Design Tools to Assess Outdoor Thermal Comfort in Hot, Dry and Semi-arid City of Petrolina in Brazil

Mehta, Ketki; Banteli, Amalia

Abstract

Outdoor thermal comfort in hot semi-arid tropical climates of the southern hemisphere is under-researched. Predictive outdoor thermal comfort indices such as OUT_SET and ET* have been developed. Universal indices such as UTCI predict thermal comfort in any season or bioclimatic zone, whether indoors or outdoors. However, there are no verifiable field studies in hot-dry-semi-arid bioclimates to use them directly for prediction in Petrolina. Physiological Effective Temperature (PET) has been used recently in many field studies for outdoor thermal comfort, some of which are in hot-dry climates. A few scholars have recalibrated the PET vs. Fanger scale for their field study. However, these are restricted to specific studies and lack general applicability. This chapter focuses on developing design tools to assess outdoor thermal comfort for activities in hot-dry-semi-arid climates in the absence of reliable indices, adapting them for Petrolina, Brazil.

Katafygiotou and Serghides (Indoor Built Environ 24(6):746–760, 2014) have reinterpreted Olgyay’s bioclimatic chart for hot-humid climates. Olgyay’s bioclimatic chart is the starting point for this research due to its simplicity and versatility. Hot-dry climates are chosen explicitly as different from hot-humid climates as their thermal comfort requirements vary considerably, clearly shown by various studies. The methodology identifies thermal preferences and acceptable temperature ranges from the literature. Tools to define context-specific thermal comfort utilise bioclimatic evaluation, site wind, land surface temperatures and shade study tools. This method can be replicated for other sites in hot-dry semi-arid bioclimates. A ‘mismatch analysis’ methodology was used to propel the design process and arrive at proposals for a dual-activity outdoor space.

This research facilitates translating the cultural psychology of thermal comfort and physiological acclimatisation into measurable comfort parameters. It enables designing for thermal comfort in hot semi-arid regions but does not account for discomfort due to urban heat islands or the effects of drought or excess rainfall because of or despite El Niño–Al Niña cycles.

• Presentation Conference Type: Conference Paper (published)
• Conference Name: International Conference of Sustainable Ecological Engineering Design for Society (SEEDS) 2021
• Start Date: Sep 1, 2021
• Publication Date: Apr 2, 2025
• Deposit Date: Jun 7, 2025
• Publisher: Springer
• Peer Reviewed: Peer Reviewed
• Volume: 1
• Pages: 115–140
• Book Title: Sustainable Ecological Engineering Design
• ISBN: 9783031739477
• DOI: https://doi.org/10.1007/978-3-031-73947-7_8