Are urban water bodies really cooling?

Small urban water bodies, like ponds or canals, are often assumed to cool their surroundings during hot periods, when water bodies remain cooler than air during daytime. However, during the night they may be warmer. Sufficient fetch is required for thermal effects to reach a height of 1–2 m, relevant for humans. In the ‘Really cooling water bodies in cities’ (REALCOOL) project thermal effects of typical Dutch urban water bodies were explored, using ENVI-met 4.1.3. This model version enables users to specify intensity of turbulent mixing and light absorption of the water, offering improved water temperature simulations. Local thermal effects near individual water bodies were assessed as differences in air temperature and Physiological Equivalent Temperature (PET). The simulations suggest that local thermal effects of small water bodies can be considered negligible in design practice. Afternoon air temperatures in surrounding spaces were reduced by typically 0.2 °C and the maximum cooling effect was 0.6 °C. Typical PET reduction was 0.6 °C, with a maximum of 1.9 °C. Night-time warming effects are even smaller. However, the immediate surroundings of small water bodies can become cooler by means of shading from trees, fountains or water mists, and natural ventilation. Such interventions induce favorable changes in daytime PET.</p

Engrained experience—a comparison of microclimate perception schemata and microclimate measurements in Dutch urban squares

Acceptance of public spaces is often guided by perceptual schemata. Such schemata also seem to play a role in thermal comfort and microclimate experience. For climate-responsive design with a focus on thermal comfort it is important to acquire knowledge about these schemata. For this purpose, perceived and “real” microclimate situations were compared for three Dutch urban squares. People were asked about their long-term microclimate perceptions, which resulted in “cognitive microclimate maps”. These were compared with mapped microclimate data from measurements representing the common microclimate when people stay outdoors. The comparison revealed some unexpected low matches; people clearly overestimated the influence of the wind. Therefore, a second assumption was developed: that it is the more salient wind situations that become engrained in people’s memory. A comparison using measurement data from windy days shows better matches. This suggests that these more salient situations play a role in the microclimate schemata that people develop about urban places. The consequences from this study for urban design are twofold. Firstly, urban design should address not only the “real” problems, but, more prominently, the “perceived” problems. Secondly, microclimate simulations addressing thermal comfort issues in urban spaces should focus on these perceived, salient situations

Technology and Society in Equilibrium:

This sector portrait of the design engineering sciences describes the common denominator of the various design disciplines in the Netherlands. In a future sector plan, the above investment areas will be further explored and purposefully developed. The implementation of technological innovations aligned to societal issues encompasses a design challenge. This increasingly demands science-based design methodologies. The broad Dutch design landscape can fulfil the role of connector well in this regard. In order to optimally strengthen this bridging function, three areas for further investment have been identified: Research More research and research funding are needed to meet the design challenges posed by Dutch societal missions, as well as for the further development of Key Enabling Methodologies (KEMs) as the basis for effective design. Educational Capacity Expanded teaching capacity and further development of design-driven didactics are needed to meet the growing demand for designers, This demand stems from the emerging need for design approaches in new research programmes within Horizon Europe and the Dutch Research Council (NWO). Access to Technology Continuous access to the rapidly evolving technological disciplines must be guaranteed for professionals who can both understand the technology and meet the investigative design challenge

Technologie en Maatschappij in Balans:

Dit sectorbeeld van de ontwerpende ingenieurswetenschappen beschrijft de grote gemeenschappelijke deler van de verschillende ontwerpdisciplines in Nederland. In aanloop naar het schrijven van dit sectorbeeld hebben we gezamenlijk bepaald waar onze sterkte ligt, en waar we concreet kunnen bijdragen aan het oplossen van maatschappelijke knelpunten. Implementatie van technologische innovaties in aansluiting op maatschappelijke uitdagingen omvat een ontwerpopgave. Dit vereist in toenemende mate wetenschappelijk onderbouwde ontwerpmethodieken. Het brede Nederlandse ontwerplandschap kan hierbij de rol van verbinder goed vervullen. Teneinde deze brugfunctie optimaal te versterken worden drie gebieden voor verdere investeringen gezien: Onderzoek Er is meer onderzoek en onderzoeksfinanciering nodig voor het volbrengen van ontwerpuitdagingen die in de Nederlandse maatschappelijke missies worden gesteld, evenals voor de verdere ontwikkeling van Key Enabling Methodologies als basis voor effectief ontwerp. Onderwijscapaciteit Er is een ruimere onderwijscapaciteit en verdere ontwikkeling van ontwerp gestuurde didactiek nodig om te kunnen voldoen aan de groeiende vraag naar ontwerpers, een vraag die voortkomt uit de opkomende behoefte aan ontwerpaanpakken in nieuwe onderzoeksprogramma’s binnen Horizon Europe en NWO. Toegang tot technologie Er moet voortdurend toegang gegarandeerd zijn tot de zich snel ontwikkelende technologische disciplines voor professionals die zowel de technologie doorgronden als de onderzoekende ontwerpuitdaging aankunnen. Dit sectorbeeld van de ontwerpende ingenieurswetenschappen beschrijft de grote gemeenschappelijke deler van de verschillende ontwerpdisciplines in Nederland. In een toekomstig sectorplan zullen bovenstaande inversteringsgebieden verder en doelgericht worden uitgewerkt

Historical vegetation for microclimate amelioration : a case study for The Netherlands

Current solutions for climate amelioration require excessive amounts of energy, such as air conditioners and patio heaters. Yet, historical energy-passive climate-responsive design solutions exist that have a potential for outdoor microclimate control. Regarding these solutions, there was no overview of historical vegetation for microclimate amelioration in oceanic climate zones. We therefore explored historical vegetation types for microclimate amelioration in the Netherlands, for the example of oceanic climate zones. We identified six vegetation types: espaliered trees, tree lanes, berceaux, shelterbelts, green walls and umbrella trees. For each type we described their historical microclimatic function(s) and discussed their quantitative microclimatic effects based on available literature. Whilst tree lanes and green walls are currently applied to ameliorate urban microclimate, this seemed not to be the case for umbrella trees, espaliered trees, shelterbelts and berceaux. We therefore recommend urban designers to also consider these other historical vegetation types for passive outdoor microclimate amelioration

Post-positivist microclimatic urban design research : A review

'Research Through Designing' (RTD) is a research method that is based on the active employment of designing in the research process. Often, RTD is necessary to generate knowledge that is relevant for design such as design guidelines or prototypes. A broad range of RTD methods can be used to produce such results: post-positivist, constructivist, participatory and pragmatist approaches. The aim of this paper is to elucidate the post-positivist RTD methods through the discussion of examples. The examples represent microclimate responsive design research and were derived from an extensive literature review. The typical issues to be dealt with in such studies are discussed: complexity, scale, testing methods and their mutual relations. A distinction is made between RTD methods and other design research for microclimatic improvement. Three studies occurred to be RTD in the literal sense and they provide a methodological model for further research to generate evidence that supports urban microclimate responsive design

Exploring outdoor thermal perception—a revised model

<p>This paper aims at extending earlier models of outdoor thermal perception by fusing new knowledge from recent literature and deriving perspectives for future research and methods from the new model. Previous models focused on physical and physiological aspects. Only recently, the psychological aspects of thermal perception received more attention, such as spatial perception. Furthermore, in recent literature on thermal perception, two time scales have been described: the short-term and the long-term thermal perception. Based on this new literature, we develop a conceptual, more comprehensive model that takes these factors into account as well. It hypothesizes how thermal sensation and psychological processes interact on the two time scales. However, to be able to describe relationships between psychological aspects of thermal perception more precisely, more research is required on the following issues: (1) influence of momentary personal references and preferences (e.g., mood), (2) influence of long-term personal references and preferences (e.g., cultural aspects, habituation), and (3) influence of the perception of the spatial environment on thermal perception. Moreover, the relation between momentary and long-term thermal perception has not been studied yet. We conclude this paper with an outlook on possible methods to study these factors.</p

Exploring outdoor thermal perception—a revised model

This paper aims at extending earlier models of outdoor thermal perception by fusing new knowledge from recent literature and deriving perspectives for future research and methods from the new model. Previous models focused on physical and physiological aspects. Only recently, the psychological aspects of thermal perception received more attention, such as spatial perception. Furthermore, in recent literature on thermal perception, two time scales have been described: the short-term and the long-term thermal perception. Based on this new literature, we develop a conceptual, more comprehensive model that takes these factors into account as well. It hypothesizes how thermal sensation and psychological processes interact on the two time scales. However, to be able to describe relationships between psychological aspects of thermal perception more precisely, more research is required on the following issues: (1) influence of momentary personal references and preferences (e.g., mood), (2) influence of long-term personal references and preferences (e.g., cultural aspects, habituation), and (3) influence of the perception of the spatial environment on thermal perception. Moreover, the relation between momentary and long-term thermal perception has not been studied yet. We conclude this paper with an outlook on possible methods to study these factors.</p