Density of air quality monitoring networks in EU15 countries during the period 1996 - 2001 ETC/ACC Technical Paper 2003/5

29 Dec 2003


In the Framework Directive (96/62/EC) and its related daughter directives requirements on the number and siting of air quality monitoring stations is given. It has been suggested that, caused by introduction of the Framework Directive, there is a tendency in air quality monitoring networks towards more urban and less regional background stations. This question is analysed using the information collected under the Exchange of Information Decision and stored in AIRBASE. The situation before and after implementation of the Framework Directive and related daughter directives is analysed by comparing the situations in 1996, 1999 and 2001. In this period an increase in the number of station is seen but, in relative terms, there has been no changes from less rural background station in favour of more urban background stations.

At the end of 2001, the monitoring networks for SO2, NO2 PM10 and lead must have been brought inline with the requirements from the 1st Daughter Directive. Compliance of the networks with the monitoring requirements in 2nd and 3rd Daughter Directive must be realised before end 2002 and 2003, respectively. A further adaptation of networks can not be excluded.

Differences in monitoring strategy and network design between the Member States are visualised by comparing station densities in the various countries. A number of socio-economical and environmental variables are used to express the station density. A large variation in densities is observed. The introduction of the Framework Directive seems not to result in a notable harmonisation of the air quality networks in EU Member States after 1999; this might well be related to the fact that the period 1999-2001 is too short for the reconstruction and/or adaptation of the monitoring networks.

By: Frank de Leeuw and Patrick van hooydonk (RIVM)