The thermal walk investigates the influence of urban design on the thermal experience of pedestrians moving through a certain urban area. Thermal walks are often used by scientists to understand how residents experience heat in urban environments. However, thermal walks can also be beneficial to urban professionals working at local governments that need to adapt urban areas to rising temperatures. Thermal walks can answer their questions such as: How hot is a shopping street, a residential area, a specific walking route through the city or a station area? Which adjustments are needed to create cool spaces? Which factors determine whether the outdoor space is hot or cool and which of these factors can be included in a heat-resilient design? A thermal walk reveals and lets participants experience which urban designs are hottest, coolest or most pleasant, and which factors play a role. Therefore, thermal walks can help urban professionals by:• Mapping the heat resilience of a specific area and understanding which adjustments can help to create cooler areas; and• Teaching them the phenomenon of urban heat and the factors that lead to a heat resilient design. On the 18th of June 2019, during the ‘We make the city’ festival, we used the thermal walk to investigate the heat resilience of the walking route on a former historic naval base in the city of Amsterdam, the Marineterrein. In addition, the thermal walk was accompanied by mini-lectures in order to teach the participants about the phenomenon of urban heat.
MULTIFILE
Thermal comfort is determined by the combined effect of the six thermal comfort parameters: temperature, air moisture content, thermal radiation, air relative velocity, personal activity and clothing level as formulated by Fanger through his double heat balance equations. In conventional air conditioning systems, air temperature is the parameter that is normally controlled whilst others are assumed to have values within the specified ranges at the design stage. In Fanger’s double heat balance equation, thermal radiation factor appears as the mean radiant temperature (MRT), however, its impact on thermal comfort is often ignored. This paper discusses the impacts of the thermal radiation field which takes the forms of mean radiant temperature and radiation asymmetry on thermal comfort, building energy consumption and air-conditioning control. Several conditions and applications in which the effects of mean radiant temperature and radiation asymmetry cannot be ignored are discussed. Several misinterpretations that arise from the formula relating mean radiant temperature and the operative temperature are highlighted, coupled with a discussion on the lack of reliable and affordable devices that measure this parameter. The usefulness of the concept of the operative temperature as a measure of combined effect of mean radiant and air temperatures on occupant’s thermal comfort is critically questioned, especially in relation to the control strategy based on this derived parameter. Examples of systems which deliver comfort using thermal radiation are presented. Finally, the paper presents various options that need to be considered in the efforts to mitigate the impacts of the thermal radiant field on the occupants’ thermal comfort and building energy consumption.
Stormwater flooding and thermal stresses of citizens are two important phenomena for most of the dense urban area. Due to the climate change, these two phenomena will occur more frequently and cause serious problems. Therefore, the sectors for public health and disaster management should be able to assess the vulnerability to stormwater flooding and thermal stress. To achieve this goal, two cities in different climate regions and with different urban context have been selected as the pilot areas, i.eY., Tainan, Taiwan and Groningen, Netherlands. Stormwater flooding and thermal stress maps will be produced for both cities for further comparison. The flooding map indicates vulnerable low lying areas, where the thermal stress map indicates high Physiological Equivalent Temperature (PET) values (thermal comfort) in open areas without shading. The combined map indicates the problem areas of flooding and thermal stress and can be used by urban planners and other stakeholders to improve the living environment.
