Outdoor thermal perception in different climatic regions. Initial results from Taichung (Taiwan) and Lisbon (Portugal)

Abstract

People living in different climatic regions have adapted to specific weather conditions and their tolerance to high temperatures and wind speeds is diverse. This study analyses the effect of thermal adaptations on the thermal perception of users of outdoor spaces in two different regions: Taichung (Taiwan) and Lisbon (Portugal), by means of field surveys and measurements of weather parameters. The thermal acceptable range, representing the satisfaction of people with thermal conditions, was calculated based on the Physiological Equivalent Temperature (PET) and the results obtained for each region were compared. People in Lisbon are less satisfied with higher values of PET than in Taiwan, due to the adaptation of local people to higher values of air temperature and relative humidity in Taiwan. On the contrary, people in Lisbon showed a higher tolerance to strong wind, as a result of their exposure to higher average wind speeds than those in Taiwan. The results demonstrated that people’s thermal perceptions vary with different climatic and cultural background. The influence of thermal adaptations in the use of outdoor spaces can contribute to improve the quality of these spaces, adapting them to the preferences of local users.

As populações de diversas regiões climáticas estão adaptadas a determinados estados do tempo sendo muito diversa a sua tolerância a condições extremas, como altas temperaturas e ventos fortes. Analisa-se a importância da tolerância e da adaptação na percepção térmica dos habitantes de Taichung (Taiwan) e Lisboa (Portugal), baseada na Temperatura Fisiológica Equivalente (PET). Verifica-se que os habitantes de Lisboa ficam mais insatisfeitos com altos valores de PET do que os de Taichung, habituados a temperatura e humidade mais altas. Pelo contrário, os lisboetas têm maior tolerância a ventos fortes, como resultado da sua elevada frequência. O conhecimento da influência da adaptação térmica em espaços exteriores permite aperfeiçoar a qualidade desses espaços e torná- -los mais atractivos.

Les gens qui vivent dans des régions climatiquement différentes sont adaptés à certains types de temps et ont un inégal degré de tolérance aux températures élevées et à la violence des vents. On a comparé l’influence que ces types d’adaptation ont sur les habitants de Taichung (Taiwan) et de Lisbonne (Portugal). La mesure de leur tolérance thermique est basée sur l’indice de Température Physiologique Équivalente (PET). On constate que, pour des valeurs élevées de cet indice, les habitants de Lisbonne sont moins satisfaits que les Taiwanais, mieux habitués à ces valeurs. Par contre les Lisboètes supportent mieux les vents forts, fréquents pour eux. Mieux connaitre les degrés d’adaptation des usagers aux conditions thermiques à l’air libre permettra d’améliorer les caractéristiques des espaces étudiés et de les rendre ainsi plus attractifs.