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Using a Hybrid Method for Control the Storage Capacity of the Dam Reservoir
Pospíšilík, Šimon ; Kozel, Tomáš (referee) ; Menšík, Pavel (advisor)
Bachelor thesis is focused on the selection of a suitable input regional climate model into the Hybrid method for the control of the storage function of water reservoirs. This control method is based on a suitable combination optimization method with the Support vector machines method. Selecting a suitable regional climate model is done by simulating the control of the storage function of water reservoirs Vír I in program Microsoft Exel. The simulation results of the hybrid control method are compared with other control methods. These methods are Adaptive control, Dispatcher graph, and control to Improved outflow.
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New parameterizations in the RegCM model
Pitaš, Ondřej ; Belda, Michal (advisor) ; Karlický, Jan (referee)
This thesis compares new physical parameterizations in the regional climate model system RegCM with the standard settings used at the Department of Atmospheric Phy- sics and observed climatic conditions. The first part is dedicated to the description of individual parameterizations and to the essential introduction to the RegCM model. In addition, model preprocessing and running simulations are discussed. The simulations were conducted over Europe domain for the ten-year period (1990-1999) with five dif- ferent model settings. Holtslag PBL(Holtslag, 1990) type boundary layer scheme, Grell cumulus convention scheme over land and ocean and Explicit moisture scheme (SUBEX; Pal et al 2000) were used in the reference simulation. In the conducted simulations, the following physical parametrizations were used separately: UW PBL (Bretherton and McCaa, 2004) boundary layer scheme, Explicit moisture Nogherotto/Tompkins mois- ture scheme, Tiedtke (1996) and Kain-Fritsch (1990) & Kain (2004) cumulus convention schemes over land and ocean. None of the new physical parameterizations showed impro- vements over standard setting in all analyzed variables at the same time. Precipitation is best described by reference simulation as well as by simulations with UW PBL and Kain- Fritsch & Kain parametrization type. Kain-Fritsch...
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Spatial variability of precipitation annual cycles
Slezáčková Zíková, Naděžda
Title: Spatial variability of precipitation annual cycles Author: Naděžda Zíková Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: Jaroslava.Kalvova@mff.cuni.cz Abstract: This thesis enquires into the spatial variability of precipitation annual cycles and its representation by regional climate models. Goal is to find suitable metrics that could describe spatial character of the precipitation field and con- sequently evaluate model results. For complete understanding the issue, there is an introduction to modeling with regional climate models and also parameters of the precipitation in the Czech Republic. The main part of the thesis is an application of different methods of descripiton on the results of the regional cli- mate models (including the Czech model ALADIN) and CRU data. Results of the models are compared to observed data transferred into the regular grid. Each method is applied on the model results and assessed with regard to advantages and disadvantages. The metrics that were found useful are recommended for the further evaluation of the spatial variability of precipitation annual cycles. The ALADIN model seems to be quite successfull, weak points are only modelling of the precipitation in spring and the effect...
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New parameterizations in the RegCM model
Pitaš, Ondřej ; Belda, Michal (advisor) ; Karlický, Jan (referee)
This thesis compares new physical parameterizations in the regional climate model system RegCM with the standard settings used at the Department of Atmospheric Phy- sics and observed climatic conditions. The first part is dedicated to the description of individual parameterizations and to the essential introduction to the RegCM model. In addition, model preprocessing and running simulations are discussed. The simulations were conducted over Europe domain for the ten-year period (1990-1999) with five dif- ferent model settings. Holtslag PBL(Holtslag, 1990) type boundary layer scheme, Grell cumulus convention scheme over land and ocean and Explicit moisture scheme (SUBEX; Pal et al 2000) were used in the reference simulation. In the conducted simulations, the following physical parametrizations were used separately: UW PBL (Bretherton and McCaa, 2004) boundary layer scheme, Explicit moisture Nogherotto/Tompkins mois- ture scheme, Tiedtke (1996) and Kain-Fritsch (1990) & Kain (2004) cumulus convention schemes over land and ocean. None of the new physical parameterizations showed impro- vements over standard setting in all analyzed variables at the same time. Precipitation is best described by reference simulation as well as by simulations with UW PBL and Kain- Fritsch & Kain parametrization type. Kain-Fritsch...
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Using a Hybrid Method for Control the Storage Capacity of the Dam Reservoir
Pospíšilík, Šimon ; Kozel, Tomáš (referee) ; Menšík, Pavel (advisor)
Bachelor thesis is focused on the selection of a suitable input regional climate model into the Hybrid method for the control of the storage function of water reservoirs. This control method is based on a suitable combination optimization method with the Support vector machines method. Selecting a suitable regional climate model is done by simulating the control of the storage function of water reservoirs Vír I in program Microsoft Exel. The simulation results of the hybrid control method are compared with other control methods. These methods are Adaptive control, Dispatcher graph, and control to Improved outflow.
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Analysis and assessment of ensemble simulations of regional climate models in Europe for selected scenarios of greenhouse gases
Kluková, Zuzana ; Halenka, Tomáš (advisor) ; Belda, Michal (referee)
An analysis of the air temperature and precipitation for historical and future experiments of regional climate models from Euro-CORDEX activity is presented. A validation of models was performed for the time period 1989 - 2005 using the comparison of model results with E-OBS dataset which represents real values. For this period results show good agreement for temperature, much worse agreement appears for precipitation where their overestimation is more typical. The future evaluation based on the scenarios of greenhouse gases RCP4.5 and RCP8.5 was investigated for periods 2021 - 2050 and 2071 - 2100 in comparison with the period 1971 - 2000 as reference. For the simulations of the future climate we can notice an approximately linear increase of temperatures which is most significant in the northeast Europe. For precipitation models predict their increase in the north Europe and decrease in the south Europe.
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Spatial variability of precipitation annual cycles
Slezáčková Zíková, Naděžda
Title: Spatial variability of precipitation annual cycles Author: Naděžda Zíková Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: Jaroslava.Kalvova@mff.cuni.cz Abstract: This thesis enquires into the spatial variability of precipitation annual cycles and its representation by regional climate models. Goal is to find suitable metrics that could describe spatial character of the precipitation field and con- sequently evaluate model results. For complete understanding the issue, there is an introduction to modeling with regional climate models and also parameters of the precipitation in the Czech Republic. The main part of the thesis is an application of different methods of descripiton on the results of the regional cli- mate models (including the Czech model ALADIN) and CRU data. Results of the models are compared to observed data transferred into the regular grid. Each method is applied on the model results and assessed with regard to advantages and disadvantages. The metrics that were found useful are recommended for the further evaluation of the spatial variability of precipitation annual cycles. The ALADIN model seems to be quite successfull, weak points are only modelling of the precipitation in spring and the effect...
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Regional Climate Modeling
Belda, Michal ; Halenka, Tomáš (advisor) ; Huth, Radan (referee) ; Metelka, Ladislav (referee)
Regional climate models are commonly used for downscaling global climate simulations to the regional scale using nested limited-area models. One of the main goals of this work was the application of regional model RegCM in very high resolution for the region with complex topography in the framework of EC FP6 project CECILIA. RegCM was employed to downscale climate change scenario simulations performed by ECHAM5 model according to the IPCC A1B emission scenario for Central and Eastern Europe in 10km resolution. Validation of model performance, assessed by nesting RegCM in ERA-40 reanalysis, shows improvement of regional climate patterns mainly in mountainous areas. Temperature is well represented with mostly cold bias around -1 žC. Precipitation is affected by large biases around 80 %, in mountainous areas up to 400 % overestimation in winter. Downscaled climate change signal shows average warming 0.51.5 žC in period 20212050 and 24 žC in period 20712100. Precipitation changes are mostly within ±0.5 mm/day. RegCM3beta version with adjusted precipitation scheme parameters shows improvement of the precipitation bias, difference in climate change is rather negligible. Experiments with different convection schemes of RegCM in a case study for Africa performed in the framework of CORDEX project are...
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Statistical correction of daily precipitation sums from climate models
Hnilica, Jan ; Chára, Zdeněk (advisor) ; Jan, Jan (referee)
Climate change prediction and evaluation of its impact currently represent one of the key challenges for the science community. Regional climate models (RCM) have been recently established as a main source of the data for climate change assessment studies. Nevertheless, RCM outputs suffer from systematic errors caused primarily by their low spatial resolution and cannot be used directly without any form of bias correction.
The bias correction is an actual topic in climatology and several correction methods were developed, ranging from the simple additive method to more advanced approaches (e.g. quantile mapping). However, despite this progress, the bias correction methods suffer from several difficulties, which bring another source of uncertainty into the climate change impact assessment studies.
This thesis is focused on two problematic points connected with the bias correction of daily precipitation data. The first one is a non-stationarity between calibration and application periods. New correction methods are developed, showing an increased resistance to non-stationary conditions. The second problem is related to the correction of a dependence (i.e. correlation and covariance) structure of multivariate precipitation data. A new procedure is proposed, correcting the complete dependence structure of the model data. All newly introduced methods are validated using measured and RCM-simulated data; the validation demonstrates their suitable applicability.
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