Statistical comparison of European circulation patterns and development of a continental scale classification

Summary

In this paper several circulation pattern classifications developed for different European regions are compared with respect to their mutual dependence. Circulation pattern (CP) classifications – both subjective and objective – for the British Isles, Germany and Greece were considered. Statistical tests were applied in order to investigate the relationships between each pair of CP classifications. It was found that each pair of classifications cannot be considered to be independent. Time dependence in the relationship between CP classifications shows anomalous behavior only when one of the classifications is subjective. This is due to a gradual change in the methodology, and therefore these classifications should be used for climate evolution studies with care. The dependence between each pair of CP classifications was motivation for developing a new CP classification for the whole European continent which is presented. It is shown that for the local precipitation variability almost no information is lost when comparing this new classification with local classifications.