A comprehensive review of thermal comfort studies in urban open spaces

Thermal Comfort in Urban Spaces

“…For example, in Taiwan, the thermal comfort zone for PET neutral is 21.3-28.5 °C (Lin 2009), while in Belo Horizonte it is 19-27 °C (Hirashima et al 2016) with the wide zones also encompassing the seasonal variation. In subarctic climate zones, we see a dramatic reduction in the comfort zone, albeit still quite wide, with people adapting at the 10-17 °C PET comfort zone in Umeå (Yang et al 2017), with a similar lower threshold of 10.2 °C PET for the winter city of Harbin (Lai et al 2020).…”

“…Following the seminal studies of Nikolopoulou in Cambridge (Nikolopoulou et al 2001;Nikolopoulou and Steemers 2003) and the subsequent large-scale RUROS project, still the largest single study and database available for meta-analysis with nearly 10,000 interviews (CRES 2004), investigating comfort studies in Greece, Italy, Switzerland, Germany and the UK (Nikolopoulou and Lykoudis 2007), various reviews (Nikolopoulou 2012;Mahgoub and Hamza 2019;Lai et al 2020) have enabled a systematic and comprehensive understanding of outdoor thermal comfort.…”

“…For example, with the use of Likert scales, there is a range of comfort, thermal sensation or satisfaction and preference scales. Even for thermal sensation scales, these vary from the standard ASHRAE 7-point scale developed for indoors (ISO 7730 2005 andASHRAE 2013, which is the most extensively used in hundreds of surveys across the world; see Lai et al 2020) to simplified 5-point scales (e.g. Nikolopoulou et al 2001;Nikolopoulou and Lykoudis 2006;Fontes et al 2008) or even 9-point scales (e.g.…”

“…One of the main issues highlighted is the discrepancy between theoretical thermoregulatory models and actual conditions of thermal comfort with environmental parameters accounting for only about half of the variation in thermal sensation (Nikolopoulou et al 2001;Nikolopoulou 2004;Eliasson et al 2007;Nikolopoulou 2012;Lai et al 2020). Conducting outdoor comfort surveys in different parts of the world enabled the development of empirical comfort models as a function of the different microclimatic conditions experienced, the weighting of which varied depending on the climatic context.…”

“…changing of clothing in different conditions. For example, research has highlighted the seasonal variation of clothing (Aljawabra andNikolopoulou 2010, 2018;de Vet 2017;Leng et al 2020), and as a direct function of temperature (Nikolopoulou et al 2001;Nikolopoulou 2004;Nikolopoulou and Lykoudis 2006;Yahia and Johansson 2013;Aljawabra and Nikolopoulou 2018;Lai et al 2020).…”