Indian summers are becoming hotter, but have we lost our adaptability?

• Heat waves in India are becoming more frequent and severe, affecting daily life and work.

• Heat waves are defined as temperatures reaching at least 40 degrees Celsius in plains or 30 degrees Celsius in hills, with a deviation of 4.5 degrees Celsius or more above normal for at least two consecutive days.

• Between June 2010 and the summer of 2024, cumulative heat wave days soared from roughly 177 to 536, a 200% increase.

• Heat wave days count the total number of days on which heat wave conditions are recorded across all affected regions.

• Despite the increasing severity of heat waves, official data likely underrepresents their true impact due to variations in heat-related deaths.

• Excess mortality analysis, comparing actual deaths during heatwave periods with long-term seasonal averages, is a widely accepted and robust epidemiological tool.

• The 2022 heatwave reduced wheat yields in key producing regions by approximately 4.5%, contributing to inflationary pressures on food commodities worldwide.

• The heatwave triggered a power crisis, straining the grid and causing blackouts in some areas. Labour productivity in outdoor sectors suffered dramatically.

• Heat-related productivity losses could jeopardize between 2.5% and 4.5% of India’s annual Gross Domestic Product by 2030, underscoring the urgent need for adaptive policies.

• Despite the challenges, India once knew how to live with heat, with traditional practices like Navtapa, meaning “nine days of heat,” aligning closely with modern heat wave data.

Modern Development Models and Heat Risk in India

• Post-liberalisation planning favored speed and scale, often overlooking climate sensitivity.

• Glass façades and concrete homes replaced breathable structures.

• Labour shifted from flexible agricultural cycles to more rigid, outdoor, informal urban jobs.

• Planning codes like the National Building Code don’t mandate passive cooling.

• Real-estate finance rarely supports traditional materials.

Invisible Heat-Related Mortality in India

• Ahmedabad’s heat action plan in 2014 has significantly reduced heat-related mortality.

• Cities like Bhubaneswar and Nagpur have initiated efforts to increase green cover and promote rooftop measures.

• Many heat action plans remain advisory, lacking binding mandates, dedicated budgets, or clear accountability mechanisms.

• Only a few cities have appointed trained climate officers or integrated heat considerations into their urban master plans.

• Rural heat governance framework is lacking, with key programmes barely touching on heat issues.

Communicating Heat Risk

• A deeper gap persists between science and how people actually experience heat.

• Public health messages rarely translate the “feels like” temperature into everyday terms.

• Heat alerts should be delivered through oral announcements, local radio, posters, community workers, and trusted institutions in regional languages.

• Inclusive communication must reach every corner, every community.

• Districts can start rolling out heat action plans tailored to their realities.

• National programmes like the Pradhan Mantri Awas Yojana, the Mahatma Gandhi National Rural Employment Guarantee Act, and the National Health Mission offer a canvas to embed climate sensitivity.

• Real transformation demands more than isolated efforts. Building codes must evolve to favour passive cooling, urban and rural designs should be inclusive by default, and institutions must learn to speak the same language.