Anthropogenic heat amplification in industrial zones: Unraveling heat stress risk heterogeneity in river-sea dual-core cities

Abstract

River-sea dual-core cities exhibit marked climatic disparities between coastal and inland zones. A comprehensive analysis is therefore needed to reveal how urban form, geography, and industry jointly shape heat stress. Taking Tianjin as a representative case, this study employs an integrated approach that combines multi-source remote sensing, field surveys, and a dense meteorological station network to develop a practical assessment framework for these complex thermal dynamics. Our findings reveal three distinct thermal regimes governed by different mechanisms: compact urban cores experience intense dry heat driven by building density; coastal areas face significant humid heat stress due to marine influence and sea breeze dynamics; and specialized industrial zones create thermal anomalies that transcend conventional local climate zone (LCZ) classifications. The research demonstrates that while LCZ framework captures urban morphological variations, it requires substantial refinement to incorporate geographical context and industrial processes. Notably, our case study of the Wangkou industrial cluster shows that intensive energy consumption generates an average anthropogenic heat flux of 6.7–8.9 W/m², substantially reshaping local microclimates. This pattern challenges conventional urban classification systems. In response to these distinct thermal regimes, we recommend implementing zonal mitigation strategies, including cool infrastructure in urban cores, ventilation corridors in coastal areas, and specialized thermal regulations for industrial zones. This study proposes a transferable framework for assessing urban heat risks and offers scientific support for spatially-optimized, climate-resilient planning in similar cities globally.