Investigating the effect of land use changes on land surface temperature in cold and semi-arid areas (Case study: Central Zone of Sanandaj City)

Nowadays, different societies are facing increasing population and extensive urbanization. Land use changes is one of the phenomena that is very important in the world and has significantly impact on the environment. The purpose of this research is investigating the effect of land use change on land surface temperature in the central zone of Sanandaj city. Using supervised classification method, maximum likelihood algorithm, the land use map was classified into five categories agriculture, bare, urban, vegetation, and water. The land surface temperature examined using Sebal algorithm in a period of 19 years. The obtained results from land use analysis in the study area revealed that urban, agriculture, vegetation and water areas show an increasing trend but bare lands show a decreasing trend from 2000 to 2019. Minimum land surface temperature arrived to 6.15 ºC and 5.26 ºC in 2000 and 2019, respectively. Also, maximum temperature increased from 49.22 ºC to 51.39 ºC in this 19 years period. The highest surface temperature in both mentioned years were obtained in bare lands. Vegetation and water areas have the lowest surface temperature in this period. Unlike Mediterranean and tropical cities which experience the urban heat island, Sanandaj city, with cold and semi-arid climate, experienced the urban cool island. Urban cool island is due to the surrounding urban areas with bare lands with high surface temperature.