Dust aerosol or sand storm has become the popular attention topic of the world currently. In order to understand and
study the aerosol optical properties, particularly for dust aerosol produced in the spring weather condition, and to
investigate their effects on atmospheric pollution status, a Mie scattering lidar was developed to detect the time and
spatial distribution of the aerosol and the atmospheric visibility at Xi'an, China. The lidar system employs a Nd:YAG
pulsed laser at a eye-safe wavelength of 355nm as a transmitter, and a Schmidt-Cassegrain telescope as a receiver. A
spectroscope filter combined with a high-resolution grating was used to separate the main lidar returns and to block the
solar background simultaneously for daytime measurement. The observation experiments with lidar have been carried
out from the spring of 2007. The data of the extinction coefficients of aerosol and atmospheric visibility taken under the
different atmospheric conditions are demonstrated. The comparison results of visibility measurement using lidar and
other tool show that the lidar system is feasible, and the aerosol observation results show that the main aerosol pollution
of Xi'an is from the floating dust aerosol, which is usually suspended at a height of near 1km.
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