Tomoaki Nishizawa

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We developed an algorithm to estimate the vertical profiles of extinction coefficients at 532 nm for three aerosol types that are water-soluble, soot, and dust particles, using the extinction and backscattering coefficients at 532 nm for total aerosols derived from high-spectral-resolution lidar (HSRL) measurements and the receiving signal at 1064 nm and(More)
Retrieving distributions of aerosol components from lidar measurements is useful for studying aerosol phenomena and the effects of aerosols on climate change and global and regional environment. It is especially useful for validating chemical transport models. In this paper, we describe aerosol component retrieval methods for ground-based lidars, and(More)
A lidar for measuring fluorescence from atmospheric aerosols was constructed with a third harmonic Nd:YAG laser, a 1-m diameter telescope, and a 32-channel time-resolved photon-counting spectrometer system. Fluorescence spectrum and vertical distribution of fluorescent aerosols in the lower atmosphere were observed during the nighttime with excitation at(More)
Natural mineral dust and heavy anthropogenic pollution and its complex interactions cause significant environmental problems in East Asia. Due to restrictions of observing technique, real-time morphological change in Asian dust particles owing to coating process of anthropogenic pollutants is still statistically unclear. Here, we first used a newly(More)
We perform network observations of Asian dust and air pollution aerosols in the east Asian region using automated twowavelength (1064nm, 532nm) polarization (532nm) lidars [1-3]. At present, we operate the lidars continuously at 15 locations including cooperative observation sites. The data from the network are used in various studies including(More)
To better understand and quantify aerosol radiative forcing and reduce the uncertainty of its climate effect, it is of vital importance to realize the aerosol components classification and quantification. For this purpose, we developed a powerful lidar system employed a multi-channels spectrometer, with capabilities of providing high spatial and temporal(More)
This paper presents some research results pertaining to the application of solidified coal ash (SCA) for improving the stability of soft ground. The results pertain to the physical properties of SCA required for use as an alternative to sand in sand compaction piles (SCPs), and the assessment of possible environmental impacts resulting from construction of(More)
We developed a multiple-field-of-view multiple-scattering polarization lidar (MFMSPL) to study the microphysics of optically thick clouds. Designed to measure enhanced backscattering and depolarization ratio comparable to space-borne lidar, the system consists of four sets of parallel and perpendicular channels mounted with different zenith angles.(More)
REFERENCES AND LINKS [1] N. Sugimoto, I. Matsui, A. Shimizu, T. Nishizawa, Y. Hara, C. Xie, I. Uno, K. Yumimoto, Z. Wang, S-C. Yoon, “Lidar network observations of troposheric aerosols”, Proc. SPIE Vol. 7153, Lidar Remote Sensing for Environmental Monitoring IX, 71530A (2008). [2] NIES lidar web site, http://www-lidar.nies.go.jp/ [3] J. Boesenberg, R. Hoff,(More)