Urban Heat Islands in Bulgaria during the Heatwave of July 2024

This research paper investigates the Urban Heat Island (UHI) phenomenon in Bulgaria during the extreme heatwave event in July 2024, using high-resolution ECOSTRESS satellite data from the International Space Station. The analysis focuses on mapping and visualising temperature variations across major urban centres in the country. The data cover 26 of 27 capitals of regions, highlighting the pronounced UHI effect in densely populated and industrial areas. The findings reveal that urban regions consistently exhibit higher surface temperatures, particularly during nighttime, compared to surrounding rural and mountainous areas, which benefit from natural cooling effects. Cities like Sofia, Plovdiv, and Stara Zagora show substantial heat retention, whereas cooler profiles are observed in areas like Smolyan, due to higher altitudes and forest cover. The study also relates these results to demographic data from the latest population census. It identifies a concerning trend of population decline in rural regions, while urban areas face environmental stresses from heat accumulation. Recommendations include enhancing green infrastructure, promoting sustainable urban development, and focusing on rural revitalisation to mitigate the dual challenges of population loss and heat-related environmental risks. These insights are critical for improving resilience to future heatwaves in Bulgaria.