Relationship between land surface temperature and air quality in urban and suburban areas: Dynamic changes and interaction effects

Urbanization process contributes to localised urban climate changes, specifically the land surface temperature (LST) and air quality. The urban heat island (UHI) effect and air pollution have become widespread environmental problems in urban areas. Although previous studies have identified the interaction between the UHI and air pollution, its impact on air pollution has not been adequately investigated. This study investigates the dynamics between Surface Urban Heat Island (SUHI) effects and air pollution within the Beijing-Tianjin-Hebei Urban Agglomeration (BTHUA) during 2016-2022. Findings reveal a consistent decline in both SUHI and air pollution levels, with a marked increase in daytime SUHI intensity during summer days. Notably, ozone concentrations peaked in 2018 but have decreased annually since. Interaction analyses indicated a significant negative impact of SUHI on air quality during daytime, contrasted with a positive effect during nighttime, with ozone showing minimal influence compared to other pollutants. Further exploration across 40 cities within BTHUA demonstrated that seasonal and diurnal variations significantly modulate the effects of air quality on SUHI. This study provides a solid foundation for spatial planning and policy-making aimed at optimizing urban and suburban environments in BTHUA, highlighting the value of large-scale data and advanced statistical approaches in urban climate studies.