Atmospheric circulation dynamics linked with prominent discharge events in Central Europe

Abstract

Abstract Studies on links between flood events and atmospheric circulation at historical time scales are often constrained by the temporal resolution (monthly or even seasonal) of reconstructed atmospheric pressure fields. Thus, it is necessary to include investigations based on daily resolved data, despite their restricted time spans. In particular, it will be possible to determine circulation pattern sequences preceding prominent discharge events identified from various gauged time series. Based on daily 500-hPa geopotential height fields from the NCEP/NCAR re-analyses, major large-scale circulation pattern sequences for such discharge events in Central Europe are determined by EPCA techniques (principal component analyses extended in the time dimension). Results from different Central European catchment areas are put together for an overview of the most important sequences during winter and summer. They are finally compared with previous results from monthly analyses of historical data.