Links between temperature and precipitation in Central Europe

Bc. Michaela Porazíková

Diplomová práce

Abstract:

In recent years, Central Europe has experienced frequent periods of significantly above-average temperatures and below-average precipitation, especially in spring and summer. This combination poses serious problems, including impacts on agriculture and water resources. Therefore, the thesis examines the following interrelationships between temperature and precipitation in the summer months (June-August ) over the period 1950-2024 in Central Europe. The aim of the thesis was to analyse the relationships between temperature and precipitation characteristics in the observed data (post-1950 period), including their relation to other meteorological factors. The work also assesses how extreme events have changed over time and how their spatial distribution is related to the occurrence of droughts and floods. The study area is defined as the space between approximately 48-52°N and 10-20°E, which includes the Czech Republic, part of Slovakia, Poland, Austria and Germany. The analysis was performed using daily temperature and precipitation data from the E-OBS dataset (version 28.0e) and further processed in RStudio (version 2023.03.0). For all 75 summers, the average summer temperature was first calculated, according to which the summers were then divided into three groups (25 cool summers, 25 mild summers and 25 hot summers). Descriptive statistics and correlation analysis were performed for each group. Extreme events were identified using 10th and 90th percentile thresholds and compound events were evaluated using four predefined scenarios: cold + wet, cold + dry, hot + wet and hot + dry. To ensure regional relevance, only spatially clustered extreme events defined by at least 25% of the nodal points meeting the threshold conditions were retained. Kriging interpolation was used to visualize spatial patterns. The results show a marked increase in extremely hot days and a sharp decrease in extremely cold days, with hot summer seasons manifesting increased precipitation and, since 2000, a higher frequency of high precipitation days. In contrast, the composite event types behaved differently, with cold + wet and hot + wet events occurring most frequently, while hot + dry events were spatially more inconsistent and related to major drought years such as 2003, 2015 and 2018. The observed dynamics thus provide useful information on the relationship between temperature and precipitation in Central Europe and offer a clear basis for further application in regional climate extremes assessments.

Keywords

air temperature, precipitation, drought, floods, Central Europe

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 3. 4. 2025

Obhajoba závěrečné práce

• Obhajoba proběhla 19. 5. 2025
• Vedoucí: doc. RNDr. Jan Kyselý, Ph.D.
• Oponent: Marta Martínková, Ph.D.

Česká zemědělská univerzita v Praze

Fakulta životního prostředí

Magisterský studijní program:
Environmental Modelling