Application of Dean's curve to investigation of a long-term evolution of the southern Baltic multi-bar shore profile

•We analyse cross-shore bathymetric profiles in Lubiatowo, south Baltic.•Parameter A of the Dean's curve does not reflect multi-bar shore profile evolution.•Shoreline migration is not a reliable shore erosion/accretion indicator.•Nearshore sediment resources are a representative parameter of shore stability.•Dean's approximation may be used in sediment resources calculation.

SummaryThe paper presents the results of studies on the long-term evolution of the multi-bar cross-shore profiles. The analysis is focused on time-dependent variability of shoreline position, a modified parameter A of the conventional Dean's equation and a parameter F describing the amount of nearshore sediment resources in the multi-bar cross-shore profile. The study also deals with interrelationships between these quantities. The analysis is carried out using field data collected at Lubiatowo, Poland, on the dissipative shore, representative for the south Baltic. The considered coastal segment is found to be stable in the long-term scale. The results of analysis show that the parameter A can either increase or decrease together with the shoreline advance. It is concluded that the shoreline position change is a parameter unsatisfactorily representative for behaviour of the seashore. The use of the Dean's approximation for estimation of the sediment resources F on the multi-bar seashore profiles is found reasonable to eliminate the effects of peculiarities of such shores.