Vassilis Amiridis¹, Dimitris Balis², Elina Giannakaki²,Stylianos Kazadzis², Antti Arola³, Alexandros Papayannis⁴

¹Institute for Space Applications and Remote Sensing, National Observatory of Athens, 15236, Athens, Greece
²Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, 54124, Thessaloniki,Greece
³Finish Meteorological Institute, Helsinki, Finland
⁴National Technical University of Athens, Physics Department, Laser Remote Sensing Laboratory,Heroon Polytechniou 9, 15780 Zografou, Greece

 

The influence of biomass burning smoke on the aerosol loading in the free troposphere over Thessaloniki, Greece is discussed in this paper. Ten selected cases during 2001-2005 are presented, when very high aerosol optical depth values were observed, with the synergy of different remote sensing instruments. The data collected allowed the characterization of the optical properties of the biomass burning aerosols in this region, where limited information has so far been available. Four-day back trajectories indicated that air masses were advected from regions where strong forest fires occurred. In order to investigate the optical properties of biomass burning aerosols, we used a two- wavelength lidar system that combines Raman and elastic-backscatter observations in addition to Brewer spectrophotometer UV irradiance measurements and aerosol optical depth estimates. The retrieval of single scattering albedo employed the Brewer global irradiance measurements and radiative transfer model calculations. The Raman lidar measurements showed that for smoke aerosols the lidar ratios varied in the range of 45-90sr depending on the age of the smoke, while the estimated single scattering albedo was 0.960.02.