University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Sandro Oswald
(2021):
MICROCLIMATIC MODELLING AND ITS APPLICATION TO ENERGY BALANCE CHANGES IN URBAN ENVIRONMENTS.
Doctoral Thesis - Institut für Meteorologie und Klimatologie,
BOKU-Universität für Bodenkultur,
pp 125.
UB BOKU
obvsg
FullText
- Abstract:
- As part of this doctoral thesis, potential improvements to existing, microscale climate models were implemented and a comprehensive climate study was carried out for the city of Klagenfurt, Austria. Thereby, the focus was on the effectiveness and the correct realization of various climate adaptation measures. More people live in concentrated building complexes and the fraction of sealed surfaces has also reached enormous proportions in Austria. In combination with lower upward long-wave radiation at night, all of these circumstances lead to the so-called urban heat island effect. This effect is most pronounced shortly before sunrise. However, such tropical nights (minimum air temperature over 20 °C) are also triggered by urban heat loads during the day, i.e. the lower the daily maximum air temperature, the easier the night-time cooling is. People with jobs outdoors and vulnerable groups (elderly people) are particularly affected by the daily heat. The aim of this work is therefore to find a comprehensive and sustainable way to reduce extreme air temperatures in summer and thus mitigate thermal stress on people. In the first case study of this work, parts from an established energy balance model were used and implemented in an open-source radiation model. By increasing the model-based ground albedo in a street canyon, it was not only possible to reduce the air temperature but also to increase the energy yield of a simulated photovoltaic facade. With regard to the urban heat island effect, similar measures were applied on a large scale in the second case study and were evaluated for the city of Klagenfurt, Austria. The results were analyzed in relation to climate indices such as the average number of hot days (maximum temperature over 30 °C) per year. Through further adaptation measures such as bright and/or planted roofs, it was possible to show that the number of hot days is kept at the current level until the middle of the 21st century. However, the measures are only of limited aid against further increases in air temperature until the end of the century. It is therefore of particular importance that the reduction of CO2 emissions should continue to be the top priority.
- Betreuer: Weihs Philipp
- 1. Berater: Mursch-Radlgruber Erich
- 2. Berater: Rieder Harald