This article presents the temporal and spatial variability of hydrometeorological conditions conducive aeolian processes on the Southern Baltic coastal zone in Poland. The analysis made use of daily meteorological (wind, temperature, and rainfall) and hydrological (sea level) data from 1961 to 2010. Data for four stations (Świnoujście, Kołobrzeg, Ustka, Hel) were provided by the Institute of Meteorology and Water Management in Warsaw. A time decomposition of hydrometeorological conditions conducive to the initiation and intensification of aeolian processes in the coastal zone was also performed. In addition to their scientific significance, the temporal and spatial conditions for aeolian processes on the Baltic coast of Poland have an essential utilitarian significance. Modern aeolian processes on the Baltic coast limit the development potential of the coastal zone. Aeolian processes have a positive and negative impact on geomorphological transformation of the sea coast. They take part in the reconstruction of the beach and foredunes after storms. In periods between storms, coastal wind is seen to decrease the balance of beach sediments and lowers the beach area. On the other hand, onshore wind favors, among other things, filling of tourist infrastructure and development located at the hinterland of the beach and dunes. Hydrometeorological conditions especially favorable to the intensification of aeolian processes are the main determinants of geomorphological changes in the coastal zone (some of which can be extreme). Temporal and spatial analysis of hydrometeorological conditions conducive to aeolian processes is important for many areas of human activity, especially those concerning protection, management, and development of the coast.

The main aim of this study is to determine the threshold values for extreme sea and weather events on the Polish Baltic coast. The study is based on daily hydrometeorological data on the sea level; air temperature and atmospheric precipitation collected between 1965–2014 from six coastal sites (Świnoujście; Kołobrzeg, Ustka, Łeba, Hel, and Gdynia/Gdańsk). Threshold values for the occurrence of extreme events (with a probability of 10% and 95%, and a return rate of once every 10 years) and exceptionally extreme events (with a probability of 1% and 99%, and a return rate of once every 100 years) were determined using probability distribution and quantile analysis. Hydrometeorological absolute extremes were also determined. The methodology used to determine these extreme events and the time-space analysis of hydrometeorological extremes reveal significant geohazards for the functioning of the Baltic coastal zone, including the erosion of coastal dunes and cliffs and the destruction of technical infrastructure.

The Polish Baltic Sea coast is subject to constant changes as a result of sea erosion on sandy and clayey sections. Sand accumulates only on a few sandy sections of the shore. There are various methods of protection limiting the negative impact of sea waves on the shore. In the city of Rowy, the coast was secured with the use of a comprehensive method (artificial reef, textile tube, spurs, and beach nourishment), which has mitigated the sea’s negative impact. The beach has been widened. The upper part of the beach has been built up to the level of the foredune. Biotechnical protection has not been applied at the border between the beach and the foredune (fascine hurdles from brushwood, sand fences, and branches). This has caused wind blowing of sand from the beach to the forest growing on the foredune. The sand also covered the access road to holiday resorts. This was favored by the strong wind from the sea. Several morphological surveys were carried out, including topographic surveys and sedimentological samplings. The range of sand coverage and types of forms (aeolian shadows and drifts) were determined. Fifty eight samples of sand from various sources were collected for sedimentological analysis. Speed and directions of winds that occurred in 2001–2018 were also analyzed. Three wind speed criteria were distinguished: ≥4 m·s-1, ≥10 m·s-1, and ≥15 m·s-1, responsible for blowing away and transporting material. Results indicate that reconstruction of the beach to the height of the foredune, lack of biotechnical protection, and strong, coastal directions of the wind were the main factors responsible for increased aeolian transport of sand inland. Effects of aeolian processes such as those observed on the beach in Rowy were not observed elsewhere on the Polish coast of the South Baltic Sea, where beach nourishment was also performed.

The article aims to present extreme aeolian processes observed in April 2011 in the fields of the Szamocin municipality in Pojezierze Wielkopolskie (the Great Poland Lakeland). Aeolian erosion of cropland was fostered by strong wind with gusts exceeding 15 m·s−1. The erosion was related to the movement of a deep barometric low from the Norwegian Sea over western Russia (Joachim barometric low). Geomorphological mapping of accumulated sandy aeolian covers was conducted. Morphometric measurements of aeolian covers were made considering their spatial distribution and the thickness of sediments that build them. Samples were collected from sediments to analyze grain size and the volume of deposited sediments was calculated. According to grain size analysis the accumulated fine-grained mineral material was well, moderately well and moderately sorted. The thickness of aeolian covers exceeded the thickness of covers presented in Polish literature so far. Calculations of the total volume of mineral sediment derived from small areas covered with aeolian erosion (a few hectares each) indicate significantly greater volumes than those provided in publications from other research areas in Poland. The described dust storms did not cause much damage in Poland. At the same time (8 April) in northern Germany, a dust storm led to a severe collision on the A19 highway. Eight people died in car accidents and dozens suffered serious injuries.

This article presents an analysis of time-series for hydrometeorological conditions determining the behavior of the natural environment in the South Baltic coastal zone of Poland. The analysis is based on monthly data for average air temperature, total atmospheric precipitation, and average sea level during the 50-year period from 1966–2015 for three coastal stations in Hel, Ustka, and Świnoujście. Time decomposition of these hydrometeorological conditions and formulation of short-term forecasts were carried out using ARIMA modelling. This study identifies the seasonal and non-seasonal parameters that determine both current and future hydrometeorological conditions. Moreover, it indicates the spatial differences among features of the analyzed time-series, estimated parameters of the selected models, and forecasts. The ARIMA models used for the Polish Baltic coastal zone are somewhat spatially homogenous. This is especially true of the models for average monthly air temperature, which are identical across the entire coastal zone (2,0,1)(2,1,0)12. Very similar are the models for average monthly sea level across the central and west coast (1,0,0)(1,1,0)12. The model for the east coast, however, was determined to be slightly different (2,0,2)(2,1,0)12. In contrast to those for air temperature and sea level, the models used for atmospheric precipitation were different for each site. Among the parameters modelled, the effect of AR(p) processes was greater than that of MA(q) processes. The monthly models for Ustka are an example of this: average air temperature (2,0,1)(2,1,0)12, atmospheric precipitation (0,0,3)(2,1,0)12, and average sea level (1,0,0)(1,1,0)12. Time decomposition of extreme hydrometeorological conditions has an important utilitarian significance. The climate of the Polish Baltic coastal zone is getting warmer, the sea level is rising, and the frequency of extreme hydrometeorological events is increasing. Time decomposition of hydrometeorological conditions based on monthly data did not reveal long-term trends. In the last half-century, hydrometeorological conditions have been conducive to erosion of coastal dunes and cliffs. These factors determine changes in the natural environment and limit the development potential of the coastal zone. The time decomposition, modelling, and forecasting of hydrometeorological conditions are thus very important for many areas of human activity, especially those related to management, protection, and development of the coast.