India, March 26 -- There is a dangerous gap between what climate models are telling policymakers and what is actually unfolding on the ground across India's cities. That gap is not a rounding error. It is a matter of life and death for tens of millions of people, and it is widening with every passing summer.

It is only March, yet soaring temperatures across large parts of India are already testing human endurance, an early warning of what the months ahead may hold. Over the past four decades, India's average surface temperature has already risen by about 1degC. With a large share of its population concentrated in already warm regions, the country faces some of the highest levels of human exposure to extreme heat anywhere in the world.

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