Abstract
This study investigates urban environmental variables and air quality in the hot Mediterranean climate of Tel Aviv, Israel. It does so through in-situ monitoring of the variability at the microclimate level in three different urban settings: two adjoining office towers; a bridge over an intra-urban highway and railway; and a low-mid-height residential area. All three study areas are in close proximity to each other. The role of high-rises within the urban fabric is stressed. The study was conducted during hot and humid weather conditions. It also focuses on the wind regime surrounding high buildings in that location and climate. Local conditions were compared with satellite image data (ground temperatures, pollution concentrations), as well as with data from weather and air-quality monitoring stations within a radius of 5 km. A correlation exists between high pollutant concentrations and low wind velocity and high air temperature. Urban form, building morphology (especially tall buildings) and density were shown to cause deteriorated conditions regarding pollutant concentration levels. These insights show that urban design and urban planning have a significant role in urban heat islands, air quality and climate change.
Practice relevance
Planners and architects need to ensure proper ventilation of the urban fabric by creating efficient ventilation corridors, avoiding wind barriers created by tall buildings impairing air movement downwind. Correlation is shown between high concentrations of pollutants, low wind speed and high air temperature. The configuration of urban fabric and building morphology are proven determinants of local conditions, including pollutant levels. However, when situated closely together, such buildings may create funnels increasing wind speed. Efficient ventilation becomes imperative since dispersal of pollutants and mitigation of the urban heat island are vital in curbing the morbidity and mortality rise documented in the context of rising prevalence of ever-exacerbating climatic extremes—issues to be also addressed by public health officials. Wind-protected spaces are also needed.