Methanol measurements in the lower troposphere near Innsbruck (047°16′N; 011°24′E), Austria

Diurnal variations on a time scale of minutes of the mixing ratios of methanol were measured using proton transfer reaction mass spectrometry (PTR-MS) technique during 67 days throughout the time span from November 1996 to July 1998 together with benzene and other volatile organic compounds at the western outskirts of Innsbruck, Austria. Comparison with the course of the mixing ratio of benzene, which served as marker for traffic emissions, as well as the observation of a seasonal variation allowed to distinguish between different sources for methanol release into the troposphere. Strong evidence for methanol removal via deposition on dew-wetted surfaces is obtained from the comparison of meteorological data with methanol mixing ratios. The mean volume mixing ratio of total methanol was 7.5 nmol mol−1. Mixing ratios ranged from 0.03 up to 45 nmol mol−1.