Thermal–Mobility Nexus in Riyadh: Integrating TOD and Climate Adaptation for Hot-Climate Urban Futures

Abstract

Extreme heat and car-oriented urban development have created a reinforcing mobility challenge in Riyadh, where uncomfortable pedestrian conditions discourage walking and public transport use and strengthen dependence on private vehicles. This study examines how urban design and mobility strategies can be integrated to reduce car dependency and improve resilience to extreme heat. It develops the Thermal–Mobility Nexus, a framework that positions thermal comfort as a fundamental condition for accessibility rather than an optional urban design feature.

The research adopts a qualitative comparative case-study approach combining documentary analysis, spatial assessment and regional benchmarking. Three major Riyadh policy instruments were analysed alongside an audit of the 800-metre catchment surrounding King Salman Park Metro Station, supported by satellite imagery and 47 field photographs. Dubai and Doha were examined as comparative hot-climate cases. The analysis applied indicators related to shade coverage, corridor continuity, Mean Radiant Temperature and the Universal Thermal Climate Index.

The findings reveal a substantial disconnect between Riyadh’s transport investment and the thermal conditions of first- and last-mile pedestrian routes. Shade provision is fragmented, pedestrian corridors remain highly exposed, and mobility and greening policies are implemented through separate institutional structures. The study therefore recommends a binding Thermal Performance Code for station catchments, a cross-agency Thermal–Mobility Coordination Unit, and a corridor activation programme prioritising shaded, mixed-use routes for transit-dependent and heat-vulnerable populations. The proposed framework demonstrates how integrated governance, climate-responsive urban design and measurable thermal standards can improve public transport accessibility and support more equitable, walkable and climate-resilient urban development in Riyadh and other hot-climate cities.

Keywords: Thermal–Mobility Nexus; Transit-Oriented Development; extreme heat; thermal comfort; car dependency; Riyadh; climate adaptation; walkability.