Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 6 4 2009 10.5194/bg-6-721-2009 http://www.biogeosciences.net/6/721/2009/ http://www.biogeosciences.net/6/721/2009/bg-6-721-2009.html http://www.biogeosciences.net/6/721/2009/bg-6-721-2009.pdf 721 737 2009-04-30 Microbiology and atmospheric processes: biological, physical and chemical characterization of aerosol particles D. G. Georgakopoulos V. Després J. Fröhlich-Nowoisky R. Psenner P. A. Ariya M. Pósfai H. E. Ahern B. F. Moffett T. C. J. Hill Agricultural University of Athens, Athens, Greece Max Planck Institute for Chemistry, Mainz, Germany Johannes Gutenberg University, Mainz, Germany University of Innsbruck, Innsbruck, Austria McGill University, W. Montreal, Canada University of Pannonia, Veszprem, Hungary University of East London, London, UK The interest in bioaerosols has traditionally been linked to health hazards for humans, animals and plants. However, several components of bioaerosols exhibit physical properties of great significance for cloud processes, such as ice nucleation and cloud condensation. To gain a better understanding of their influence on climate, it is therefore important to determine the composition, concentration, seasonal fluctuation, regional diversity and evolution of bioaerosols. In this paper, we will review briefly the existing techniques for detection, quantification, physical and chemical analysis of biological particles, attempting to bridge physical, chemical and biological methods for analysis of biological particles and integrate them with aerosol sampling techniques. We will also explore some emerging spectroscopy techniques for bulk and single-particle analysis that have potential for in-situ physical and chemical analysis. 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