Actinic Radiation and Photolysis Processes in the Lower Troposphere: Effect of Clouds and Aerosols - W. Junkermann; C. Brühl; D. Perner; E. Eckstein; T. Trautmann; B. Früh; R. Dlugi; T. Gori; A. Ruggaber; J. Reuder; M. Zelger; A. Hofzumahaus; et al. (Journal of Atmospheric Chemistry, 2002)