Integrating Satellite Data, Modeling, and Citizen Science to Derive Critical Insights into Urban Dynamics

Urban regions across the Great Lakes basin (USA) and the West Midlands/South Wales (UK) are undergoing rapid land-use transitions that intensify heat and hydrologic stresses. We develop a transferable, physics-informed framework that mosaics multi-sensor satellite imagery (Sentinel/Landsat; 10–20 m; 5–16-day revisit) to derive NDVI, NDWI, NDBI, LST, and flood masks and to map a composite urban heat island (UHI) proxy. Applied to Milwaukee, Detroit, Chicago, Cleveland, and Pittsburgh, and to Birmingham, Coventry, Wolverhampton, Cardiff, Swansea, and Newport, the workflow yields internally consistent cross-city diagnostics. Great Lakes cities exhibit higher built intensity (NDBI ≈ 0.30–0.35) and warmer surfaces (mean LST ≈ 29–31 °C) e.g., Detroit 30.1 °C; Chicago 29.5 °C with non-trivial flood exposure (≈ 9–14% of urban extent: Chicago 12%, Milwaukee 11%, Detroit 14%, Cleveland 10%, Pittsburgh 9%). UK cities are cooler and less flood-exposed overall, with lower built intensity (NDBI ≈ 0.24–0.29), mean LST ≈ 25–27.8 °C, and smaller flood fractions (≈ 6–10%); Birmingham shows the highest NDWI (0.68), while Coventry/Wolverhampton/Cardiff/Swansea/Newport have NDVI ≈ 0.36–0.40 and NDWI ≈ 0.47–0.52. Cross-index screening isolates priority zones ~ 18–22% of the combined urban area where low greenness (NDVI < 0.30), concentrated imperviousness (NDBI > 0.35), and limited surface-water signal (NDWI < 0.20) co-occur with the highest LST (> 30 °C) and elevated flood susceptibility; these hotspots consistently align with industrial waterfronts, logistics yards, and freeway corridors. Satellite diagnostics are designed to interface with WRF and SWMM for scenario testing and will be augmented with resident reports from U.S. 311 and UK council portals to refine validation. By ranking intra-urban risk with minimal city-specific tuning, the framework provides actionable evidence for targeted greening, cool-materials retrofits, and distributed stormwater controls, supporting climate-resilient urban design across diverse city contexts.