozone, aerosols, and winds must be measured with high temporal and vertical resolution to characterize this interchange and ultimately to accurately forecast ozone and aerosol pollution. To address this critical issue, the Regional Atmospheric Profiling Center for Discovery (RAPCD) was built and instrumented in the National Space Science and Technology Center on the UAH campus. The UV DIAL ozone lidar, Nd:YAG aerosol lidar, and 2-micron Doppler wind lidar, along with balloon-borne ECC ozonesondes, form the core of the RAPCD instrumentation for studying this problem. Instrumentation in the associated Mobile Integrated Profiling (MIPS) laboratory includes a 915Mhz profiler, sodar, and ceilometer. The collocated Applied Micro-particle Optics and Radiometry (AμOR) laboratory hosts the FTIR, MOUDI, and optical particle counter. Using MODELS-3 analysis by colleagues, and cooperative ventures with the co-located National Weather Service Forecasting Office in Huntsville, AL, we are developing a unique facility for advancing the state-of-the-science in pollution forecasting.
Algorithms to simulate the statistical microphysical and optical models for aerosol and polar stratospheric cloud (PSC) are described. Examples of such models for stratospheric and tropospheric aerosols and PSC are given. Different ways of applying the statistical aerosol and cloud models are discussed: - optimal parameterization of spectral dependences of aerosol extinction coefficient using the natural orthogonal basis; - multiple regression for estimating the optical parameter from measured one (for example, estimation of scattering coefficients from SAGE III multiwavelength measurements of aerosol extinction coefficients); - retrieval of microphysical properties of stratospheric aerosol and PSC from SAGE III extinction measurements; - lidar sounding.
An algorithm for the combined retrieval of ozone, NO2, spectral aerosol extinction profiles and different microphysical properties of stratospheric aerosol is described. Principal features of the algorithm are the use of simulated statistical aerosol models as a priori information and optimal parameterization of spectral dependence of aerosol extinction coefficients (by expanding in natural orthogonal basis). The statistical microphysical models of stratospheric aerosols are used for retrieving the aerosol size distribution function. Results of numerical experiments for the study of error budget of this algorithm are given. Data of slant path transmittance spectral measurements by SAGE III (Meteor-3M) have been processed and analyzed. Results of retrieving the different atmospheric parameters are compared with independent measurements.