Context

• India is increasingly grappling with the early onset and escalating intensity of heatwaves, a phenomenon that has become more pronounced over the past two decades.
• In 2025, several Indian states and cities experienced their first severe heatwave in March, 15-20 days earlier than in 2024, highlighting the growing immediacy of this environmental crisis.
• With 2024 recorded as the hottest year globally since the pre-industrial era, India stands at a critical juncture, facing both the direct health impacts of extreme heat and its wider socio-economic repercussions.

The Health Impact of Rising Temperatures

• As temperatures inch closer to the human body’s average of 37°C, the body’s ability to regulate heat diminishes, leading to heat stress.
• This condition is not just about discomfort; it affects major organs including the kidneys, liver, and brain, and can result in severe illness or death.
• Humidity and wind speed further exacerbate this impact. While the health consequences are grave, they only scratch the surface of the heatwave crisis in India.

Socio-Economic Ramifications and Inequity

• India’s heatwaves affect the nation's socio-economic structure deeply.
• Agriculture, one of the most heat-exposed sectors, suffers due to reduced productivity, crop failures, and livestock deaths.
• This disproportionally affects farmers and the rural poor, who are heavily reliant on daily physical labour.
• With 75% of India’s workforce, about 380 million people, engaged in heat-exposed labour, heat stress leads to significant job and income losses.
• Estimates suggest India loses between 3% to 5% of its GDP due to this, and in 2023 alone, about 6% of total work hours were lost because of heat stress.
• Furthermore, the most marginalised communities, women, migrants, elderly people, and subsistence workers, bear the brunt of this crisis.
• Gender norms exacerbate the burden on women, who are expected to work in poorly ventilated kitchens and wear culturally appropriate, often heat-retaining clothing.
• The spatial and social layout of urban slums often traps heat, making indoor conditions worse than outside.
• Thus, heatwaves are not just a meteorological issue but a profound matter of social inequity.

Policy Response and the Evolution of Heat Action Plans (HAPs)

• The recognition of heat as a serious public health threat began relatively late.
• Although scientists observed urban heat phenomena as early as the 19th century, it wasn’t until the early 2000s that European nations began implementing Heat and Health Action Plans (HHAPs).
• India joined this movement in 2013, when Ahmedabad became the first city in Asia to launch a heat action plan.
• Since then, over 140 Indian cities and more than 23 states have developed HAPs.
• These plans generally include five components: early warning systems, public awareness campaigns, preparation of health systems, long-term heat reduction strategies such as urban greening and cool roofs, and data-driven monitoring of health impacts.
• However, the implementation of these HAPs has been uneven, and often only partially effective.
• Success stories emerge mainly when local governments collaborate actively with public health experts, NGOs, and community-based organizations.

The Need for Improved and Inclusive Heat Action Planning

• Localized and Data-Driven Planning
  • HAPs must incorporate local vulnerability assessments, accounting for both temperature and humidity.
  • Comprehensive data collection on heat-related mortality and morbidity is essential for targeted interventions.
• Sophisticated Alert Systems: Inspired by countries like the UK, Indian cities should adopt Heat Health Alert systems that consider both daytime and nighttime temperatures and provide detailed guidance on thermal comfort levels and safer activity windows.
• Infrastructure and Urban Design
  • Building codes must promote heat-resilient infrastructure using reflective materials and designs that enhance ventilation.
  • Public spaces should be adapted with more shaded areas, parks, and accessible water points.
• Support for Informal Workers
  • Governments must consider financial aid for informal sector workers during extreme heat events.
  • Universal advisories to stay indoors may not be effective for the urban poor living in crowded, heat-trapping environments. Policies must be context-specific.
• Public Health and Workplace Adaptations
  • Municipalities should ensure the availability of drinking water and oral rehydration solutions.
  • Workplaces should implement staggered shifts and provide flexibility for early morning or late evening work to avoid peak heat hours.
• Cooling Infrastructure and Innovation
  • More cities should introduce summer shelters, akin to winter shelters, especially for the homeless and outdoor workers.
  • Initiatives like the cool roof policy being developed by some states should be scaled up nationwide.

The Way Forward: A Call for People-Centric and Equitable Approaches

• The evidence is clear, investments in heat adaptation are not only life-saving but also economically sound.
• To mitigate the impacts of rising temperatures, Indian policy must pivot towards a holistic, long-term strategy that integrates inter-agency coordination, insurance coverage for lost wages, and innovations rooted in scientific evidence.
• Above all, these efforts must be people-centric, acknowledging the disproportionate burdens on vulnerable populations and working toward equitable solutions.

Conclusion

• Heatwaves in India are not merely a seasonal inconvenience but a growing humanitarian and economic emergency.
• With average global temperatures continuing to climb, the urgency for adaptive action is greater than ever.
• Recognising the issue as one of equity and resilience will be key to protecting lives and livelihoods in the years to come.