An Aerosol Extinction Coefficient Retrieval Method and Characteristics Analysis of Landscape Images.

Images based on RGB pixel values were used to measure the extinction coefficient of aerosols suspended in an atmospheric state. The pixel values of the object-image depend on the target-object reflection ratio, reflection direction, object type, distances, illumination intensity, atmospheric particle extinction coefficient, and scattering angle between the sun and the optical axes of the camera, among others. Therefore, the imaged intensity cannot directly provide information on the aerosol concentration or aerosol extinction coefficient.

Investigation of East Asian clouds with polarization light detection and ranging.

In this paper we present results of investigation of the main optical properties of East Asian clouds with a ground-based polarization lidar placed in Daejeon, Republic of Korea. Asian dust is located in elevated layers of the atmosphere in spring, travels long distances, and causes significant damage to ecology. We present backscattering matrices of clouds obtained from polarimetric remote measurements which comprise information on the scattering and absorption properties of cloud particles, their morphology, and spatial orientation.

Measuring cloud droplet effective radius and liquid water content using changes in degree of linear polarization along cloud depth.

Two important parameters of liquid clouds are the cloud effective size (CES) and liquid water content (LWC). To measure these parameters, we have used two multiple scattering depolarization effects: (1) the slope of the degree of linear polarization (SLDLP) at the cloud base, and (2) the saturated degree of linear polarization (SADLP) at infinite altitude. We used Monte Carlo simulation to validate this method, with the assumption that the water cloud droplet size follows a Gamma distribution.

Raman and fluorescent scattering matrix of spherical microparticles.

In this paper, we have investigated the main properties of the Raman and fluorescent matrix of scattering by microspheres using the matrix scattering formalism. The coherent and incoherent inelastic scattering of incident light by a microsphere is described by the Stokes parameters. We demonstrate the main symmetry properties of the coherent and incoherent Raman and fluorescent scattering matrices.

A newly designed single etalon double edge Doppler wind lidar receiving optical system.

A new optical Doppler lidar receiving system which can measure Doppler-shifted incoherent scattering light has been proposed and tested. This system functions in a manner similar to two edge filters and consists of a single etalon, a polarization beam splitter, and mirrors that can guide scattered light into a single etalon with two different angles. These two incident angles are precisely adjusted by the polarization beam splitter and mirrors.

Suggestion for qualitative lidar identification of different types of aerosol using the two-wavelength rotational Raman and elastic lidar.

Aerosols are important parameters in the meteorological and environmental fields, and remote aerosol identification is extremely desirable. We have proposed and designed a two-wavelength (355 and 532 nm) rotational Raman and elastic lidar that can measure the wavelength dependence of the aerosol backscattering coefficient without any assumptions about the Angström coefficient or the overlapping function from low (100 m) to high (10 km) altitude, depending on the weather conditions. We have measured the differences in the backscattering ratios (BRs) among a cloud, aerosol in the boundary layer, and Asian dust.

Rotational Raman lidar for obtaining aerosol scattering coefficients.

Two-channel lidar signals that are composed of total rotational scattering and elastic signals provide good information about aerosol scattering coefficients. We can calculate the aerosol backscattering coefficient and extinction coefficient directly, without making any assumption or calibration. Generally, a high-spectral-resolution lidar is used for aerosol monitoring, but we have designed a new low-spectral-resolution lidar system that contains both kinds of scattering information simultaneously, and we have retrieved the aerosol scattering coefficient.