INDIAN SUMMERS ARE GETTING HOTTER, BUT IS IT THE HEAT OR IS IT US?

India once knew how to live with heat. From the mud homes of Odisha to the sandstone courtyards of Rajasthan, people designed spaces that cooled by default.

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Routines followed solar rhythms: work began at sunrise, paused during peak heat, and resumed in the evening. In cities, water-cooled courtyards, shaded alleys, stepwells, and perforated stone screens created microclimates

Every summer, a familiar question surfaces across India, echoing from homes to newsrooms: is it genuinely hotter, or have we simply become more sensitive? This isn't just some nostalgic lament or biological quirk. The evidence is clear and uncompromising: India's heat is intensifying, creeping in earlier, stretching longer, and striking deeper than ever before.

What's happening isn't a trick of perception. It's real. Heat waves, once occasional and brief, have become persistent forces reshaping daily life and work. According to the India Meteorological Department, a heat wave is declared when the temperature reaches at least 40° C in the plains or 30° C in the hills, with a deviation of 4.5° C or more above normal for at least two consecutive days.

These thresholds, once rare, are quickly becoming the standard during summer months. In states like Odisha and Rajasthan, what used to be brief seasonal heat spikes now stretch into longer, more frequent episodes, cumulatively spanning months. Between June 2010 and the summer of 2024, cumulative heat wave days soared from roughly 177 to 536-a staggering increase of over 200%.

Heat wave days count the total number of days on which heat wave conditions are recorded across all affected regions. Since heat waves strike different places at different times, these days are summed nationally, so the total may surpass the length of the summer season in any single location.

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