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Changes in runoff from selected glaciated catchments in the Alps
Chytil, Jan ; Jeníček, Michal (advisor) ; Nedělčev, Ondřej (referee)
Glaciers are crucial in alpine regions, especially during the summer months when they supply water to lower-lying regions. However, they are expected to melt more rapidly in the future and glacier water is expected to decline gradually. As a consequence, the seasonality of runoff from glacial catchments will change and the water deficit in the summer months will intensify. The goals of this thesis were (1) to assess the current state of knowledge on the hydrological regime of mountain glacier catchments and its changes, and (2) to evaluate the hydrological regimes of selected mountain glacier catchments in the Alps. Long time series from 5 glacier catchments in the Swiss Alps were used to find trends in monthly runoff. Trends were calculated using the Mann-Kendall trend test and quantified by the Sen's slope estimator. In general, the results indicated that summer flows increased the most in the catchments with the highest percentage of glaciation and also with the highest mean elevation. A decreasing trend in summer flows and an increasing trend in winter flows occurred at stations with low percent glaciation and large catchments area. Catchments with both low percent glaciation and the lowest average elevation were the least subject to trends in both average and extreme flows. Accelerating...
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Runoff development in selected catchments in the Kyrgyz Range, Tian-Shan
Jedličková, Šárka ; Šobr, Miroslav (advisor) ; Janský, Bohumír (referee)
The main objective of this paper was to investigate runoff changes in the catchment Ala-Arca, Alamaedin and Kara-Balta in Kyrgyzstan, as well as change in climate conditions from available stations in the area. The runoff, precipitation, and temperature series were subjected to monthly, seasonal and annual analyses based on available data. Both absolute and relative data homogeneity were verified using statistical tests such as the Mann-Whitney-Pettit test, the SNHT test, and the WiIlcoxon's two- sample test for absolute homogeneity, and the Alexandersson's test for relative homogeneity. The Mann-Kendall test was used to determine the trend in each serie. There were inhomogeneities found in a number of runoff data. In most cases, the changes of rivers Ala-Arca and Kara-Balta were recorded in 1987. Compare to Ala-Arca and Kara-Balta, the changes of river Alamedin were recorded 3 years later, in 1990. There was a positive trend development by the rivers with the glacial-snow regime. However, there was no statistically significant trend for the entire time series. Key words: runoff change, precipitation, temperature, glacial-snow regime, snow-glacial regime, homogenization, Mann-Whitney-Pettit test, trend, Mann-Kendall test, glaciation, Kyrgyzstan, Tien- Shan
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