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Atmospheric particulate matters (PM) are tiny pieces of solid or liquid matter associated with the Earth’s atmosphere. They are suspended in the atmosphere as atmospheric aerosol. Recently, density of fine particles PM2.5, diameter of 2.5 micrometers or less, from China is serious environmental issue in East part of Asia. In this study, the authors have developed a PM2.5 density distribution visualization system using ground-level sensor network dataset and Mie lidar dataset. The former dataset is used for visualization of horizontal PM2.5 density distribution and movement analysis, the latter dataset is used for visualization of vertical PM2.5 density distribution and movement analysis.

Greenhouse gases Observation SATellite (GOSAT) was launched to enable the precise monitoring of the density of carbon dioxide by combining global observation data sent from space with data obtained on land, and with simulation models. In addition, observation of methane, another greenhouse gas, has been considered. For validation of GOSAT data products, ground-base observation with Fourier Transform Spectrometer (FTS), aerosol lidar and ozone-DIAL (DIfferencial Absorption Lidar) at Saga University, JAPAN has been continued since March, 2011. In this article, observation results obtained from aerosol lidar are reported.

An web-base data acquisition and management system for GOSAT (Greenhouse gases Observation SATellite) validation lidar data analysis is developed. The system consists of data acquisition sub-system (DAS) and data management sub-system (DMS). DAS written in Perl language acquires AMeDAS ground-level meteorological data, Rawinsonde upper-air meteorological data, ground-level oxidant data, skyradiometer data, skyview camera images, meteorological satellite IR image data and GOSAT validation lidar data. DMS written in PHP language demonstrates satellite-pass date and all acquired data.

Lidar observations of stratospheric aerosols have been performed at Ny-Aalesund (79 degrees N, 12 degrees East), Svalbard every winter since January 1994. We detected many PSC events in the stratosphere under low temperature condition, especially in 1994/95, 1995/96, 1996/97 winter campaigns. Meanwhile in the Antarctic, lidar observations were made from April, 1997 to January, 1998 at Dome Fuji (78 degrees South, 40 degrees East), and many PSCs were detected almost every day from the end of May to mid October. In the Arctic, PSC layers at the initial stage of appearance were composed mainly of solid particles in each winter season and the layers at sufficiently low temperatures were composed of spherical particles. In the Antarctic, PSCs similar to those over Ny- Aalesund were also detected frequently while the polar vortex was developing or the vortex was unstable. But after a remarkable decrease in the temperature by the invasion of blocking high into the polar vortex, PSCs detected were mainly composed of solid particles.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A comparative measurement of the free tropospheric aerosol particles using a ground-based Raman lidar and in-situ sampling instruments on board an aircraft was made over central part of Japan (35-36°N, 136-137°E) in the Asian dust period on April 23, 1996. We compared the aerosol properties measured with the lidar (aerosol backscattering coefficients and the depolarization ratio at the wavelength of 532 nm) and those obtained with the aircraft-based instruments (aerosol shape and surface feature, number size distribution, and chemical composition). The aerosol backscattering coefficients calculated from the aerosol size distribution obtained with the airborne optical particle counters (OPCs) showed good agreements (mean relative difference of 22%) with those measured with the lidar above the altitude of 3.1 km, but showed large difference (mean relative difference of 50%) below 3.1 km. The aerosol depolarization ratios correlated well with the fractions of the backscattering coefficient of the coarse mode particles (radius>0.5 μm) in the total aerosol backscattering coefficient calculated from the OPCs data above 3.4 km. This suggests that the coarse mode particles that consisted mainly of nonspherical mineral dust particles predominantly contributed the depolarized signals in this altitude region. The aerosol depolarization ratio of the coarse mode particles was estimated to be 164% at 5.3 km.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.