This special issue of the Journal of Geophysical Research arose out of a conference entitled ‘The Non Urban Troposphere Composition,’ held on November 10-12, 1976, in Hollywood, Florida. The symposium was a joint effort of the American Geophysical Union and the American Meteorological Society and was cosponsored by the U.S. Department of Transportation, the U.S. Environmental Protection Agency, the U.S. Energy Research and Development Administration, the National Aeronautics and Space Administration, the National Center for Atmospheric Research, and the National Oceanic and Atmospheric Administration (NOAA). M. H. Bortner (General Electric Company) and Wilmot Hess (NOAA) convened the conference and were assisted by P. J. Crutzen.
Each paper in this issue was presented in whole or in part at the Non Urban Troposphere Composition Symposium and was subsequently submitted to JGR's review process. Not all of the papers presented at thé symposium were submitted for publication, and not all of those submitted were accepted. Also, one of the symposium papers had already been accepted at the time of presentation and was published in JGR several months ago. It is hoped that the collection of papers in this issue will be useful to readers of JGR and will comprise a lasting contribution to the literature of the field. The reviewing, editing, and publication of these papers within 13 months of their presentation would not have been possible without, first, the insistence of Dr. Bortner and Dr. Hess that symposium speakers prepare written manuscripts before the meeting and, second, the guidance and energy of the Editor, G. T. Csanady, and his assistant, May Reese.