Climatology of Surface Urban Heat Island of Ahwaz Metropolis

Human activities control the microclimate of the city and one of the most important effects of it is the urban heat island phenomenon. The heat island affects the quality of urban life, including energy consumption, air and water quality, as well as human health. Ahwaz, on the other hand, is one of the hottest cities in Iran. Therefore, the study of the heat island of Ahwaz and the knowledge of urban microclimate is worthy of consideration.e. For this purpose, in this study, the heat island of Ahwaz metropolitan area was investigated in terms of temporal and spatial variations by using the data of temporal temperature data of the MODIS-Terra and MODIS-Aqua observations from 2002 to 2017. The intensity of the heat island was measured based on the background climate. To this end, after the city boundary was determined by the latest Google Earth imagery. Then, a range, of the size of the city, was determined around the city and was called the non-urban. The temperature that was most common among all the non-urban cells was considered as the temperature of the non-urban. The temperature difference of all the non-urban cells of the city was obtained from the non-urban temperature. The average temperature difference of all cells from the temperature of non-urban was obtained and called the average intensity of the heat/cold island. The results showed that Ahwaz, during the day has a cold island (-2 degrees Centigrade), and at night was a heat island (2.2 degrees Centigrade). Due to the fact that the Karun river passes through the city, heat island is divided into two parts. The eastern and western parts of the city have more procedural temperatures than the city average. Also, the core of the nightly heat island and the weak parts of the daily cold island are in line with the industrial zone of Ahwaz.