caa a22 4500 475823338 CHVBK 20180406123824.0 cr unu---uuuuu 170329e20000901xx s 000 0 eng 10.1023/A:1006349926926 doi (NATIONALLICENCE)springer-10.1023/A:1006349926926 The Role of In Situ Photochemistry in the Control of Ozone during Spring at the Jungfraujoch (3,580 m asl) - Comparison of Model Results with Measurements [Elektronische Daten] [P. Zanis, P. Monks, E. Schuepbach, S. Penkett] A photochemical box model has been used to model themeasured diurnal ozone cycle in spring at Jungfraujochin the Swiss Alps. The comparison of the modelleddiurnal ozone cycle with the mean measured diurnalozone cycle in spring, over the period 1988-1996,shows a good agreement both with regard to the shapeand amplitude. Ozone concentrations increase duringthe daytime and reach a maximum at about 16:00-17:00(GMT) in both the modelled and the mean observed ozonecycle, indicative of net ozone production during thedaytime at Jungfraujoch in spring. The agreement isbetter when the modelled ozone cycle is compared withthe mean measured diurnal cycle (1988-1996) filteredfor north-westerly winds >5 m/s (representative ofregional background conditions at Jungfraujoch). Inaddition to ozone, the modelled diurnal cycle of[HO2] + [CH3O2] also shows rather goodagreement with the mean diurnal cycle of the peroxyradicals measured during FREETEX '96, a FREETropopsheric Experiment at Jungfraujoch in April/May1996. Furthermore, this mean diurnal cycle of the sumof the peroxy radicals measured during FREETEX '96 isused to calculate, using steady-state expressions, therespective diurnal cycle of the OH radical. Thecomparison of the OH diurnal cycle, calculated fromthe peroxy radical measurements during FREETEX '96,with the modelled one, reveals also good agreement.The net ozone production rate during the day-time is0.27 ppbv h-1 from the model, and 0.13 ppbvh-1 from the observations during FREETEX '96. Theobservations and model results both suggest that thediurnal ozone variation in spring at Jungfraujoch isprimarily of photochemical origin. Furthermore, theobserved and modelled positive net ozone productionrates imply that tropospheric in situphotochemistry contributes significantly to theobserved high spring ozone values in the observedbroad spring-summer ozone maximum at Jungfraujoch. Kluwer Academic Publishers, 2000 photochemistry nationallicence tropospheric ozone nationallicence peroxy radicals nationallicence Alps nationallicence lower free troposphere nationallicence Zanis P. CABO, Physical Geography, University of Berne, Switzerland aut Monks P. School of Chemistry, University of Leicester, U.K. aut Schuepbach E. CABO, Physical Geography, University of Berne, Switzerland aut Penkett S. School of Environmental Sciences, University of East Anglia, U.K. aut Journal of Atmospheric Chemistry Kluwer Academic Publishers 37/1(2000-09-01), 1-27 0167-7764 37:1<1 2000 37 10874 https://doi.org/10.1023/A:1006349926926 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1006349926926 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zanis P. CABO, Physical Geography, University of Berne, Switzerland aut NATIONALLICENCE 700 1- Monks P. School of Chemistry, University of Leicester, U.K aut NATIONALLICENCE 700 1- Schuepbach E. CABO, Physical Geography, University of Berne, Switzerland aut NATIONALLICENCE 700 1- Penkett S. School of Environmental Sciences, University of East Anglia, U.K aut NATIONALLICENCE 773 0- Journal of Atmospheric Chemistry Kluwer Academic Publishers 37/1(2000-09-01), 1-27 0167-7764 37:1<1 2000 37 10874 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer