Photochemical Ozone Formation in the Atmosphere over Southern England

Abstract

ATKINS et al.¹ present evidence of photochemical ozone formation in the atmosphere over southern England. When, however, the diurnal ozone variation is carefully examined, some doubt may be felt whether all the ozone measured was indeed locally generated. The data given by Atkins et al. include thirteen days where pronounced ozone peaks could be observed and in all these cases the maxima occurred in the late afternoon, between 1600 and 1700 BST. These late afternoon maxima are not in accord with the predicted diurnal variation of photochemically produced ozone; the daily maxima should appear between 1200 and 1400 local standard time, when the combination of high insolation and temperature leads to enhanced ozone production².