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.

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.