The present paper seeks to examine the available information on flow-water levels in Bavaria and Baden-Wurttemberg, in the form of hydrograph fluctuations, on the basis of flow levels recorded in Saxony. Various time-series analysis methods were used in obtaining the measurement data on the Elbe water level at Dresden, which was the site selected for the investigation. Periodic fluctuations with wave lengths of 13.6, 9.7 and 6.8 years were identified using both spectral analysis and auto-correlation analysis. These wave results interfere with each other and overlap with the annual cycle. The underlying reasons for this periodicity are as yet unexplained, though a solar origin cannot be ruled out. Subsequent investigation of the high water levels of August 2002 showed that the 13.6 and 6.8-year periodicities overlapped at that particular time. This overlap led to the increase in amplitude and therefore constituted the reason for the flooding.
展开▼
