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Use of machine learning methods for satellite data processing
Doležalová, Anežka ; Pišoft, Petr (advisor) ; Piskala Gvoždíková, Blanka (referee)
Meteorological features, such as clouds, can be observed in 2 ways - from ground stations and, more recently in the last decades, by distance methods. The fact that the two views mentioned are different makes it not easy to compare them. In our work, we use MSG data, such as level 1.5 data and NWC SAF product cloud type, and cloud determination at ground stations by observers from CHMI. Based on these data, we build ML models that best determine from the input satellite data the categories that would be observed by the ground-based observer. It is necessary to select the appropriate model type for this task, set the most suitable parameters and also deal with the imbalanced representation of the different meteorological phenomena and associated cloud categories.
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Vertical temperature profile in atmospheric boundary layer
Gvoždíková, Blanka ; Pešice, Petr (advisor) ; Sedlák, Pavel (referee)
Submitted bachelor thesis discusses the issue of the atmospheric boundary layer. First of all, it addresses the boundary layer's thermal characteristics which are very variable near the Earth's surface. For this purpose we have chosen the observatory in Kopisty near Most where a tower meteorological measurement is performed. In addition the air temperature measurements from Milešovka observatory were included to a dataset, too. It is assumed that this mountain weather station due to its position can represent conditions of the free atmosphere. But if we compare some thermal characteristics of the air at different height levels, we'll figure out that the air temperature measurements at Milešovka are highly influenced by radiation balance of the Earth's surface. Despite this fact, the analysis of air layer between Kopisty and Milešovka gives an idea of a continuous-time behavior of air temperature characteristics. This bachelor thesis describes in detail the air temperature variations and the temperature lapse rate variations in several height levels, the variability of thermal stratification or the incidence and extent of air temperature inversions.
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Relationship among moisture flux anomalies, extreme precipitation, and floods in central Europe
Gvoždíková, Blanka
Floods associated with extreme precipitation are one of the most serious natural hazards, which produce substantial human and socio-economic losses in central Europe. One way to reduce the impact of flooding is by increasing preparedness with better flood forecasts and warnings, which is not possible without a proper understanding of physical processes leading to a flood hazard. However, frequent research on floods in relation to causal precipitation and synoptic conditions is usually carried out regionally, although some events often affect areas of a size of entire countries or even larger. The thesis was focused exactly on these large-scale precipitation and flood events that occurred in the second half of the 20th century and then until 2013, for which the size of the affected area is as crucial in the extremity assessment as the magnitude of flood discharges or precipitation totals. The extremity indices used for the assessment of extreme precipitation and flood events connected both aspects. The larger area of interest defined within central Europe allowed examining the spatial structure of events, the differences between them, and their relation to conditions in the atmosphere. To connect the extremes of precipitation with extremes in atmospheric conditions, the causal circulation was...
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A climatological view of atmospheric fronts
Švábek, David ; Huth, Radan (advisor) ; Gvoždíková, Blanka (referee)
This bachelor thesis is focused on a climatological view of atmospheric fronts, which in middle latitudes greatly determine weather and its changes. Scientific literature is reviewed in the text, accompanied by manifestations of atmospheric fronts in a global and local scale for the areas of western and especially central Europe, whereas connection with temperatures, precipitation and other meteorological elements and it's long-term changes are emphasised. Further, the thesis is focused on problems connected with atmospheric fronts detection which is directly related to the most common places of occurence. The objective of the practical part is an analysis of the atmospheric fronts passages over the Praha-Ruzyně meteorological station during twenty year period from 1. 12. 2000 to 30. 11. 2020 with emphasis on winter and summer months. Key words: atmospheric fronts, climatology, temperature, precipitation, climate variability
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Relationship among moisture flux anomalies, extreme precipitation, and floods in central Europe
Gvoždíková, Blanka ; Müller, Miloslav (advisor) ; Nissen, Katrin (referee) ; Wypych, Agnieszka (referee)
Floods associated with extreme precipitation are one of the most serious natural hazards, which produce substantial human and socio-economic losses in central Europe. One way to reduce the impact of flooding is by increasing preparedness with better flood forecasts and warnings, which is not possible without a proper understanding of physical processes leading to a flood hazard. However, frequent research on floods in relation to causal precipitation and synoptic conditions is usually carried out regionally, although some events often affect areas of a size of entire countries or even larger. The thesis was focused exactly on these large-scale precipitation and flood events that occurred in the second half of the 20th century and then until 2013, for which the size of the affected area is as crucial in the extremity assessment as the magnitude of flood discharges or precipitation totals. The extremity indices used for the assessment of extreme precipitation and flood events connected both aspects. The larger area of interest defined within central Europe allowed examining the spatial structure of events, the differences between them, and their relation to conditions in the atmosphere. To connect the extremes of precipitation with extremes in atmospheric conditions, the causal circulation was...
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Extremity of flood between Western and Central Europe
Gvoždíková, Blanka ; Müller, Miloslav (advisor) ; Jeníček, Michal (referee)
The presented diploma thesis deals with identification and evaluation of extreme trans-basin flood events on the border between Western and Central Europe in the period 1950-2010. We can describe each flood event by a set of time dependent mean daily discharge peaks. Selected floods are evaluated by several extremity indices which consider both the intensity and the spatial extent of flooding. When comparing the result lists of extreme floods, it was found that the results are not prone to changes in the design of the area parameter. However, using the index with a higher flood discharge limit the ranking of floods changes significantly. At the same time, we detected an increase in proportion of floods of warmer half-year. Since the affected area is much greater in the case of floods of colder half-year, these events still predominate in the lists. The overall concept of seasonality and inter-annual variability of extreme flood events on the border between Western and Central Europe corresponds to a combination of information from different parts of the area. The resulting seasonality is a good example, as it reflects both floods of colder half-year mainly relating to western part of the area and floods of warmer half-year occurring rather in the east. Keywords: flood, Western Europe, Central...
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Vertical temperature profile in atmospheric boundary layer
Gvoždíková, Blanka ; Pešice, Petr (advisor) ; Sedlák, Pavel (referee)
Submitted bachelor thesis discusses the issue of the atmospheric boundary layer. First of all, it addresses the boundary layer's thermal characteristics which are very variable near the Earth's surface. For this purpose we have chosen the observatory in Kopisty near Most where a tower meteorological measurement is performed. In addition the air temperature measurements from Milešovka observatory were included to a dataset, too. It is assumed that this mountain weather station due to its position can represent conditions of the free atmosphere. But if we compare some thermal characteristics of the air at different height levels, we'll figure out that the air temperature measurements at Milešovka are highly influenced by radiation balance of the Earth's surface. Despite this fact, the analysis of air layer between Kopisty and Milešovka gives an idea of a continuous-time behavior of air temperature characteristics. This bachelor thesis describes in detail the air temperature variations and the temperature lapse rate variations in several height levels, the variability of thermal stratification or the incidence and extent of air temperature inversions.
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