Analyzing the urban heat Island: Comprehensive methodology for data gathering and optimal design of mobile transects

Abstract

The Urban Heat Island phenomenon is an increasingly important global issue. Understanding the physical characteristics of cities is critical, which is why many studies based on mobile measurements are currently being developed. However, it is highly challenging to compare them due to the various methods that are employed. Therefore, the present work aims to propose an easily replicable methodology for achieving accurate UHI assessments in potentially any city of the world. This is done by finding a representative mobile transect through experimental data, as opposed to previous studies which select routes with a variety of land covers, with the consequent risk of overlooking the truly representative areas. The main urban indicators are also estimated by using public information, including the anthropogenic heat.

The methodology was tested in the historic city center of Seville (Spain). The designed mobile transect was repeatedly conducted in July 2019, recording a maximum UHI intensity of 3.1 °C at 22:00 h. A fixed temperature sensor showed that the maximum UHI intensity may be found around 06:00 h, reaching even more than 7 °C. The proposed methodology could be very useful for researchers and policy makers, allowing to direct mitigation strategies and economic investments to areas of particular vulnerability.