The cyclical nature of hydrological regime of a mountain and upland river in the upper Vistula catchment in the multi-year period of 1984–2012: A potential tool for paleohydrology analysis

Abstract

The study assesses the cyclical nature of occurrences of wet and dry years in the catchment of the Dunajec – to the Nowy Targ-Kowaniec section and the Rudawa – section Balice. The analysis was based on the data of mean daily flows from the multi-year period of 1984–2012. Student's t-test was used in order to demonstrate the differences between the values of flows in dry and wet years. The relationship between the Mean Annual Flow (MAF) flows was determined in subsequent years by using the test of series. The cyclical nature of mean annual flows was examined by using a Fourier series. The probability of occurrence of wet and dry years was estimated by the conditional probability. The analysis showed that the mean annual flows in both catchments varied between dry and wet years. The greatest periodicity of MAF flows occurs in the Rudawa catchment; this can be the result of changing weather conditions determined by the predominant types of atmospheric circulation, as well as by the greater retention capacity of the catchment. The conditional probabilities of the occurrence of dry and wet years varied from 54% to 88%. The highest probabilities occur in the Rudawa catchment, where there is the greatest cyclicality of flows. Another study goal was to conduct an example study for paleohydrologists in analyzing long period times for flood observations of different tributaries, which are feeding the same river treating a time series analysis of flow regimes as a simple paleohydrological tool. As postulated by Gregory and Walling (1973), any study of water and sediment dynamics in the past introduces a promise for future investigations. In that sense, if have a similar case and data used here might be possible to analyze hydrological trends for catchments in the future.