Comparison of atmospheric aerosol properties inferred from direct and remote-sensing techniques

Continuous monitoring of atmospheric aerosol properties is very much essential in view of their wide variability in space and time. Both active as well as passive remote-sensing techniques are available apart from direct (in situ) methods to carry out such measurements. An attempt has been made in this paper to inter-compare aerosol features derived from the lidar (active sensor), multi-channel solar radiometer (passive sensor) and Andersen sampler (direct technique). The ground-level concentrations derived from the bistatic argon-ion lidar has been compared with those derived from the Andersen sampler. The results are found to be in fair agreement. The number-size distribution of aerosols retrieved from the multi-channel solar radiometer has been compared with the mass-size distribution derived from the Andersen sampler. The size spectra showed bi-modal distribution with accumulation mode around 0.08 μm and the coarse mode around 4.0 μm during the study period. Thus, the study reveals a good correspondence between the properties of aerosol particulates measured with different measurement techniques.