MAJURO ATOLL, Marshall Islands -- Valentino Keimbar hides from the intense heat in the shade of a breadfruit tree, waiting for his basketball game to begin. It was supposed to start a couple of hours ago, maybe three, but time matters little here on the Marshall Islands.

Keimbar would love to stay on this tiny string of atolls in the vast Pacific Ocean, which he considers a precious gift from his ancestors. But he fears hotter weather and rising seas may soon force everyone to go, and that many will choose an unlikely place 6,000 miles (nearly 10,000 kilometers) away: Springdale, Arkansas.

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For more than three decades, Marshallese have moved in the thousands to the landlocked Ozark Mountains for better education, jobs and health care, thanks to an agreement that lets them live and work in the U.S. This historical connection makes it an obvious destination for those facing a new threat: global warming.

Keimbar, 29, last year traveled to Springdale seeking medical treatment for his 6-year-old son. Now he's considering moving permanently to secure a solid future for his children.

"Probably in 10 to 20 years from now, we're all going to move," he said.

Climate change poses an existential threat to places like the Marshall Islands, which protrude only 6 feet (2 meters) above sea level in most places. King tides, when the alignment of the Earth, moon and sun combine to produce the most extreme tidal effects, and storm surges are getting worse, resident say, causing floods that contaminate fresh water, kill crops, and erode land. As a result, some Marshallese think an exodus as inevitable, while others are planning to stay and fight.

Foreign Minister Tony de Brum is a vocal advocate for keeping global warming to a minimum, a position he'll be pushing when world leaders meet in Paris next week seeking a way to limit fossil fuel emissions.

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Growing up on the lagoon, de Brum said, he loved catching rabbitfish off Enebok Island, which was lush with coconut and breadfruit trees. But in recent years, the small, uninhabited island has slipped beneath the water. At low tide, all that remains is an exposed pile of rocks that snags flotsam: a black sandal, some frayed green rope, a coconut sprouting a green shoot.

And in July, he recounted, lagoon waves whipped up by unusual winds swept a large yacht within a few feet of his bedroom window, and then beached it nearby.

De Brum said even a small rise in global temperatures would spell the demise of his country of 70,000. While many world leaders in Paris want to curb emissions enough to cap Earth's warming at 3.6 degrees Fahrenheit (2 degrees Celsius), de Brum is pushing for a target that's 25 percent lower.

"The thought of evacuation is repulsive to us," he said. "We think that the more reasonable thing to do is to seek to end this madness, this climate madness, where people think that smaller, vulnerable countries are expendable and therefore they can continue to do business as usual."

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The Marshallese who choose to leave have settled in Hawaii, Oklahoma and the Pacific Northwest, but Springdale has the most on the U.S. mainland and has taken on a special significance. Their numbers there have expanded to 6,000, nearly one-tenth of those who remain back home. Some jokingly call it "Springdale Atoll," and there's even a Marshallese consulate, the only one on the mainland U.S.

The pioneer was a man named John Moody, who moved in 1979 seeking an education and stayed for a job at Tyson Foods, one of the world's largest processors of chicken. Family and friends followed, and the population of Marshallese swelled after 1990.

"Arkansas is the land of opportunity," said Josen Kaious, from the Marshall Islands town of Laura, who's lived in Springdale before and plans to move back next year. "You can help your family, and do whatever you want."

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Carmen Chong Gum, the Marshallese consul general in Springdale, said while people still move for better jobs and health care, some are now citing climate change as a factor.

Gum works in a two-story building just off downtown's main street. It's decorated with a U.S. map with push pins marking where Marshallese live, a bulletin board listing job opportunities, and posters depicting medicinal plants and tropical fish found in the Marshall Islands.

Her people now even have their own newspaper. The first edition, published this fall, was written entirely in Marshallese and featured half-page advertisements for Marshall Islands political candidates because Springdale residents can vote absentee.

Many candidates spent months campaigning in Springdale. One was Alfred Ned, who hoped to pick up votes with his pledge to convince Japan and the U.S. to clean up the trash they left on his atoll during World War II.

Gum said she tries to help people understand what's expected of them in their new country: Enrolling their kids in school. Not parking on the grass. Not making too much noise. Paying their utility bills on time. She said people tend to be much more relaxed about enforcing rules on the Marshall Islands.

There are also more serious challenges for those who move. While the agreement with the U.S. allows Marshallese to live and work in the U.S., they don't automatically become citizens, and most aren't eligible for welfare. That can result in hardship for any who suffer a serious illness or lose a job.

Life is sometimes hard in any case.

At the Tyson poultry plant where she works, Daisy Loeak has about two seconds to scan each freshly-killed Cornish hen that comes down the production line to decide if it's of premium quality. Any flaw like a bruised wing or a broken leg means it should be sold at a discount.

She routes the hens onto conveyor belts before they're packed into boxes and flash-frozen. Out of 300 workers at the plant, Loeak is one of about 120 Marshallese. She moved to Springdale in 2008 with her grandparents, who traveled to the U.S. for a funeral and ended up staying.

"It's Chickendale, not Springdale," said Loeak, whose real name is Daisina, but who adopted a version that's easier for Americans to pronounce. She wells up with tears as she talks about rising sea levels, and says she misses her homeland.

"In the Marshall Islands, it's just more carefree," she said. "You go where you want."

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Those who stay face their own challenges. At the Rita graveyard in Majuro, where many of his relatives are buried, Carlon Zedkaia watched in February as a king tide swept in and washed up against the base of gravestones, collapsing some and exposing human remains.

The tide flooded his nearby home, and he worries one day it will sweep right across from the sea to the lagoon, flooding all the land. He's upset about the damage to the graveyard and worries there will be no spot for him to be buried there.

"It's not our fault that the tide is getting higher," he said. "Just somebody else in this world that wants to get rich."

Poet Kathy Jetnil-Kijiner said the world needs to save her islands to save itself - that if the atolls are allowed to slip beneath the waves, the rest of the Pacific and the U.S. coastline would be next.

"What will happen to our culture? What will happen to our stories? What will happen to thousands of years of history?" she said. "What will happen to the next generation? They won't know where they're from. They'll be rootless. They'll just be wandering. And I don't want that to happen at all."

In August, the 600 residents on the small island of Kili effectively raised a white flag after the island was repeatedly buffeted by storms and flooding, sometimes cutting off residents completely from the more populous atolls.

The islanders are descendants of the Bikini atoll residents who were moved to make way for U.S. nuclear testing after World War II. They are now petitioning Washington to allow them to spend their resettlement trust fund money abroad, an option that would allow them to move to Arkansas or anywhere else they choose.

The U.S. seems amenable, said Jack Niedenthal, the Bikini trust liaison, but has yet to take the required Congressional action. Niedenthal said that while he will fight to stay, he sees an eventual evacuation of the Marshall Islands as almost inevitable.

"In the end it's like 60,000 people against 8 billion," he said. "And I don't know how you get the rest of the world to change their habits."

For some, the notion of exactly what constitutes a homeland is becoming fluid.

Sheldon Riklon, a Marshallese doctor who lives in Hawaii, said he's always wanted to return home to serve his people.

But after visiting Springdale last year, he's expanded his definition of the Marshall Islands to include Arkansas, and is considering moving there instead. He's encouraged by the potential of the Marshallese youth, many of whom are succeeding at school. And he said the friendliness of Arkansas may in the end be the thread that connects it to home.

"It definitely wasn't what I expected. I mean, besides the weather. It really opened up my eyes to the kindness of people there," he said. "It's really similar to the Marshallese lifestyle, and the way of dealing with visitors, in that they were very welcoming."

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Kissel reported from Springdale, Arkansas.

EDITOR'S NOTE: This story is part of an occasional series focusing on the science, the costs and the challenges of climate change around the world ahead of a critical summit in Paris.