On the Spatial Distribution and Seasonal Variation of Lower-Troposphere Ozone over Europe

• Published in: Journal of atmospheric chemistry 1997-11, Vol.28 (1-3), p.11-28
• Main Authors: Scheel, HE, Areskoug, H, Geiss, H, Gomiscek, B, Granby, K, Haszpra, L, Klasinc, L, Kley, D, Laurila, T, Lindskog, A, Roemer, M, Schmitt, R, Simmonds, P, Solberg, S, Toupance, G
• Format: Article
• Language: English
• Subjects: Boundary layers; Ozone; Photochemicals; Seasonal variations; Seasons; Spatial distribution; Summer; Troposphere; Winter
• ISSN: 0167-7764; 1573-0662
• DOI: 10.1023/A:1005882922435

Surface ozone data from 25 Europeanlow-altitude sites and mountain sites located between79°N and 28°N were studied. The analysiscovered the time period March 1989-February 1993.Average summer and winter O^sub 3^ concentrations inthe boundary layer over the continent gave rise togradients that were strongest in the north-west tosouth-east direction and west-east direction, respectively. WintertimeO^sub 3^ ranged from 19 to 27 ppbover the continent, compared to about 32 ppb at thewestern border, while for summer the continentalO^sub 3^ values ranged between 39 and 56 ppb and theoceanic mixing ratios were around 37 ppb. In the lowerfree troposphere average wintertime O^sub 3^ mixingratios were around 38 ppb, with only an 8 ppbdifference between 28°N and 79°N. For summerthe average O^sub 3^ levels decreased from about 55 ppbover Central Europe to 32 ppb at 79°N. Inaddition, O^sub 3^ and O^sub x^(= O^sub 3^ + NO^sub 2^)in polluted and clean air were compared. Theamplitudes of the seasonal ozone variations increasedin the north-west to south-east direction, while thetime of the annual maximum was shifted from spring (atthe northerly sites) to late summer (at sites inAustria and Hungary), which reflected the contributionof photochemical ozone production in the lower partsof the troposphere.[PUBLICATION ABSTRACT]