The complex role of trees as the most popular heat wave mitigation measure in Czech cities

0586346 - ÚI 2025 PL eng A - Abstract
Geletič, Jan - Krč, Pavel - Resler, Jaroslav - Bureš, Martin - Řezníček, Hynek - Belda, Michal
The complex role of trees as the most popular heat wave mitigation measure in Czech cities.
International conference Earth as a Human-Environmental System: Challenges and Dynamics. Book of abstracts. Kraków: Jagiellonian University in Kraków, 2024. s. 64-64.
[EarthHES2024: International Conference Earth as a Human-Environmental System: Challenges and Dynamics. 06.05.2024-08.05.2024, Kraków]
Grant - others:AV ČR(CZ) StrategieAV21/23
Program: StrategieAV
Institutional support: RVO:67985807
OECD category: Meteorology and atmospheric sciences
https://geo.uj.edu.pl/documents/141809825/155010702/ksi%C4%85%C5%BCka+abstrakt%C3%B3w+175+lat+IGiGP+UJ.pdf https://geo.uj.edu.pl/documents/141809825/155010702/Conference_programme.pdf

Generally, trees are widely considered the most effective heat wave mitigation measure in cities. Most of their positive effects are well described and analyzed in detail. Despite that, their effect on their surroundings is not homogeneous. Trees in urban canyons significantly affect the energy balance of horizontal and vertical surfaces. Moreover, they decrease wind velocity and block night-time radiative cooling of horizontal surfaces. The role of trees in the urban canyon is more complex – they can decrease surface temperature (ST) or mean radiant temperature (MRT) by about tens °C, same as related biometeorological indices, e.g. universal thermal climate index (UTCI) or physiological equivalent temperature (PET); maximum decrease can be as high as 10–15 °C. All these decreases are located close to trees, with only a slight effect on their surroundings. Moreover, they strongly vary during the day. New studies based on large-eddy simulation principles proved that there are more dependencies than expected; e.g. that newly planted trees on the north sides of buildings have only a minor effect on MRT, UTCI and PET. There is also a strong dependency between UTCI reduction and building height or distance between tree and building. Finally, the effect of trees is often modeled with optimal soil moisture and health conditions mainly due to a lack of data about trees in urban environments. The modern urban planning tools supported by scientific simulations could support a ‚smart city‘ concept
Permanent Link: https://hdl.handle.net/11104/0353893