Zróżnicowanie i zmienność wieloletnia sezonowości przepływu w wybranych przekrojach wodowskazowych Wisły
Differentiation of river flow seasonality and its multiannual changeability in selected cross-sections on the Vistula river

Summary/Abstract: The aim of the study is to identify the flow seasonality of the Vistula river in 14 water-gauge cross-sections located along the river course (from Skoczów to Tczew). For this purpose, the following characteristics were used: seasonality index (IS), period of seasonal concentration (PK) half-flow date (TPO), and concentration index (GMO). Hydrometric data from the 1951–2016 period were shared by IMGW-PIB. The average time of seasonal concentrations and half-flow dates in the analysed cross-sections occurred in April or May. Along the Vistula river the mean PK and TPO regress towards winter (are earlier and earlier). The average seasonality index is comprised in the range 22–32%, while the values of the concentration index fall into the range 10.0–14.5. The highest IS values characterize the upper part of the river down to the Goczałkowice water-gauge (here it reaches the maximum). Next the IS rapidly decreases, due to the summing of the flows from the Vistula river tributaries varying conditions of flow formation (from Carpathian Mountains and Uplands).

• Details
• Contents