The aim of this study was to determine, by use PCA analysis, the impact of meteorological elements on the PM₁₀ concentration on the example of the mountain valley. Daily values of selected meteorological elements, measured during a ten-year period in the spring, summer, autumn and winter, obtained from the meteorological station in Nowy Sącz, were adopted as variables explaining PM₁₀ concentration. The level of PM₁₀ was significantly affected by the maximum, minimum and average temperature in autumn, winter and spring. In summer the average and maximum temperature was significant. In winter, the first principle component mainly consisted of the combination of the average and maximum wind speed. The second principal component in spring, summer and autumn was the combination of the wind speed (average and maximum), but in winter humidity and atmospheric pressure seemed to be significant. The third principal component, in terms of strength of impact, was humidity in spring, the combination of humidity and minimum temperature in summer, and precipitation in autumn. In winter, the highest PM₁₀ concentrations were observed during the non-directional, anticyclonic wedge conditions. Three principal components were distinguished in this situation: temperature (average, maximum and minimum); the combination of humidity and wind speed and precipitation.

Urban development causes multiple water losses. Some of them may be ignored but some could have a huge influence on the whole catchment, including soil drought. As urban sprawl rises, space for unaffected infiltration and retention is increasingly limited. The objective of this study was to backcast and to estimate water-retention loss due to urbanization during the period of 1990–2018. We used landcover data, meteorological and hydrological data and data on soil water-holding capacity. Water-retention loss was expressed as soil water retention capacity loss, net precipitation loss and total sum of precipitation loss. Historical change in urban extension has led to large impacts on the hydrological cycle of the study area. Progressive urban development caused water-retention losses which range from 3.380 to 14.182 millions of cubic meters—depending on the methodology used. Hydrological analysis showed the lack of a significant trend (decrease trend) of low flow which is caused by the high percentage of natural land use in the upper part of catchment. Our results show that backcasting of water retention change using CLC data (a) brings new and plausible data on retention loss, (b) is possible to replicate and (c) data used are common and easy-to-get.

Designing hydraulic structures, such as culverts, bridges, weirs, and check dams, while planning new flood inundation areas, needs correct assessment of design discharges. In gauged catchments with long time series of discharges, statistical methods are commonly used based on fixed theoretical distributions and on empirical distributions. However, in ungauged catchments, this approach is not possible. In addition to more advanced methods, which are used today, e.g., rainfall–runoff models, much more simple approaches are still needed based on regionalization and empirical models. Thus, the objective of this work is to develop a new empirical model for calculating peak discharge expressed as the median of annual peak discharge (Q_MED). The innovative aspect of this paper is the use of a new parameter, named landscape hydric potential (LHP), as a descriptor of water storage in catchments. LHP has a crucial role as the descriptor of water storage in catchment and, thus, it has an influence on forming discharges. The work was done in the Upper Vistula basin in the Polish Carpathians. This study was carried out in mountain catchments located in the Upper Vistula basin, in the south part of Poland in in the Polish Carpathians. Results show that the proposed model could provide appropriate calculations in changing climate conditions, as well as when land use is changed. The proposed model is simple and effective; for calculating Q_MED, it needs only two parameters: catchment area and LHP. Since the model has a significant and high correlation coefficient, it could be used for assessing of Q_MED in ungauged mountain catchments. The determined form of the empirical equation finds application in the entire Upper Vistula basin, for catchments with a surface area from 24 km² up to 660 km².

The problem of precipitation deficits constitutes an issue that is significant on a global, re-gional, and local scale, particularly in the aspect of climate warming. The purpose of this research was to determine the amount, frequency and trends of precipitation deficits in the cultivation of winter wheat in central and eastern Poland, over a period of fifty years (from 1971 to 2020). This study used the values of average monthly air temperatures, as well as monthly total precipitation, decadal precipitation needs of winter wheat within central and eastern Poland. Based on the performed research, both spatial and temporal differences were observed in the scope of the amount and frequency of precipitation deficits in the cultivation of winter wheat. The lowest risk of precipitation deficits was found in May (from 15% to 32%), which is a critical month in the cultivation of this plant in Poland, while the highest risk of precipitation deficits was observed in June (from 22% to 56%), which is an unfavourable phenomenon, because winter wheat is in the so-called grain filling phase since mid-June. It was also found that there is a statistically significant upward trend of the winter wheat’s precipitation needs in April, June, and July. An increase in the inflow of warm and dry air masses from the southern sectors was one of the factors impacting the amount and frequency of precipitation deficits in the cultivation of wheat. The problem of climate warming that has been increasing in recent years, and – as a consequence – an increase in precipitation deficit during the growing season of plants, demonstrate the need for further research in this scope.

Structure of radiation balance in diverse types of relief. The article presents the results of research on the structure of radiation balance in the full spectrum in diverse types of relief. The study was carried out on the Kraków-Częstochowa Upland (Poland). The varying terrain, its forms, expositions and slopes, large denivelations, and the varying land cover and land use make this small area very diverse as far as radiation conditions are concerned. On the basis of an actinometrical study the structure of radiation balance was assessed in two distinct morphologic terrain forms: the bottom of the valley and the plateau. It was proved that the global solar radiation (K↓) reaching the bottom of the valley in one year was on average 15% lower than the solar energy reaching the plateau. The all wave radiation balance (Q*) at the bottom of the valley was 16% less than on the plateau. The result of complex radiation conditions in the diversified relief was the occurrence of a mosaic of plant groups with distinct requirements.