Achieving sustainable development goals through the study of urban heat island changes and its effective factors using spatio‐temporal techniques: The case study (Tehran city)

The present study is aimed at investigating the spatio‐temporal structure of land surface temperature (LST) and its interrelationship with physical and biophysical land surface properties, such as land use, vegetation, the indicators of climate changes and air pollution, and the density of buildings in Tehran city of Iran, using Landsat 5, 7 and 8 thermal bands of satellite images in cold and hot seasons during the 1984–2020 period. The results indicate that the mean LST of Tehran city has gradually increased over time. LST results in a hot season, such as May showed that the changes in 1990 were between 6 and 44°C, in 2000, between 20 and 44°C, in 2013 between 14 and 42°C and in 2020 the changes were between 15 and 51°C. Also, the formation of hot spots in the west and south demonstrated the direct connection pattern of the distribution of space. According to the results, a strong negative LST‐NDVI and positive LST‐NDBI correlation are observed throughout the period. In addition, as to the other indices, the results indicate a positive correlation among LST, and air pollution indicators (NO2, SO2, CO, CO2, PM2.5, and PM10 ppm), a negative correlation with precipitation and a positive correlation with temperature in climatic indices and negative LST‐ Humidity, NDWI, and NDMI. These show the regions where water can weaken the UHI effect in the city. LST also has a positive correlation with buildings density and population centers, as well as industries concentrated in the western regions of Tehran that are subjected to rising LST. The mixed urban landscape of the city is closely related to the changes of the LST and the indicators, including NDVI, different land covers, and urban industrial and commercial activities. Finally, the regional vulnerability of Tehran as a metropolis was determined by using geographic information systems and spatio‐temporal methods. Based upon the results, the western regions of Tehran had more urban vulnerabilities in terms of thermal phenomena and the northern regions remain with the least vulnerability.