| Abstract: | Sea bottom changes in the cross-shore direction have been analysed. The cross-shore profile, as a major factor of beach configuration, has been presented schematically as a superposition of a basic curve reflecting the mean layout and slope of the shore given by Dean's function
and superimposed various bars, troughs, berms, etc. depicting local characteristic features of the profile.The local features of the profile have been analysed by use of one- (1-D) and two-dimensional (2-D) empirical orthogonal functions.On the basis of field observations and measurements the parameter A has been presented as a function of time. Three time scales have been distinguished (short, seasonal and long-term) with respect to which more or less regular changes of the parameter A occur. The modified parameter A was applied to two different field sites, namly Lubiatowo, Baltic Sea (Poland) and Gold Beach, Black Sea (Bulgaria). It has been found that in extreme cases the parameter A can vary in time by a factor of two, or more, for the same grain size distribution. |
