By Matt McGrath
BBC News, Copenhagen
Coral reefs are a key source of food, income and coastal protection
The prospects of saving the world's coral reefs now appear so bleak that plans are being made to freeze samples to preserve them for the future.
A meeting in Denmark took evidence from researchers that most coral reefs will not survive even if tough regulations on greenhouse gases are put in place.
Scientists proposed storing samples of coral species in liquid nitrogen.
That will allow them to be reintroduced to the seas in the future if global temperatures can be stabilised.
Legislators from 16 major economies have been meeting in the Danish capital, Copenhagen, to try to agree the way forward on climate change.
The meeting has been organised by the Global Legislators Organisation for a Balanced Environment (Globe).
Losing the fight
One of the issues they have been considering is what to do with coral reefs, which make up less than a quarter of 1% of the ocean's floor.
Yet the reefs are a key source of food, income and coastal protection for around 500 million people worldwide.
At this meeting, politicians and scientists acknowledged that global emissions of carbon dioxide are rising so fast that we are losing the fight to save coral and the world must develop an alternative plan.
Freezing samples for the future may be a necessary option.
''Well it's the last ditch effort to save biodiversity from the reefs which are extremely diverse systems," said Simon Harding from the Zoological Society of London (ZSL).
"It would take other work to try and reconstruct the reef so that you can start the process of building up a reef again," he said.
"That is something that needs to be looked at in detail, but we can definitely store the species and save them in that way."
According to recent research, one of the world's most important concentrations of coral - the so-called Coral Triangle in South East Asia - could be destroyed by climate change before the end of this century with significant impacts on food security and livelihoods.