5. CONCLUSIONS AND RECOMMENDATIONS
1. Data for 1996 were received by the European Commission from 14 Member States.
13 Member States provided information on ozone concentrations for a
total of 836 monitoring stations. Italy provided information too late to be included fully
in this report. From France no information was received.
2. The spatial coverage and quality documentation of the data need further improvement.
Depending on the local situation, the ozone monitoring stations are characterized as rural, urban, street or other (e.g. industrial). Further work on a harmonized classification system is needed.
The present subset of rural stations is not representative for the land area of the EU: the subset is estimated to cover only 40-50%. The subset of urban stations is insufficient to estimate the exposure of the population living in all cities with more than 25 000 inhabitants: the urban subset covers at most 30% of the urban population.
Spatial coverage and documentation of the monitoring data quality need
improvement if the level of protection of human health and ecosystems in Europe to
elevated ozone levels is to be fully assessed. Member States are encouraged to reconsider
their ozone measuring networks in the light of the spatial coverage of ozone monitoring
stations. It is recommended to improve the documentation on the representativity and on
the surrounding of the existing stations.
3. The threshold value set for the protection of human health was exceeded substantially in all Member States.
The threshold value of 110 µg/m3 (8h-average) was exceeded
substantially (in about 25% of the reported exceedances the 8h-average
concentrations exceeded 165 µg/m3). The subset of urban stations is assumed to
give representative values for the exposure of an urban population of approximately 65
million people. 12% of this population (7.8 million people) is not exposed to ozone levels
exceeding the threshold whereas 6% (3.9 million people) is exposed to exceedances during
more than 50 days. The number of days with at least one exceedance observed at the
reporting stations within a Member State ranges from 12 (Ireland) to 277 (Spain).
4. The threshold values set for the protection of vegetation were exceeded substantially and in almost all EU Member States.
The threshold value of 65 µg/m3 (24h-average) is reported to have been exceeded substantially (by up to a factor 3), widely (in all reporting Member States) and frequently (several Member States report exceedances during more than 150 days at some of their stations). Exceedances during more than 150 days are estimated for more than 31% of the area for which the subset of background stations report representative values. The threshold value of 200 µg/m3 (hourly average) is exceeded largely and widely (reported by 10 (out of 13) Member States) on a limited number of days.
5. The threshold value for information of the population was exceeded in almost all EU Member States during a limited number of days.
Exceedance of the information threshold value of 180 µg/m3
(1 h average) was reported for stations in 12 (out of 13) Member States. For two stations
an exceedance of the warning level of 360 µg/m3 (1h average) was reported.
6. It is recommended to improve the reporting of ozone precursors (NOx, NO2 and VOC).
NOx measurements should be co-located with the ozone monitoring stations as NOx can be used as an indicator of the station representativeness. Moreover, precursor concentrations will be needed for testing of compliance with VOC and NOx emission reduction programmes.
Anderson H.R., Spix C., Medina S., Schouten J.P., Castellsague J., Rossi G., Zmirou D., Touloumi G., Wojtyniak B., Ponka A., Bacharova L., Schwarts J. and Katsouyanni K. (1997) Air pollution and daily admissions for chronic obstructive pulmonary disease in 6 European cities: results from the APHEA project. Eur. Respir J. 10, 1064-1071.
Barrett K. and Berge E. (eds.) (1996) Transboundary air pollution in Europe. Part 1: Estimated dispersion of acidifying agents and of near surface ozone. EMEP/MSC-W Report 1/96. The Norwegian Meteorological Institute, Oslo, Norway.
Beck J.P. and Krzyzanowski M. (1997) Tropospheric ozone in the European Union. "The consolidated Report", Commission of the European Community, Brussels, Belgium. Available on Internet from European Environment Agency.
Borrell, P. and van den Hout D. (1995) Tropospheric ozone - a review of current understanding. Doc.Ref XI/363/95, European Commission, Brussels.
Bull K.R. (1991) The critical load/level approach to gaseous pollutant emission control. Environ. Pollut., 69, 105-123.
De Leeuw F., Sluyter R. Van Zantvoort E. and Larssen S. (1995) Exceedance of Ozone threshold values in the European Community in 1994. Summary based on the information reported in the framework of the Council Directive 92/72/EEC on air pollution by ozone. European Topic Centre on Air Quality.
De Leeuw F., and Van Zantvoort E. (1996) Exceedance of Ozone threshold values in the European Community in 1995. Summary based on the information reported in the framework of the Council Directive 92/72/EEC on air pollution by ozone. EEA-Topic Report 29/1996, European Environment Agency, Copenhagen.
Derwent, D. and van den Hout D. (1995) Computer modelling of ozone formation in Europe. Doc.Ref XI/364/95, European Commission, Brussels.
EC (1994). Information Document concerning Air Pollution by Ozone - Overview of the situation in Europe during Summer 1994. European Commission, Brussels.
Gilbert R.O (1987) Statistical methods for environmental pollution monitoring. Van Nostrand Reinhold, New York.
Hjellbrekke A.G.(1996) Ozone Measurements 1993-1994, EMEP/CCC report 1/96, NILU, Kjeller, Norway.
Roemer M. (1996) Trends of tropospheric ozone over Europe. Thesis, University of Utrecht.
Sartor F., Demuth C., Snacken R. and Walckiers D. (1997) Mortality in the elderly and ambient ozone concentration during the hot summer, 1994, in Belgium. Environmental Research, 72, 109-117.
Sluyter R. and van Zantvoort E. (1996) Information document concerning air pollution by ozone. Overview of the situation in the European Union during the 1996 summer season (April - July). EEA Topic Report 29/1996, European Environment Agency, Copenhagen.
Van Zantvoort E. and Sluyter R. (1996) Annex to the report: Exceedance
of Ozone threshold values in the European Community in 1994. Summary based on the
information reported in the framework of the Council Directive 92/72/EEC on air pollution
by ozone. European Topic Centre on Air Quality.
For references, please go to http://www.eea.europa.eu/publications/P1I92-9167-076-6/page006.html or scan the QR code.
PDF generated on 24 Jan 2017, 08:43 AM