Exceedance of EC Ozone Threshold Values in Europe in 1997.

This paper summarises the annual information on ozone monitoring stations and exceedances of ozone threshold values during 1997 transmitted by the Member States of the European Union in the framework of Council Directive 92/72/EEC on air pollution by ozone. In August 1998 information for the calendar year 1997 was received from all Member States and, on a voluntary basis, from 6 other European countries (Switzerland, Czech Republic, Latvia, Norway, Poland and Slovakia). An evaluation of the exceedances and annual statistics for 1997 clearly shows that ozone is a severe, Pan-European problem. The threshold value set for the protection of human health was exceeded substantially and in all reporting countries. The threshold value of daily average concentrations set for the protection of vegetation was exceeded substantially (by up to a factor 3), widely (in all reporting countries) and frequently (at several stations on more than 200 days). The threshold value of hourly average concentrations set for the protection of vegetation was exceeded largely and widely (reported by 10 EU Member States and in three out of the six other European countries) on a limited number of days. The threshold value for providing information to the population was exceeded in 15 countries of which 12 EU Member States during a limited number of days. Exceedance of the threshold value for warning of the population was reported from one station in Greece. [ABSTRACT FROM AUTHOR]