Changes in the Thickness of Ice Cover on Water Bodies Subject to Human Pressure (Silesian Upland, Southern Poland)

Abstract

The paper discusses the reasons behind the variation in the thickness of ice on 39 anthropogenic water bodies located in the Silesian Upland (southern Poland). The studies were conducted over the course of three consecutive winter seasons. The measurements and observations were scheduled every 2 days during the freezing and ablation of the ice, and every 4 days when ice cover was present. Each time the thickness of the ice cover and the snow layer covering it were measured. The results show that the 35 water bodies studied are characterized by a similar—quasi-natural—ice regime, in which ice thickness variation depends mostly on the air temperature and the thickness of the snow layer covering the ice. The ice thickness on those water bodies does not significantly differ from that observed on lakes located in northern Poland, measuring on average from circa 4 to 21 cm, and with maximum thicknesses ranging from circa 14 to 40 cm, depending on the season. Four water bodies are characterized by different ice conditions; in their case the average and maximum ice thickness was significantly lower. In the Niezdara N water body this was caused by the inflow of warmer potamic water (quasi-natural regime), whereas in Pod Borem, Sośnicka, and Somerek it was caused by discharges of warm mine water (anthropogenic regime).

A Comparison of Model Calculations of Ice Thickness with the Observations on Small Water Bodies in Katowice Upland (Southern Poland)

“…Maximum ice thickness values usually occur in the second part of the winter season as a result of the gradual accretion of crystalline ice from below (in the first part of winter) followed by snow ice accretion from above [18,26,56]. The dynamics of both these processes determine the final thickness of the ice cover formed on the water body.…”

“…The studied water bodies emerged as a result of either intentional or unintentional human activities, and are all classified as endorheic and polymictic (Table 1). The selection of water bodies with similar surface areas, volumes, depths, hydrological characteristics, and mixing patterns was dictated by the desire to reduce the number of factors that could affect the thickness of the forming ice cover; water bodies into which warmer mine waters or river waters burdened with thermal pollutants flowed, which could inhibit ice cover development in such small water bodies, were not selected [26,53]. Endorheic and polymictic water bodies with small surface areas and volumes freeze almost simultaneously, which is also reflected in further changes in ice thickness and the ability to conduct objective observations [11,17].…”

“…The thickness of ice forming on water bodies is the result of several natural factors, the most important of which are air temperatures during winter, the location of the water body in question, the amount of heat accumulated in its water and bottom sediments, and the amount of snowfall, which translates into the thickness of the snow cover accumulated on the ice [1,2,4,[10][11][12][13][14][15][16][17][18][19][20]. Additionally, ice thickness may be affected by anthropogenic factors, mainly consisting of thermal pollution (e.g., heated water) and the impact of so-called urban heat islands [18,[21][22][23][24][25][26]. In recent decades, global warming has been considered to have an increasing impact on ice phenomena (including the formation of lake ice covers) [27][28][29].…”

Classification of Water Reservoirs in Terms of Ice Phenomena Using Advanced Statistical Methods—The Case of the Silesian Upland (Southern Poland)

“…A somewhat smaller number of studies touch upon the details related to ice phenomena in lakes and other water bodies during short periods (e.g., a single winter season). In these studies, the main focus has been on the correlation between the average daily air temperature and the rate at which the water body in question freezes or thaws, daily ice cover increments, the analysis of the types of ice that forms, ice cover thermal characteristics, movements and tectonics, impact on lake bed morphology, spatial variations in the thickness of ice cover, and the impact of broadly defined human pressure on ice phenomena [4,[28][29][30][31][32][33][34][35][36][37][38].…”

“…Filling an important research gap in the use of advanced tools of statistical analysis in the study of ice phenomena is of cognitive, methodological, and application importance [3,7,8,27,44]. Knowledge of the phenology of ice phenomena is useful not only for determining climate variability in the region over the past last years: the results of such studies can be successfully used to predict the course of limnic processes (e.g., the variability of mixing processes and thermal and oxygen conditions); this is a new aspect of limnological studies [37]. Identifying the regularities of the development of ice phenomena is important from a cognitive and utility point of view as it can contribute to increased safety in the use of water bodies, which is emphasised in multiple studies pertaining to lakes and anthropogenic water bodies [32,33].…”