Evaluation of Environmental and Anthropogenic Factors on Urban Heat Island: The Case of Istanbul, Turkey

Year 2025, Volume: 12 Issue: 4, 368 - 397, 12.01.2026

Büşra Begen Okay , Azem Kuru

https://doi.org/10.26650/ijegeo.1795321

https://izlik.org/JA89JY29LP

Abstract

This study aims to evaluate the urban heat island (UHI) phenomenon in Istanbul and the environmental and anthropogenic factors that may contribute to its formation. Air temperature, relative humidity and wind data for the period 1970-2023 provided by the Turkish State Meteorological Service (TSMS) and population, number of motor vehicles and electricity consumption data provided by the Turkish Statistical Institute (Turkstat) are analysed. TSMS data reveals that long-term temperatures in Istanbul show a linear upward trend, especially in January and July. This trend shows that annual average temperatures have increased from 13-14°C to 15-16°C in a period of approximately 50 years, increasing the importance of the urban heat island effect in the context of global climate change. When urban and rural meteorological stations are compared, it is determined that the temperature values differ by approximately 2-4 °C and the UHI is spatially observable in Istanbul. However, no statistically significant relationship was found between annual anthropogenic indicators such as population growth, number of motor vehicles and electricity consumption and air temperature values. This result shows that UHI cannot be explained by annual macro-indicators, but is rather influenced by micro-scale morphological conditions, surface features and settlement pattern. While the study reveals the existence of the UHI effect in Istanbul and the temperature increase spread over many years, it shows that the causal relationship of anthropogenic factors with UHI at the annual level is limited. These findings suggest that enhancement of green areas, protection of wind corridors and micro-scale urban design strategies are critical for mitigating UHI.

Keywords

Urban heat island , global warming , climate change , Istanbul , Turkey

Kentsel Isı Adası Üzerinde Etkili Olan Çevresel ve Antropojenik Faktörlerin Değerlendirilmesi: İstanbul – Türkiye Örneği

https://izlik.org/JA89JY29LP

Abstract

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