5 
Abstract 
Abstract 
Water bodies with a connection to the open sea are characterised by water 
level fluctuations with a significant tidal proportion. In interpreting such water 
level time series It Is therefore Important to appropriately Isolate the astronomi 
cally caused proportion. Only then, valid conclusions regarding meteorological, 
climatological and hydrological influences or even trends are possible. Not 
least, an analysis of tides allows also for tidal predictions, which, in the form of 
tide tables and, increasingly, digital illustrations, are used by shipping and 
coastal water resources management, to name a few users. Since 1954, the 
levels and times of high and low waters are calculated by the method of “har 
monic representation of inequalities”. The arithmetical operation Is Illustrated in 
detail by the example of a 19-year time series from the gauging station Cux- 
haven, including also illustration of the extension of the procedure to complete 
tide curves. 
Descriptors: Tidal prediction, tide curve, Inequalities