Monitoring of the atmospheric boundary layer with lidar, sun-photometer and filter-sampling in Tokyo

Since the winter of 1995, we have routinely performed combined measurements with polarization lidar, sun-photometer, and filter-sampling. Such a so-called closer experiment is necessary and useful to cope with the variety of boundary-layer aerosols. The aims of the observation are as follows: i) study of the dynamics of the atmospheric boundary layer (ABL) by lidar, ii) use of depolarization ratio measurement for the study of the ABL and the characterization of aerosols, iii) to clarify the relationship between depolarization ratio and chemical component of the aerosol in the ABL, iv) comparison between the optical thicknesses derived from the lidar and the sun-photometer measurements, v) diurnal and seasonal changes of the above items, etc. We will present an overview of the study until now.