Estimating summer diurnal outdoor thermal comfort using MODIS: a spatio-temporal study in Qatar

Strategic urban planning has the potential to transform cities into climate-resilient ecosystems, thereby tackling challenges of urbanization, particularly reducing pollution and vegetation loss. One of the main consequences of urbanization is the increase in land surface temperature (LST), which exacerbates outdoor thermal discomfort—a growing concern for urban areas globally. This study examines the impact of land cover changes on outdoor thermal comfort in Qatar, a rapidly urbanizing country in the Middle East. We analyzed summer diurnal LST variations and their effect on the Discomfort Index (DI) using 23 years (decadal interval from 2000 to 2023) of MODIS (Moderate Resolution Imaging Spectroradiometer) data from Terra satellites and high-resolution Landsat imagery. Our findings reveal that the average difference between summer daytime and nighttime temperatures has decreased by 2°C. However, a detailed analysis of LST variations across different land cover types shows that urban areas experienced a decrease of 4°C in LST during the daytime from 2000 to 2023, while desert areas experienced an increase in daytime LST by 4°C. At night, the urban areas were cooler by 1°C, and the desert areas were cooler by 3°C, resulting in an increase in the diurnal range of approximately 5°C from 2000 to 2023. These regional and temporal variations underscore the vulnerability of Qatar’s arid desert ecosystems to rising summer temperatures, raising concerns about their long-term sustainability. This study emphasizes the need to implement evidence-based urban planning to improve outdoor thermal comfort and mitigate climate hazards in rapidly urbanizing arid regions.