Impact of hydrometeorological conditions on the Southern Baltic cliff coast development in the annual and long-term weather cycle

To determine the specificity of functioning the Southern Baltic coasts, it is necessary to identify the hydrometeorological conditions that have the greatest effect on the dynamics of geomorphological processes in detail. For the offshore coastal zone, it is important to determine temporal variability (including trend, cyclicality and seasonality) and spatial diversity (i.e. for cliff and dune coasts) of occurrence of main hydrometeorological and geomorphological processes and events. Among hydrometeorological and geomorphological factors - which are decisive for violent, intense and sometimes irreversible changes in the natural environment - extreme events play an important and sometimes dominant role (Tylkowski, Hojan 2018).

Geomorphological changes of the cliff coast depend mainly on the dynamics of marine and slope erosion. The high sea level that occurs during storm swells and intense precipitation lead to the transformation of the cliff coast, which is seen in the retraction of the cliff crown, among others (Kostrzewski et al. 2015).

The purpose of the work was to determine the temporal variability of hydrometeorological conditions, which have the greatest effect on the dynamics of the erosion of the cliff shores of the Wolin island. Hydrometeorological conditions from 1985 – 2019 period were compared to the annual measurements of the cliff crown retraction, which were carried out on 5 test sections in the coastal zone of the Pomeranian Bay on the island of Wolin. The work indicates the occurrence of above-average and extreme hydrometeorological events that potentially favoured the occurrence of erosive processes, e.g. mass movements, slopewash and aeolian erosion.

Using ARIMA modelling, time decomposition of hydrometeorological conditions was made and their short-term forecasts were formulated. The study determined non-seasonal and seasonal parameters that determine the occurrence of current and future meteorological and marine conditions. What is more, spatial differences in the scope of identification of the features of the analysed time series, estimation of parameters of selected models and the formulated forecast are indicated (Tylkowski, Hojan 2019).

 

 

References

Tylkowski J., Hojan M., 2018. Threshold values of extreme hydrometeorological events on the Polish Baltic coast. Water 10(10), 1337. doi:10.3390/w10101337

Kostrzewski A., Zwoliński Z., Winowski M., Tylkowski J., Samołyk M., 2015. Cliff top recesion rate and cliff hazards for the sea coast of Wolin Island (Southern Baltic). Baltica 28(2): 109-120. doi:10.5200/baltica.2015.28.10

Tylkowski J., Hojan M., 2019: Time decomposition and short-term forecasting of hydrometeorological conditions in the South Baltic coastal zone of Poland. Geosciences 9(68). doi.org/10.3390/geosciences9020068