PLEA2009 - 26th Conference on Passive and Low Energy Architecture, Quebec City, Canada, 22-24 June 2009 Outdoor Thermal Comfort in the Hot Arid Climate The effect of socio-economic background and cultural differences FAISAL ALJAWABRA 1 , MARIALENA NIKOLOPOULOU 1 Research Unit for the Engineering and Design of Environments, Dept. of Architecture and Civil Engineering, University of Bath, Bath, UK, fa213@bath.ac.uk ABSTRACT: Climate-sensitive open spaces within cities may benefit the three dimensions of sustainability, affecting economical, social and environmental factors. Aiming to improve microclimatic conditions in urban spaces can enable people to spend more time outdoors, with the potential to influence the social cohesion of a space and increase economic activity. The wider aim of this research is to develop better understanding of the complex relation between microclimate and human behaviour in open public spaces in hot arid climates. Case studies were carefully selected in two different parts of the world (Marrakech in North Africa and Phoenix-Arizona in North America) to represent a variety of users in similar climatic context. This enabled us to study the effect of the socio-economic and cultural diversity on thermal comfort, behaviour and use of space. Field surveys included structured interviews with a standard questionnaire and observations of the human activities, along with microclimatic monitoring, carried out during winter and summer 2008 and 2009. The analysis consists of the microclimatic influence on the thermal sensation, preference and people attendance; the effect of psychological adaptation on subjective thermal evaluation of outdoor spaces; and finally, investigation of socio-economic and socio- cultural impact on behaviour of people in outdoor space. Keywords: Thermal comfort, public spaces, hot arid climate, psychological adaptation, social differences, culture. INTRODUCTION Recently, there has been an increased interest in research focusing on thermal comfort in outdoor settings. Most of the work has been carried out in developed counties, where the majority of people spend most their time indoors [1]. Research in this area has been focusing on aspects such as the relations between thermal comfort, microclimate, behaviour and use of place and spatial variation [1, 2, 3, 4]. The psychological variables related to the thermal comfort of users in outdoor places have been the focus of a number of studies [2, 5, 6, 7]. Recently, more research has been dealing with the association between culture and climatic characteristics that influence the use of outdoor spaces [4, 8, 9], but all conducted in temperate or cold climates. This paper presents the initial results of a study conducted in outdoor spaces in the hot arid climate. The wider aim of this research is to develop better understanding of the complex relation between microclimate and human behaviour in open public spaces in hot arid climates, taking into account socio- economic background and cultural differences. Case studies were carefully selected in two different parts of the world (Marrakech in N. Africa 31°62'N 8°03'W and Phoenix-Arizona in N. America 33°26'N 112°1'W) to represent different cultural backgrounds in a similar climatic context. This enabled us to study the effect of the socio-economic and cultural diversity on thermal comfort, behaviour and use of space. The field surveys were carried out during summer and winter 2008-2009. METHODOLOGY Filed surveys were employed, where people could be studied in their "real world settings" in order to include the full complexity of conditions that subjects experience in each case study area. Data collection included environmental and human monitoring. Environmental Monitoring The environmental monitoring focused on measuring the microclimatic parameters as air temperature, wind speed, solar radiation and relative humidity and their variation, which directly affect human comfort and behaviour in the study areas. A portable set of instruments was used, to enable monitoring of the conditions different subjects were exposed to. The sensors, selected to conform to ISO 7726 [10], were fixed on the top of an adapted case, while the data logger and power supply were located inside it.