Spatiotemporal dynamics of urban heat island effect and air pollution in Bengaluru and Hyderabad: implications for sustainable urban development

Abstract

Abstract Uncontrolled growth in population is the cause of the unplanned, rapid, and unsustainable expansion of urban areas. This has led to a deterioration of environmental conditions for both global and local ecosystems. This research investigates the Urban Heat Island (UHI) phenomenon in Bengaluru and Hyderabad, India, including its spatial and temporal distribution and relation to air pollution. The investigation was conducted in both study locations during the summer and winter seasons, with data spanning from 2001 to 2021. The findings reveal that the maximum UHI intensity in both cities varies seasonally, with the highest values observed during the summer and the lowest during the winter. Annual maximum UHI intensities range from 4.65 °C to 6.69 °C in Bengaluru and from 5.74 °C to 6.82 °C in Hyderabad. The average UHI intensity also exhibits seasonal and annual variations, with the UHI effect being particularly pronounced in Bengaluru. In addition, the study provides the Urban Thermal Field Variance Index (UTFVI), which reveals that both cities consistently face intense UHI impacts throughout the year, greatly affecting the quality of life. Additionally, hotspot analysis reveals an increasing trend in UHI-affected areas over the years in both cities. The study also highlights air pollution concentrations and shows relationships between land surface temperature (LST) and air pollutants, emphasizing the need to alleviate urban heat, enhance air quality, and promote sustainability. This underscores the importance of UHI dynamics in urban environmental management and public health. This study enhances comprehension of UHI dynamics in swiftly urbanizing areas, providing a novel viewpoint on the complex interconnection between urbanization, climate, and air quality. These insights help develop sustainable urban strategies, reducing the negative effects of uncontrolled urbanization and benefiting local communities and the global ecosystem.

Keywords

• Land surface temperature
• Urban heat island effect
• Urban thermal field variance index
• Air pollution
• Climate change