Atmospheric Measurement Techniques www.atmos-meas-tech.net 1867-1381 1867-8548 1 1 2008 10.5194/amt-1-1-2008 http://www.atmos-meas-tech.net/1/1/2008/ http://www.atmos-meas-tech.net/1/1/2008/amt-1-1-2008.html http://www.atmos-meas-tech.net/1/1/2008/amt-1-1-2008.pdf 1 8 2008-10-29 Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM) phase images G. Helas gth@mpch-mainz.mpg.de M. O. Andreae Max Planck Institute for Chemistry, Biogeochemistry Department, P.O.Box 3060, 5020 Mainz, Germany We show that atomic force microscopy (AFM) phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. 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