EUROTRAC. Teilprojekt: TRACT. Ausbreitung von Spurengasen ueber orographisch strukturiertem Gelaende Abschlussbericht

Special field measurements of air pollutants during the international TRACT campaign (Transport of Air Pollutants over Complex Terrain) in September 1992 were performed in the so-called Nested Area. The experimental activities covered - the quality control (Quality Assurance) of all trace-gas monitors operating in the Nested Area of all participating institutions, - the study of the transport of air pollutants (Ozon, CO, SO_2) along a traverse of temporary measuring stations from the Upper Rhine Valley to the summit of the Black Forest. The mean ozone concentration at the summit is 2.5 times the one in the Rhine Valley, -the measurements of the diurnal variations of the vertical ozone profiles and meteorological variables up to 1000 m altitude. From the vertical ozone profiles reliable estimates of the height of the nocturnal inversion layers can be made. Within the nocturnal inversion layer in the Upper Rhine Valley ozone is rapidly depleted in the evening hours by dry deposition to the ground and by chemical reactions with NO, - comparative measurements of the vertical turbulent ozone flux from which a mean diurnal maximum value of the dry deposition velocity on gras of 0.33 cm s"-"1 was calculated. (orig.)Available from TIB Hannover: F95B2535+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman