As the calendar flips to May, India’s major metropolitan cities are experiencing a surge in temperatures, with Delhi, Mumbai, Chennai, and Bengaluru all recording high mercury levels. The phenomenon is not merely a seasonal shift but is closely linked to the urban heat island effect, significantly impacting urban environments.
The urban heat island effect describes a situation where urban areas exhibit higher temperatures compared to their rural surroundings. This disparity arises primarily due to human activities and the infrastructure in cities, which absorb and retain heat more efficiently than natural landscapes.
Causes and Effects
•Urban areas, with their abundance of concrete and asphalt, absorb heat during the day and release it slowly, leading to elevated temperatures, particularly at night.
•The scarcity of plants, trees, and green areas in cities reduces natural cooling through shade, exacerbating the urban heat island effect.
• Metropolitan cities have higher energy demands for transportation, industry, and air conditioning, all of which release heat into the air, further contributing to the heat island effect and straining energy resources.
•The clustering of buildings restricts airflow, creating heat-trapping spaces between structures and raising temperatures.
•Urban heat islands are associated with poorer air quality due to increased pollutant concentration, impacting both human health and the environment.
•While not directly causing climate change, urban heat islands can exacerbate it by elevating temperatures in urban areas and beyond.
•High temperatures in urban areas lead to increased energy demands for cooling, potentially causing power outages during peak periods.
Differentiating Heat Islands and Climate Change
While heat islands and climate change are distinct phenomena, they are interconnected. Heat islands result from localized urban conditions, whereas climate change involves long-term global warming due to greenhouse gas emissions. However, heat islands can exacerbate the impacts of climate change by intensifying heatwaves and other extreme weather events in urban areas.
