Heatwave Hotspots: SUHI and Intra-Urban Surface Temperature Mapping in Three Argentine Cities

Abstract This study analyzes the Surface Urban Heat Island (SUHI) effect and the spatial distribution of Land Surface Temperature (LST) during heatwaves in three climatically and geographically distinct Argentine cities: Posadas, Buenos Aires, and Neuquén. Leveraging high-resolution satellite imagery (MODIS, Landsat 8, Sentinel-2) and the Local Climate Zone (LCZ) classification, the research quantifies SUHI intensity and identifies fine-scale thermal patterns across urban, peri-urban, and rural areas. Results show that all three cities experience significant SUHI effects, particularly at night, with urban areas consistently exhibiting higher LSTs than their surroundings. However, daytime patterns vary considerably. In Neuquén’s semi-arid plateau, a negative SUHI was observed, with rural areas reaching higher temperatures than urban centers. Densely built environments—especially compact zones—demonstrate elevated heat retention, exacerbating heatwave impacts. Conversely, areas with substantial vegetation, such as parks and river corridors, consistently show lower surface temperatures, underscoring their role in urban cooling. By integrating multi-source remote sensing data with the LCZ framework, this study provides a robust and transferable methodology for analyzing intra-urban thermal variability. The findings offer valuable insights for climate adaptation and urban planning, particularly in rapidly expanding cities facing increasing exposure to extreme heat. Graphical Abstract This study examines the effects of extreme heat in urban environments by analyzing the Surface Urban Heat Island (SUHI) phenomenon and the spatial distribution of Land Surface Temperature (LST) across three climatically diverse Argentine cities: Posadas, Buenos Aires (CABA), and Neuquén. The research integrates high-resolution satellite imagery (MODIS, Landsat, Sentinel) and Local Climate Zone (LCZ) classification to capture fine-scale thermal dynamics during heatwaves. The two main goals were: (1) to assess SUHI intensity in different urban contexts, and (2) to explore how surface temperature varies within cities based on land cover and built environment characteristics. The results show that densely built zones, particularly compact LCZs, experience higher LSTs both during the day and at night. Vegetated and peri-urban areas consistently exhibit lower surface temperatures, confirming the cooling role of green infrastructure. In Posadas and CABA, the SUHI effect is strongest at night, while Neuquén presents a unique case of daytime negative SUHI, especially in semi-arid rural plateaus with low vegetation and soil moisture. The findings highlight how local geography, urban morphology, and vegetation interact to shape heat exposure, emphasizing the need for spatially targeted heat mitigation strategies. These insights are particularly valuable for guiding urban planning and climate adaptation efforts in rapidly expanding cities facing growing risks from extreme heat events.