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Abstract
The measurement of quartz concentrations in a mineral dust layer with the Raman method was first presented by Tatarov et al. (Opt. Lett. 2005). In their study laser light was emitted at 532 nm and the quartz channel detected inelastically backscattered light at 546nm. This wavelength shift is due to Raman scattering at quartz grains.
In our study we use the multi-wavelength Raman lidar of the Gwangju Institute for Science and Technology, Republic of Korea (35.10N, 126.53E). This instrument allows us to infer vertical profiles of backscatter coefficients at 355, 532, and 1064nm, extinction profiles at 355 and 532nm as well as depolarization ratio profiles at 532nm. In Spring 2009 this lidar was equipped with two additional Raman channels at 360 and 546 for the measurement of quartz concentration in mineral dust layers immersed in East Asian anthropogenic pollution plumes.
First measurements with the new channels have been performed during the Asian dust season in March/April 2009. We detected Asian dust in the polluted boundary layer with plumes of dust in the free troposphere. The measurements in Gwangju will be continued until the end of the dust season in May 2009. After the dust season the 360-nm channel will be mounted to the multi-wavelength Raman lidar of the Leibniz Institute for Tropospheric Research, Leipzig, Germany. We often observe plumes of Saharan dust over Central Europe in early summer.