Landsat-8 TIRS Data for Assessing Urban Heat Island Effect and Its Impact on Human Health

Heat waves are reaching our cities more frequently nowadays, leading to the urban heat island (UHI) effect. Measured by the remotely sensed land surface temperature (LST), the effect is frequently called surface UHI (SUHI). In Estonia, the SUHI has been studied little and the LST method has not being used yet in studies of Estonian cities’ microclimate. The analysis clearly reveals that the effect of UHI in Estonian settlements is larger than ever assumed. Satellite images showed that Tallinn suffers from quite strong UHI effect. Landsat-8 thermal infrared sensor image from July 25, 2014 shows that for all settlements of densely populated Harju County, the temperature is higher than that in the surroundings by 3 °C–5 °C. To evaluate potential impact to the health of vulnerable groups of residents of Tallinn city, we applied an “exposure to risk—sensitivity—impact” method to evaluate the potential impact of the UHI effect on the health of vulnerable groups of residents of Tallinn city. Our analysis showed that the parts of Tallinn severely affected by heat are mostly the areas of apartment buildings with lower real estate prices. Thus, those areas have also a higher population density and more vulnerable people live there. Produced map of UHI impact can be successfully used for spatial planning measures for adaptation to climate change.