Paris - People living in small island nations set to be submerged under rising seas will face legal problems as they attempt to migrate to dry land, United Nations climate experts said on Wednesday.Ice melt caused by a warming atmosphere is making sea levels rise, which will cause problems globally - but perhaps nowhere more acutely than the low-lying islands of Kiribati, Tuvalu and Nauru in the South Pacific Ocean.A survey conducted by the United Nations University's Institute for Environment and Human Security, presented at a global climate summit in Paris, showed that people in all three countries - whose combined population is 124 000 - have already started migrating in search of dry land.Fifteen and 10% of the population on the tiny islands of Tuvalu and Nauru already migrated internationally. In Nauru, surveys showed that 40% of households "feel that migration will be a likely response if sea level rise or flooding worsens".Kiribati, whose president said during opening remarks on Monday that his country has already started establishing plans for mass migration to Fiji, has had 1.3 % of its population move internationally and 7.7% move internally. Problems related to climate were the second most-cited reason to move.Climate refugeesBut UN expert Koko Warner warned that climate refugees don't fit within global legal migration rules, making it more difficult for people fleeing adverse weather patterns caused by climate change and leaving people in legal limbo.Economic migrants searching for work can apply for visas, and refugees fleeing persecution can qualify for asylum under the Geneva Convention's rules on refugees.Warner said even while countries like Sweden and Germany are stepping up their efforts to accommodate refugees leaving conflict zones like Syria, more people will be forced to leave their homes as local and regional climates change due to global warming.Already in the three islands, 7 to 9% of the population wanted to migrate, but could not, according to the surveys. The biggest climate-related problems were sea-level rise, drought, and what experts called "saltwater intrusion" that made it more difficult for people to keep fresh water protected.While the surveys focused on the three islands, other nations in the region have called for greater action to help them cope with what they say is an imminent disaster."Where and when can we as a leaders of the world tell our people that this ... suffering, this sheer madness, this climate atrocity will end?" said Vanuatu Deputy Prime Minister Claude A Emelee."How can I but express profound disbelief that scientist evidence proves that the climate system is warming and that human influence on the climate system is clear, but appropriate response is lacking?" he said.The IPCC, a consortium of global scientists who have put out regular reports on climate change, have anticipated a possible 1-metre sea level rise by 2100. The UN Environment Programme has said that would put a third of the population in low-lying island states at risk.US supportEarlier this week, US President Barack Obama expressed his support for the plight of the islands."These nations are not the most populous nations, they don't have big armies ... but they have a right to dignity and sense of place and their voice is vital in making sure that the climate agreement that emerges here in Paris in not just serving the interest of the most powerful," Obama said after meeting with island leaders.Negotiators in Paris are trying to hammer out a global agreement to limit warming to 2°C by setting ceilings on the amount of carbon emissions countries can produce.During the meeting, Obama pledged $30m toward a "climate risk insurance initiative" to help vulnerable countries cope with a changing climate and its impacts.But Emelee said that a broader shift had to take place, calling for an immediate end to coal plants worldwide."We must develop our ethic of compassion for this planet as there is no alternative," he said. "Vanuatu has no alternative. This small island, our home, our garden, our coral reef and the very essence to our livelihood. What the profiteers of this Earth are doing to the people of Vanuatu is tragic, unacceptable and morally wrong. The fossil fuel way of life must end now."