This book presents the results of 20 years of atmospheric composition research studies carried out at the high-mountain (2,165 m a.s.l.) Observatory "O. Vittori" in Italy, part of the only global station in the Mediterranean region that belongs to the World Meteorological Organization's Global Atmosphere Watch (WMO/GAW). It provides a comprehensive study with updated results for the most important atmospheric climate-altering and pollutant compounds...