A GREAT MIGRATION: Increasingly severe floods, cyclones and other climate-related changes have already forced the migration of many. Here a woman wades through a flood in Dhaka, Bangladesh.
FLICKR/SUMAIYA AHMED

The first in a series of stories on Bangladesh and climate migration.

HARINAGAR, BANGLADESH—One by one, the men in Gaurpodomando's family walked out of this mud-caked village and never returned.

First, his uncles went. Both fishermen, they suffered as their catch declined year after year, before they crossed illegally into India to find work in construction. His brothers earned so little fishing that they braved tiger attacks in the nearby Sundarbans forest to forage for honey and timber. Finally, they left, too, and brought their father with them.

Now, Gaurpodomando, who said he is about 35 years old and who goes only by his first name, is the last man in his family still living in the waterlogged village along Bangladesh's Indian border.

His brothers still don't know about the angry tidal flood that burst through a dam and swallowed the family home and dozens of others in September. Those who live here say that between the disappearing fish, brackish floodwaters destroying the rice fields and the ever-fiercer cyclones that seem to inhale entire villages, life is becoming almost unbearable.

But Gaurpodomando, who earns the equivalent of $1.50 a day standing hip-deep in the salty river casting a net to collect shrimp fry, said he is doing everything he can to hang onto his way of life.

"I do feel a little lonely and sad, but I don't really want to go to India," he said, squatting on the outdoor stoop of what was once the family kitchen but is now the only structure left to shelter him, his wife and their two children. His arms and bare feet are streaked with the slate-gray mud that covers the ground and seems never to dry.

'I don't want to leave this country'

"I don't want to leave this place," Gaurpodomando said. "I don't want to leave this country. I love this place."

One day soon, Gaurpodomando and an untold number of others in Bangladesh and around the world may no longer have a choice.

A growing body of evidence, including analyses from military experts in the United States and Europe, supports the estimate that by midcentury, climate change will make vast parts of Africa and Asia uninhabitable. Analysts say it could trigger a migration the size of which the world has never before seen.

Some of the big questions remain unanswered: How many people will really move? Where will they go? How will they go? Will they return?