Abstract
The paper presents an objective air quality classification scheme for observed ozone (O 3), nitrogen dioxide (NO 2), sulphur dioxide (SO 2) and particulate matter (PM10) time series in Germany. The classification is based on the medians of daily average concentration and relative daily variation. Six (O 3 and NO 2) and five (SO 2 and PM10) different regimes were identified by means of hierarchical clustering. The stability of the clusters in relation to variable scaling and transformation was ensured by a cross-validation test based on re-sampling. Quick classification rules were developed, which permit a rapid and easy classification of any further observed or modelled annual time series. The climatological properties of the defined regimes were examined in terms of the mean and maximum values, as well as inter-annual, yearly, weekly and daily variability. The polluted regimes are characterised by a pronounced weekly cycle. O 3 and NO 2 classifications agree reasonably well for most stations, but the range of SO 2 and PM10 concentrations is large within specific O 3 regimes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.