When the unseasonably heavy rains flooded the fields, and then the equally unseasonable heat shriveled the seeds, it did not just slash Ranjit Singh¡¯s wheat harvest by nearly half.

It put him, and nearly all the other households in his village in northern India, that much further from financial stability in a country where a majority of people scratch out a living on farms. Like many Indian farmers, Singh is saddled with enormous debt and wondering how he will repay it, as a warming world makes farming ever more precarious.

For India and other South Asian nations, home to hundreds of millions of humanity¡¯s most vulnerable, a seemingly bottomless well of challenges ¡ª poverty, food security, health, governance ¡ª has only deepened as the region bakes on the front lines of climate change.