(CNN) -- There is one holiday destination that should shake the faith of even the most vehement climate change skeptic: the Carteret Islands, part of Papua New Guinea, located northeast of Bougainville.

The Carteret Islands are just one of a number of places already feeling the effects of climate change.

The palm trees sway gently under a balmy sun, the beaches are perfect, and stretched out as far as the eye can see is the wide blue of the Pacific Ocean.

The only problem with this idyllic scene is that the water is getting closer; slowly but surely, as global warming bites and sea levels rise, the islands are being swallowed up, leaving the few hundred inhabitants pondering an uncertain future.

"King tides and sea surges are floodling the island to a knee high and it is difficult for the salt water to dry up," says Ursula Rakova, a Carteret islander and campaigner.

"Fruit trees and nut trees have lost their leaves and only skeleton branches are left standing. The only greenery is from coconut and sago palms... People have no garden food to feed on... We have lost more than 60 percent of our land already."

The problem is that on the Carteret Islands, a horseshoe shaped scatter of small islands around a central lagoon, nowhere is more than 1.2 meters above sea level.

If anywhere was the canary in the mine forewarning us of the disaster predicted in low lying areas of the world if runaway climate change takes hold, it's right here.

Rakova says there is a growing dependency culture on the island as people rely on international aid for food, which is destroying the social and cultural fabric of the Carterets.

"This is a state of emergency," she says. "Why are the rich nations ignoring the fate of the Carterets Islanders? Are the rich nations waiting for the islanders to float before they can act and put money where their mouths are in terms of human rights?"

It's a cruel irony that the people with some of the lowest carbon footprints are already paying the price for the emissions of far richer countries, and are forced to leave their homes for an uncertain future. But the Carteret Islanders aren't alone.

Environmentalists point to Inuit communities threatened by melting ice in Greenland, and those living around the fast-shrinking Lake Chad in Africa, as among many already feeling the effects.  Watch the effects of warming temperatures on Arctic ice »

"The issue of environmental refugees promises to rank as one of the foremost human crises or our time," says British environmentalist and Oxford University professor Norman Myers, who has published extensively on the subject.

A report by Friends of the Earth in 2007 identified communities all over the world, from Brazil and Honduras, to Malaysia, Mali, Peru and even the UK, that were directly under threat from a mix of drought, rising sea levels, other extreme weather and disease.

Climate refugees: Causing controversy

As much of the primary research on our future climate looks increasingly gloomy -- and privately some scientists will make far blacker predictions than they publish - the world seems faced with a growing challenge.

Experts at the climate change conference in Copenhagen in March issued a stark warning when they revised up the scale of projected sea level rises, saying many coastal areas around the world could be completely inundated by 2100.

"It is now clear that there are going to be massive flooding disasters around the globe," said Dr David Vaughan, of the British Antarctic Survey, in Copenhagen.

As well as low-lying areas of Bangladesh and the Maldives, the scientists warned that the Netherlands could face catastrophic floods, and large areas of Florida and the UK, including the Thames Estuary, may disappear under the waves.

But despite the threat of widespread future problems -- and the reality of life for the Carteret Islanders now - the term "environmental refugees" remains controversial.

Some NGOs, such as Greenpeace, have spoken in terms of 150 million displaced people being driven from their homes by 2050 as climate change makes their lives impossible. Their figures are backed by
What is predicted to rise? What do the Carteret Islands lose land to? What number of islanders need to be evacuated? Where is Carteret Islands? Where is pressure from climate change most intense? What negative effects do many areas feel?
sea levels "King tides and sea surges 150 million Papua New Guinea, Carteret Islands water is getting closer; slowly but surely, as global warming bites and sea levels rise, the islands are being swallowed up, leaving the few hundred inhabitants pondering an uncertain future.
question: What is predicted to rise?, answer: sea levels | question: What do the Carteret Islands lose land to?, answer: "King tides and sea surges | question: What number of islanders need to be evacuated?, answer: 150 million | question: Where is Carteret Islands?, answer: Papua New Guinea, | question: Where is pressure from climate change most intense?, answer: Carteret Islands | question: What negative effects do many areas feel?, answer: water is getting closer; slowly but surely, as global warming bites and sea levels rise, the islands are being swallowed up, leaving the few hundred inhabitants pondering an uncertain future.