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Snow water content modelling in small catchments
Němečková, Klára ; Daňhelka, Jan (advisor) ; Bercha, Šimon (referee)
Title: Snow water content modelling in small catchments This work deals with modeling of amount of snow cover, snow water equivalent, respectively, on an experimental catchment in the Jizerské hory Mts. Measuring and modelling of the snow cover is an important part of water management practice from the perspective of reservoir operation and flood management. The first part of this thesis describes physical-geographical characteristics of the Jizerské hory Mts.especially from the climatological and hydrological point of view but also other charakteristics and conditions that may affect the dynamic of snow accumulation and melting are described with detailed focus on the experimental catchment of Černá Desná river - Jezdecká. Two modelling approaches were applied to simulate snow water equivalent (SWE) based on observed precipitation and temperature. Beside the well knowen SNOW17 model a simple method based on heat index was developed in this work and its parameters were calibrated based on measured timeseries of daily average air temperature, daily precipitation and observed SWE for winter periods 2001 to 2009. Both methods provided reasonably accurate estimates of SWE over the tested period, however it was found that the results for winters with extreme conditions (very warm or very cold) are less...
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Influence of spatial snow distribution on flood course
Kučerová, Dana ; Jeníček, Michal (advisor) ; Langhammer, Jakub (referee)
For the purpose of hydrological forecasting on mountains' and sub-mountains' rivers is important knowledge of distribution of snow water equivalent in the watershed. Submitted thesis therefore deals with comparison of 9 interpolation methods in terms of quality of their forecasting when predicting snow depth and snow water equivalent in watershed Bystřice (127,6 km2 ), which is situated in the northwest of Bohemia in the Ore mountains. Point data of snow depth and snow water equivalent used in interpolation were sampled during an off- road measuring in 17. 2. 2010 at the 14 snow sampling locations. The interpolation methods were: (1) Thiessen's polygons, (2) inverse distance weighting, (3) global polynomial (4) local polynomial (5) radial basis functions, (6) ordinary kriging, (7) cokriging, (8) residual kriging and (9) orographic interpolation. Independent variable-altitude used in the calculation of snow depth and snow water equivalent was used only in the last three listed methods. Predictive ability of interpolation methods was evaluated by using cross-validation and visual comparison of predicted maps. The best prediction ability was provided by residual kriging and orographic interpolation. The geostatistical methods were next in the order. The method of Thiessen's polygons and inverse distance...
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Effect of vegetation on snow accumulation and snow melt
Pevná, Hana ; Kocum, Jan (referee) ; Jeníček, Michal (advisor)
Effect of vegetation on snow accumulation and snow melt Abstract: This bachelor thesis analyzes the impact of physical-geographic factors on the physical properties and characteristics of the development of snow cover. Results published in the literature are compared with those obtained from experimental measurements in the upper Byst ice River basin in the Ore Mountains during the winter 2009/2010. The paper compares the evolution of snow cover for the actual land cover, forest and open areas. The research of literature and research conducted in the Ore Mountains proved that vegetation significantly affects accumulation and melting of the snow. The process of accumulation in the forest is influenced by snowfall interception in the treetops. Melting snow in a forest area slowed absorption and reflection of sunlight in the treetops. The bachelor thesis demonstrates that in the open areas the snow melted faster than in the forest growth. Keywords: snow cover, snow water equivalent, vegetation, Ore Mountains
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Use of remote sensing data for snow water content determination
Špátová, Zuzana ; Spazierová, Kateřina (referee) ; Kolář, Jan (advisor)
Use of remote sensing for snow water content determination Abstract The aim of this diploma thesis is an integration of remote sensing to snow water equivalent measurement in Czech Republic conditions. The summary of present information of snow parameters retrieval is presented. For snow water equivalent obtaining, radar differential interferometry technique was chosen. The technique was carried out with seven ERS-2 radar images. The result of processing was finished after coherence images creation because of low coherence value at all interferometric pairs. The low coherence values did not enable next processing. Terms of the negative result are discussed. In the second part of the thesis, connection between snow characteristics and radar backscattering is searched. Dependence between snow moisture and backscattering is demonstrated. Factors, which impact values of backscattering and correlation with snow parameters, are discussed. In order to obtain snow water equivalent, the processing of remote sensed data was carried out for the first time in Czech Republic region. Therefore the negative result is still valuable information. Keywords: snow cover, snow water equivalent, remote sensing, radar interferometry
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Seasonal snow accumulation in the mid-latitude forested catchment
Šípek, Václav ; Tesař, Miroslav
The article deals with the snow cover characteristics (snow depth – SD and snow water equivalent - SWE) concerning the mid-latitude forested catchment. Namely, the influence of forest canopy (spruce and beech forest) and altitude (ranging from 835 m a.s.l. to 1118 m a.s.l.) was investigated. Forest cover was proved to have a significant influence on the snow cover accumulation, reducing the SWE by 48 % on average, compared to open sites. The elevation gradient concerning SWE ranged from 30 to 40 mm and from 5 to 20 mm per 100 m in open and forested sites, respectively. Its magnitude was found to be temporarily variable and positively related to total seasonal snowfall amount. The differences among interception losses, concerning various elevations and forest canopy, were not statistically significant.
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