Haldar, a meticulously dressed widow of about 50, had at least had some inkling of what was to come. She'd watched as the nearby Sundarbans, a vast mangrove forest that flanks the village, had retreated, its trees looking increasingly weedy. She'd noted how the water appeared to draw strength from the forest's weakness. The only surprise, Haldar insisted, is that the village's earthworks held out for so long. "The trees defended us, but we treated them very badly," she said. "So now we are all suffering the consequences."

In Bangladesh and the neighboring Indian state of West Bengal, there are thousands of villages like East Dhangmari -- places that are losing their natural defenses against climate change just as it is intensifying. The land is paper-flat and crisscrossed by rivers bulging with meltwater from the Himalaya. Cyclones frequently roar in off the Bay of Bengal, sometimes killing thousands. Flooding is pervasive.