Evaluation of spectral indices and extraction of constructed and non-constructed urban features and its comparison with ground surface temperature using Landsat 7 and 8 satellite images (Study area, Tehran)

Surface temperature is one of the important indicators in the study of models of energy balance at the surface and interactions between the earth and the atmosphere on a regional and global scale. Today, satellite imagery in thermal infrared and red wavelengths is a good source of information for water and land surface thermal mapping due to its extensive coverage. Today, the phenomenon of thermal islands in cities causes many human and financial losses to citizens. One of the problems in cities is that to study and control this phenomenon, you can use appropriate satellite images and identify and manage the infected parts of the city. Therefore, the purpose of this study is to prepare the changes made in urban constructions and the uncontrolled increase of buildings and their relationship with the ground surface temperature using the data of ETM and OLI sensors of Landsat satellite in 2002 and 2019 for Tehran. In this study, the Gram_Schmidet method, which was developed to combine these images, was used. And data for 2002 and 2019, all captured in winter, were prepared, analyzed and evaluated. Correlation coefficient and kappa coefficient indices have been used to verify the method and classification accuracy. The results show; The VbSWIR_BI and IBI indices have the highest accuracy compared to other indices while the results of VbSWIR_BI index show the temporal and spatial changes of Tehran in an acceptable result. Also, according to the results obtained through the surface temperature, with the increase in construction, the increase in temperature in Tehran has been extended to the northern and central regions of the city.