Projects / Programmes
Preventing heat stress in urban systems under climate change
| Code |
Science |
Field |
Subfield |
| 1.08.00 |
Natural sciences and mathematics |
Control and care of the environment |
|
| 6.12.01 |
Humanities |
Geography |
Physical geography |
| Code |
Science |
Field |
| T181 |
Technological sciences |
Remote sensing |
| Code |
Science |
Field |
| 1.05 |
Natural Sciences |
Earth and related Environmental sciences |
| 5.07 |
Social Sciences |
Social and economic geography |
urban heat island, climate change, urban systems, heat stress, green areas, mitigation and adaptation startegies
Researchers (10)
Organisations (3)
Abstract
Owing to population growth, cities worldwide are expanding. Understanding densely populated urban ecosystems as well as maintaining quality of life in these environments is therefore of high importance. For historical reasons, the vast majority of Slovenian urban settlements are concentrated, which increases the so-called urban heat island (UHI) effect. In response to removal of the natural land cover in cities and the introduction of artificial materials (e.g., concrete, asphalt, tiles, metals, etc.), the radiative, thermal and moisture conditions as well as roughness and emissivity of the surface (and consequently the atmosphere above) change dramatically. As a result, alternation of surface energy fluxes occurs, with a consequent increase in the Bowen ratio (the ratio of sensible to latent heat fluxes), which, in turn, causes an increase in temperatures on and above every urban surface. While most recent studies about this urban–rural temperature anomaly focus on large metropolitan areas or mid-size cities, which require thermal remote sensing data and cloudless meteorological conditions, very few studies explore UHI properties in small cities or towns under optimal or other weather conditions. Moreover, the climate change impact on the UHI phenomenon is nevertheless purely studied. Climate change and the UHI effect interact in two important ways. First, our warming climate will increase already higher temperatures in UHI areas. Second, cooling strategies to reduce UHIs can help communities adapt to the impacts of climate change as well as lower the greenhouse gas emissions that cause climate change.
By considering these facts, the research questions to be answered in this project are the following: (a) How large is the city/town size effect on the UHI phenomenon in the Sub-Pannonian part of Slovenia?; (b) How intensive and spatially diverse are the developed UHIs and which factors are causing such patterns?; (c) How large is the cooling effect of green space in different sized cities/towns?; (d) Which species groups with specific canopy cover contribute the most to the cooling effect?; How does UHI effect plant phenology in different size cities/towns?; (e) How large is the response of vegetation (in the form of bioclimatic indicators [start of growing season, end of growing season and total growing season length, sum of active and effective temperature etc.]) as a consequence of the UHI phenomenon? (f) How will climate change influence these UHI patterns (extreme heat events and increased average temperature), and finally (g) what mitigation measures should be realized in order to coup with the foreseen treats and pressures in the forthcoming warmer second half of the century?
The proposed 2-dimensional and 3-dimensional methodological approach in this project is a step forward in urban climate studies. The high-resolution data enable a completely new look into thermal process in urban systems. However, understanding and quantifying UHI and its factors are important steps toward improving the quality of life of urbanites and achieving urban sustainability in all types of cities across the globe. Thus, the results of this project carries an important added value, since the proposed solutions are transferable to other cities in mid-latitudes with comparable regional climate conditions. Precisely relevant to such a perspective are ‘’state of the art’’ geospatial models that can sufficiently predict UHI intensity and morphology, not only in optimal weather conditions but in others as well, of crucial importance for urban and environmental planners, who are obligated to prepare adequate mitigation measures and adaptive strategies.
Significance for science
There are no existing studies in Slovenia, that consider climate change issues in combination with the UHI effect at different scales. There are no concrete strategies to prevent the negative impacts of this increasing phenomenon in Slovenia and existing mitigations measures are rarely implemented in practice. Unfortunately, more examples of urban green space reduction or even complete removal can be listed than realized examples of good practices. Moreover, despite the fact that 60% of the country if covered with forest, are urban heat stress indices nevertheless almost everywhere significantly positive. This information leads to the conclusion that our urban areas are lacking of appropriate green space which triggers the cooling effect. The results of this project are therefore urgently needed to raise awareness among citizens and provide science-based information to prevent the expected negative impacts of climate change in the urban environment in years to come. Secondly, the developed city/town-specific UHI models will reveal some general patterns, which can be than transferred to other cities/towns exhibiting comparable climatic traits. Thus, the findings in this project are definitely of regional, or in some perspectives, even global importance. Further on, if humanity wants to reduce the record-breaking CO2 emissions (410 ppm, 16.11.2018; https://climate.nasa.gov/vital-signs/carbon-dioxide/) and somehow mitigate human-induced climate change, many multidimensional steps towards prevention and adaptations should be made. Starting with cooling strategies to reduce heat islands in densely populated areas is definitely a ‘’bullseye’’ since countermeasures will be implement exactly at the origin of most greenhouse gas emissions. Finally, the provided results will have a very high value for urban and environmental planners who are obligated to prepare adequate mitigation measures and adaptive strategies at the right place and in an opportune moment.
Significance for the country
There are no existing studies in Slovenia, that consider climate change issues in combination with the UHI effect at different scales. There are no concrete strategies to prevent the negative impacts of this increasing phenomenon in Slovenia and existing mitigations measures are rarely implemented in practice. Unfortunately, more examples of urban green space reduction or even complete removal can be listed than realized examples of good practices. Moreover, despite the fact that 60% of the country if covered with forest, are urban heat stress indices nevertheless almost everywhere significantly positive. This information leads to the conclusion that our urban areas are lacking of appropriate green space which triggers the cooling effect. The results of this project are therefore urgently needed to raise awareness among citizens and provide science-based information to prevent the expected negative impacts of climate change in the urban environment in years to come. Secondly, the developed city/town-specific UHI models will reveal some general patterns, which can be than transferred to other cities/towns exhibiting comparable climatic traits. Thus, the findings in this project are definitely of regional, or in some perspectives, even global importance. Further on, if humanity wants to reduce the record-breaking CO2 emissions (410 ppm, 16.11.2018; https://climate.nasa.gov/vital-signs/carbon-dioxide/) and somehow mitigate human-induced climate change, many multidimensional steps towards prevention and adaptations should be made. Starting with cooling strategies to reduce heat islands in densely populated areas is definitely a ‘’bullseye’’ since countermeasures will be implement exactly at the origin of most greenhouse gas emissions. Finally, the provided results will have a very high value for urban and environmental planners who are obligated to prepare adequate mitigation measures and adaptive strategies at the right place and in an opportune moment.
