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Stochastic Weather Generators and Regional Climate Models: Rivals or Allies?
Dubrovský, Martin ; Štěpánek, Petr ; Meitner, Jan ; Zahradníček, Pavel
The paper demonstrates 'collaboration' between the stochastic weather generator SPAGETTA (WG) and Regional Climate Models (RCM) in analysing impacts of Climate Change (CC). In the first part of the paper, the generator is compared with the ensemble of 19 RCMs in terms of their ability to reproduce 11 spatial temperature and precipitation indices in eight European regions: the indices are based on registering days and spells exhibiting spatially significant occurrence of dry, wet, hot or cold weather, or possible combination of dryor-wet and hot-or-cold conditions. The obtained results indicate that both methodologies provide weather series of comparable quality. In the second part of the paper (which was done only for the Central Europe region), the WG parameters are modified using the RCM-based CC scenarios and the synthetic weather series representing the future climate are produced. This experiment is based on a set of CC scenarios, which consist of changes in selected combinations of following characteristics: (1) mean temperature, (2) temperature variability, (3) daily average precipitation (considering only wet days), (4) probability of wet day occurrence, (5) spatial lag-0 and lag-1day correlations of temperature and precipitation series. The synthetic series generated for each version of the CC scenario are analysed in terms the above mentioned spatial validation indices, the stress was put on effect of each of the five component of the CC scenario on individual validation indices. The results of the experiment indicate that the changes in temperature means is the main contributor to the changes in the validation obviously, except for the purely precipitation-based indices. Positive changes in the lag-0 and lag-1day correlations of both temperature and precipitation are the second most significant contributor to the changes in the validation indices.
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Uncertainties in regional climate models outputs
Holtanová, Eva ; Kalvová, Jaroslava (advisor) ; Halenka, Tomáš (referee) ; Dubrovský, Martin (referee)
Title: Uncertainties in regional climate models outputs Author: RNDr. Eva Holtanová Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Department: Dept. of Meteorology and Environment Protection Faculty of Mathematics and Physics Charles University in Prague Present doctoral thesis focuses on the analysis of uncertainties in regional climate model outputs in the area of the Czech Republic. Generally, the uncertainties in model outputs come from inaccuracies of initial and boundary conditions, further from the necessity to parameterize the small scale processes, and the structure of the model, e.g. the choice of numerical schemes or spatial resolution. In case of the simulations of future climate, another source of uncertainty arises. It is the unknown development of forcings that influence the climate system. The analysis in this work focuses on two multi-model ensembles, that come from two international European projects PRUDENCE and ENSEMBLES. The simulated 30-year mean seasonal air temperature and precipitation amounts are used, for the reference period 1961- 1990, and several future time periods. Two techniques were employed to assess the uncertainties. The first one was aimed at dividing the variance of a multi-model ensemble into contributions of regional model, driving global model and emission...
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Using growth models to evaluate field crops management practices and influence on soil processes
Hlavinka, Petr ; Trnka, Miroslav ; Balek, Jan ; Dubrovský, Martin ; Pohanková, Eva ; Wimmerová, Markéta ; Žalud, Zdeněk
The publication describes the application of growth model for evaluation of different farming methods in the cultivation of selected field crops and their influence on selected soil processes and conditions. This publication focuses on complex simulations in the soil-plant-atmosphere-farmer interaction system using the HERMES model. The ability to simulate processes in crop rotation scheme continuously and uninterruptedly (e.g. over a period of more than 100 years) gives the opportunity to assess the long-term trends in soil processes, both due to different approaches to farming and combined with selected location and soil conditions. It is possible also for selected scenarios of climate change in future. This material presents both the outputs for weather conditions without any considered climate change and conditions reflecting the shift in climatic conditions during the 21st century based on 6 selected climatic scenarios. The expected impacts on the growth and yields of the target field crops are also quantified for the selected combination of conditions.
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Evaluating drought risk for permanent grasslands under present and future climate conditions
Trnka, Miroslav ; Schaumberger, A. ; Formayer, H. ; Eitzinger, Josef ; Hlavinka, Petr ; Semerádová, Daniela ; Dubrovský, Martin ; Možný, M. ; Thaler, S. ; Žalud, Zdeněk
Over the past years, the changing climate has affected parts of Czech Republic and Austria by drought spells of the intensity and extend that was unprecedented in previous decades. These events had a significant impact on agricultural areas, especially on the grasslands. The idea behind the GIS monitoring relies on hypothesis that the effect of weather and climate conditions on the grassland production can be estimated by models that describe certain natural processes in a simplified manner and in spatialized form.
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Uncertainties in regional climate models outputs
Holtanová, Eva ; Kalvová, Jaroslava (advisor) ; Halenka, Tomáš (referee) ; Dubrovský, Martin (referee)
Title: Uncertainties in regional climate models outputs Author: RNDr. Eva Holtanová Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Department: Dept. of Meteorology and Environment Protection Faculty of Mathematics and Physics Charles University in Prague Present doctoral thesis focuses on the analysis of uncertainties in regional climate model outputs in the area of the Czech Republic. Generally, the uncertainties in model outputs come from inaccuracies of initial and boundary conditions, further from the necessity to parameterize the small scale processes, and the structure of the model, e.g. the choice of numerical schemes or spatial resolution. In case of the simulations of future climate, another source of uncertainty arises. It is the unknown development of forcings that influence the climate system. The analysis in this work focuses on two multi-model ensembles, that come from two international European projects PRUDENCE and ENSEMBLES. The simulated 30-year mean seasonal air temperature and precipitation amounts are used, for the reference period 1961- 1990, and several future time periods. Two techniques were employed to assess the uncertainties. The first one was aimed at dividing the variance of a multi-model ensemble into contributions of regional model, driving global model and emission...
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Agroclimatic analysis of perspective changes of starting production conditions for agricultural entities and related impacts to land valuation system
Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Semerádová, Daniela ; Dubrovský, Martin ; Štěpánek, Petr ; Žalud, Zdeněk
The aim of this report is to evaluate the analyses prepared within the contractual research collaboration implemented within the project number of the EEA-CZ02 1-039-2015-OV-called "Complex planning, monitoring, information and educational tools to adapt the territory to the impacts of climate change with major focus on agricultural and forest landscape management" funded by the EEA Fund 2009 - 2014 program CZ02 - Biodiversity and ecosystem services /. The study focuses on the South Moravian Region (SMR) and follows a report assessing the impact of expected climatic conditions prepared for the above-mentioned project in October 2016. Like the previous study, this part is processed based on the 5 selected global circulation models (GCMs) and for two emission scenarios and the period 2021-2040. Since a detailed description of the scenarios includes a previous report confines itself in this text only on the most important outputs relevant to SMR.
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Drivers of soil moisture trends in the Czech Republic between 1961 and 2012
Trnka, M. ; Brázdil, R. ; Balek, J. ; Semerádová, D. ; Hlavinka, P. ; Možný, M. ; Štěpánek, P. ; Dobrovolný, P. ; Zahradníček, P. ; Dubrovský, Martin ; Eitzinger, J. ; Fuchs, B. ; Svoboda, M. ; Hayes, M. ; Žalud, Z.
Soil moisture dynamics and their temporal trends in the Czech Republic are forced by various drivers. Our analysis of temporal trends indicates that shifts in drought severity between 1961 and 2012 and especially in the April, May, and June period, which displayed such results as a 50% increase in drought probability during 1961–1980 in comparison to 2001–2012. We found that increased global radiation and air temperature together with decreased relative humidity (all statistically significant at p < 0.05) led to increases in the reference evapotranspiration in all months of the growing season; this trend was particularly evident in April, May, and August, when more than 80% of the territory displayed an increased demand for soil water. These changes, in combination with the earlier end of snow cover and the earlier start of the growing season (up to 20 days in some regions), led to increased actual evapotranspiration at the start of the growing season that tended to deplete the soil moisture earlier, leaving the soil more exposed to the impacts of rainfall variability. These results support concerns related to the potentially increased severity of drought events in Central Europe. The reported trend patterns are of particular importance with respect to expected climate change, given the robustness and consistency of the trends shown and the fact that they can be aligned with the existing climate model projections. Introduction
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Balancing Assessment of Available Water Resources and Moisture Needs within Defined "Irrigation Districts”
Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Semerádová, Daniela ; Dubrovský, Martin ; Štěpánek, Petr ; Vizina, A. ; Hanel, M. ; Žalud, Z. ; Lukas, V. ; Dumbrovský, M. ; Růžek, P. ; Daňhelka, J. ; Chuchma, F. ; Novák, P. ; Novotný, I. ; Pavlík, F.
This report is processing research results done within the contractual cooperation of the Institute of Global Change Research (as a research provider) and Státní pozemkový úřad - the Czech National Land Authority (demander), which was prepared in collaboration with other research partners. The report deals with balancing assessment of available water resources and moisture needs within defined "irrigation districts” of the Czech Republic with regard to the ongoing climate change
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Drivers of soil moisture trends in the Czech Republic between 1961 and 2012
Trnka, Miroslav ; Brázdil, Rudolf ; Balek, J. ; Semerádová, Daniela ; Hlavinka, Petr ; Možný, M. ; Štěpánek, Petr ; Dobrovolný, Petr ; Zahradníček, Pavel ; Dubrovský, Martin ; Eitzinger, Josef ; Fuchs, B. ; Svoboda, M. ; Hayes, M. ; Žalud, Zdeněk
Soil moisture dynamics and their temporal trends in the Czech Republic are forced by various drivers. Our analysis of temporal trends indicates that shifts in drought severity between 1961 and 2012 and especially in the April, May, and June period, which displayed such results as a 50% increase in drought probability during 1961–1980 in comparison to 2001–2012. We found that increased global radiation and air temperature together with decreased relative humidity (all statistically significant at p < 0.05) led to increases in the reference evapotranspiration in all months of the growing season; this trend was particularly evident in April, May, and August, when more than 80% of the territory displayed an increased demand for soil water. These changes, in combination with the earlier end of snow cover and the earlier start of the growing season (up to 20 days in some regions), led to increased actual evapotranspiration at the start of the growing season that tended to deplete the soil moisture earlier, leaving the soil more exposed to the impacts of rainfall variability. These results support concerns related to the potentially increased severity of drought events in Central Europe. The reported trend patterns are of particular importance with respect to expected climate change, given the robustness and consistency of the trends shown and the fact that they can be aligned with the existing climate model projections. Introduction
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Application of growth models for local assessment of the impact of climate change on selected crops
Hlavinka, Petr ; Trnka, Miroslav ; Balek, Jan ; Dubrovský, Martin ; Pohanková, Eva ; Žalud, Zdeněk
This publication is focused on the description of specialized software named as crop growth models and its using emphasizing the application for climate change impact assessment at local scale. The ambition of this publication is to introduce brief history of the crop growth models development, its classification, actual trends of their progress and applications and last but not least, present procedure leading to the preparation of the input datasets, the initial setup, parameters calibration, validation through set of independent datasets and consequently the implementation of climate change scenarios for assessment of possible impact of future conditions on selected important field crops and set of representative sites in the Czech Republic.
Fulltext: content.csg -  PDF
Plný tet: Metodika_rustove_modely_2015 - PDF
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