Introduction

• As India grapples with an intensifying heatwave, its cities, including the capital Delhi, have turned into dangerous “heat traps.”

• The India Meteorological Department (IMD) has forecast above-normal temperatures for June in the northwest and central parts of the country, with Delhi enduring one of the longest heatwave spells in recent history.
• Delhi is currently facing record high temperatures, both day and night, increasing health risks and showing the severe impacts of climate change and urbanization.
• This June, Delhi recorded its highest minimum temperature since 1969 at 35.2 degrees Celsius, highlighting the city’s struggle with extreme heat.

Record-High Temperatures and Heatwave Spells

• Since May 12, Delhi’s daily temperatures have consistently stayed above 40 degrees Celsius, and they are not expected to drop below this mark until June 26.
• The IMD’s heatwave criteria start with 40 degrees in the plains and 30 degrees for hilly regions.
• Recently, the capital recorded a temperature of 44 degrees Celsius, which felt like 49.2 degrees due to high humidity.
• This prolonged heatwave is partly attributed to climate change and unchecked urban development, which have reduced natural cooling sources like wetlands and permeable surfaces.

Rising Night Temperatures: A New Concern

A new and alarming trend is the rise in night temperatures. This June, Delhi recorded its highest minimum temperature since 1969, with nighttime temperatures reaching 35.2 degrees Celsius.

• The concept of a ‘Warm Night,’ as defined by the India Meteorological Department (IMD), is when the minimum temperature at night exceeds the normal by 4.5 to 6.4 degrees Celsius.
• A ‘Severe Warm Night’ is characterized by a departure from the normal of more than 6.4 degrees Celsius, provided the daytime temperature is 40 degrees Celsius or more.
• Recently, Delhi experienced minimum temperatures 8 degrees above normal, with maximum temperatures soaring to 43.6 degrees Celsius.
• From June 1 to June 19, Delhi experienced 12 nights with minimum temperatures above 30 degrees Celsius, a pattern not seen since 2011.
• In 2018, another exceptionally warm June, there were 10 such days. The normal minimum temperature for this period is 27.5 degrees Celsius, indicating a significant deviation from the norm.

Health Implications

• Continuous high temperatures, particularly at night, pose significant health threats.
• The lack of nighttime cooling means people remain under heat stress throughout the day and night, increasing the incidence of heat strokes.
• The situation is aggravated as homes retain heat at night, providing little relief from the daytime heat, forcing residents to endure oppressive conditions both indoors and outdoors.

Mitigation and Adaptation Strategies

• In response to the rising temperatures, many Indian states have implemented heat action plans, including provisions for drinking water, improved medical facilities, and rescheduling outdoor work and school vacations. However, long-term strategies are crucial for sustainable urban living. The Centre for Science and Environment (CSE), emphasizes the need for comprehensive strategies such as increasing heat insulation in buildings, developing shelters for the urban poor, and investing in cooling water bodies. Financial backing is essential for these strategies. The Council on Energy, Environment, and Water points out that cities often struggle with budget constraints, making it challenging to implement effective heat mitigation measures.

Conclusion

As Indian cities continue to grow, balancing development with sustainable practices is imperative to create livable environments resilient to climate change. Immediate and long-term strategies, supported by adequate financial resources, are crucial to mitigate the impact of extreme heat and protect the health and well-being of urban residents.