Effect of land use land cover changes on land surface temperature during 1984-2020: a case study of Baghdad city using landsat image

Abstract

Urban land surface temperature (LST) is dependent on many factors, including land cover, building materials, urban density, and other human activities. The current study evaluated Baghdad's LST and urban heat island (UHI) changes during 1984–2020, one of the world's hottest capital cities. The study also examined the relationship between LST and various land use and land covers (LULC). The Landsat data (TM and OLI/TIRS) data were used to retrieve normalized difference vegetation index (NDVI) and normalized difference built-up index (NDBI). Results showed increases in LST in Baghdad between 1984 and 2020 due to increased urbanization, decreased green lands, and expansion of baren areas. The highest LST is associated with residential and barren areas, ranging from 46.7 to 52.7 °C, while lowest with water bodies and orchards areas, ranging between 25 and 30.4 °C. UHI effect appeared clearly in 2020 in different parts, particularly in suburban areas around Baghdad. Higher LST was observed in less vegetated areas and vice versa. The study revealed that the average maximum temperature in Baghdad increased from 40.2 °C in 1984 to 47 °C in 2020 or about 6.8 °C during 36 years. The NDVI showed a negative correlation and NDBI a positive correlation with LST. The results improved the understanding of urban LST's relation to LULC in developing an inclusive climate resilience policy and making Baghdad more sustainable to face the consequences of climate change.