Spatial and temporal variabilities in land surface temperatures and near-surface air temperatures in an arid to semiarid urban region: implications for urban heat island research

The significance of land surface temperature (LST) and near-surface air temperature (T AIR ) extends to various applications, including the exploration of urban heat islands. Understanding urban heat islands is crucial for comprehending the intricate interactions among urbanization, climate dynamics, and human well-being. However, many aspects of these topics remain understudied. In this study, we conducted a comprehensive analysis of LST and T AIR , covering day and night and spanning all four seasons of a full year. We used global datasets and applied non-spatial and spatial analysis techniques in the Amman-Zarqa urban region, a typical arid to semiarid environment. The study had three primary objectives: (1) Assess how different human settlement types influence the variations in LST and T AIR across space and time. (2) Examine the spatial and temporal attributes of the relationships between T AIR and LST. (3) Synthesize insights regarding the spatial and temporal characteristics of urban heat islands in arid to semiarid environments. The findings unveiled that urban centers consistently exhibit the lowest daytime LST and maximum and minimum T AIR , across all seasons when compared to other human settlement types. Nighttime LST displayed more variable patterns. Urban centers act as surface urban cool islands during the day and canopy layer urban cool islands both day and night throughout the seasons. The presence of surface urban heat or cool islands at night is barely noticeable. Daytime and nighttime LST play a significant role in explaining the variability in maximum and minimum T AIR across all seasons, with the relationships exhibiting variations ranging from positive to non-significant to negative, influenced by location and seasonal changes. During the daytime, LST consistently exceeds T AIR across all seasons, whereas this relationship displays greater variability at night. The findings of this study hold significant implications for sustainable urban planning and efforts to combat the effects of urban heat islands.