Declining thermal walkability in the Arabian Peninsula: a thermal-climate analysis with walking implications

Walking benefits both physical and mental health. Arabian Peninsula, as one of the regions with highest physical inactivity rates, faces significant barriers to outdoor walking due to the extreme hot climate. This study defined thermal walkability as whether thermal conditions support outdoor walking based on a thermal index, modified Physiologically Equivalent Temperature, and investigated its spatial and temporal (both seasonal and diurnal) distribution and long-term trends across the Arabian Peninsula over the period 1986–2024. The results showed a pronounced seasonal contrast: October–April features widespread thermally walkable conditions for most non-sleeping hours, with little decadal change; while summer and transitional months experienced poor thermal walkability, with thermally walkable hours mainly around sunrise and after sunset, and the probability of thermal walkability during these periods was declining significantly. The meteorological drivers of thermally unwalkable conditions for four major cities were identified based on the results of logistic regression and random forest models. Air temperature and solar radiation turned out to be the primary determinants while wind velocity and vapour pressure have weak effects across hot-arid to hot-humid climates. These findings highlight the necessity for region- and time-specific mitigation and adaptation strategies against the reduced thermal walkability and offer valuable references for policymakers to create supportive environments for outdoor walking.