Shyamal Mandal lives at the edge of ruin.
In front of his small mud house lies the wreckage of what was once his village on this fragile delta island near the Bay of Bengal. Half of it has sunk into the river.
Only a handful of families still hang on so close to the water, and those that do are surrounded by reminders of inexorable destruction: an abandoned half-broken canoe, a coconut palm teetering on a cliff, the gouged-out remnants of a family’s fish pond.
All that stands between Mr. Mandal’s home and the water is a rudimentary mud embankment, and there is no telling, he confessed, when it, too, may fall away. “What will happen next, we don’t know,” he said, summing up his only certainty.
The sinking of Ghoramara can be attributed to a confluence of disasters, natural and human, not least the rising sea. The rivers that pour down from the Himalayas and empty into the bay have swelled and shifted in recent decades, placing this and the rest of the delicate islands known as the Sundarbans in the mouth of daily danger.
Certainly nature would have forced these islands to shift size and shape, drowning some, giving rise to others. But there is little doubt, scientists say, that human-induced climate change has made them particularly vulnerable.
A recent study by Sugata Hazra, an oceanographer at Jadavpur University in nearby Calcutta, found that in the last 30 years, nearly 31 square miles of the Sundarbans have vanished entirely.
More than 600 families have been displaced, according to local government authorities. Fields and ponds have been submerged. Ghoramara alone has shrunk to less than two square miles, about half of its size in 1969, Mr. Hazra’s study concluded. Two other islands have vanished entirely.
The Sundarbans are among the world’s largest collection of river delta islands. In geological terms they are young and still under formation, cut by an intricate network of streams and tributaries that straddle the border between India and Bangladesh. Ever since the British settled them 150 years ago in pursuit of timber, the mangroves have been steadily depleted — half of the islands have lost their forest cover — and the population has grown....