Analysis of the environmental thermal comfort conditions in public squares in the semiarid region of northeastern Brazil

This study observed the thermal sensation perceptions of users in two public squares in the semiarid region of Paraíba state, northeastern Brazil. Two cities with contrasting microclimates were selected for this study: Teixeira and Patos, which present different climatic conditions despite their geographic proximity. The main topics addressed in this study are users’ perceptions and the climatic variables that influence their comfort level in central city public squares. In this study, field measurements were performed using a Davis meteorological station, and surveys were conducted in January (a dry month) and June (a wet month) in 2016. The users of the open spaces (squares) with trees were sampled by interviews lasting approximately 5 min. Statistical analyses of the correlation between the thermal perceptions and climatological station data at the time the answers were given were based on the real sensation vote index. The city of Patos presented an Effective Temperature Index Resulting from the Wind Effect (ETv) that ranged from partially comfortable to uncomfortable, with a thermal sensation of 27–28 °C in the hours between 12:00 and 14:00. In Teixeira, the level of thermal discomfort variation was constant (i.e., comfortable) for the dry month and ranged from comfortable to partially comfortable during the rainy month. The confidence interval of Patos was 26–35 °C air temperature, 20–71% relative humidity and up to 1.5 m/s wind speed; the corresponding values for Teixeira were 18–30 °C, 40–68% and up to 3.6 m/s. The results show the level of differentiation between the two months of the year for the two cities and reveal the perceptions of people in the two cities. In January, the population prefers a colder thermal environment, which indicates the necessity of maintaining shading and ventilation.