Pacific islands in danger of being obliterated by rising sea levels should seek aid for relocation at a crunch UN climate change conference in Copenhagen, a Fiji-based scientist said.

"By 2100, I don't see how many islands will be habitable," professor Patrick Nunn, a climate change researcher at the University of the South Pacific in Fiji said ahead of the opening of a regional climate change conference Monday.

Nunn is chairing the Pacific Climate Change Roundtable meeting in the Marshall Islands capital Majuro, where 14 Pacific countries and territories are devising their strategy for the December conference.

New scientific projections showed that sea levels were rising faster than the Intergovernmental Panel on Climate Change projected in its 2007 report, Nunn said.

"We're now looking at a more than one metre (three feet) sea-level rise by the end of the century," he said.

For low-lying coral atoll nations such as the Marshall Islands, Kiribati, and Tuvalu, habitation will become impossible.

"The biggest challenge is getting policy makers to understand the need for a profound change in the way Pacific people live," he said.

"Relocation is one of the most difficult things to talk about and to convince people that the home they've lived in for centuries is no longer a viable option," said Nunn, who has researched climate change for 24 years.

Mitigation and adaptation projects were being proposed for low-lying areas to withstand sea-level rise, but Nunn said "there are no real options in Tuvalu, the Marshall Islands and other atolls other than to move people."

He added the problem was not restricted to atolls.

"In most larger islands in the Pacific, there is much less concern for sea-level rise because they have a hinterland to move to. (But) it's not as easy as it sounds."

For example, in the low-lying Rewa Delta region of Fiji's main island of Viti Levu -- which has three times Tuvalu's population of around 12,000 -- people would also be affected by rising sea levels, he said.

Nunn said political leaders of countries with low-lying areas must urgently start planning for relocation.

"If relocation is to happen by 2050, then by 2020 a plan must be in place," he said.

David Sheppard, the director of the Samoa-based Secretariat of the Pacific Regional Environment Program (SPREP), told the opening of the meeting there was a need for better science and observation in the region to devise ways to adapt to climate change.

Significant funding is now becoming available from developed nations but problems associated with accessing the funds, reporting on projects and implementing them were causing problems for the tiny island nations.

Sheppard said there was a need for effective coordination between donors to ensure the best results for Pacific island countries.

Marshall Islands government chief secretary Casten Nemra called on the 14 Pacific nations and territories represented at the meeting to "speak with one voice, to be the global champion of climate change."

Nemra recalled an ocean wave surge that coincided with a high tide in December, inundating many islands in his nation.

"Seven hundred people were displaced, many houses were destroyed, one million US dollars in infrastructure was damaged and crops were damaged from salt-water intrusion," he said.