Reef at forefront of CO2 battle

UK scientists say it's now so badly damaged that another hurricane would simply sweep it away.

But they don't primarily blame hurricanes for the damage to the coral here on the Belize Barrier Reef; they blame climate change.

And they are backing a petition pressing the United Nations World Heritage Sites Committee to acknowledge that climate change is already damaging world heritage sites.

The five sites are the Belize Barrier reef, at 321km (200 miles) long, the biggest in the western hemisphere; the Australian barrier reef; and glacier parks in Nepal, Peru and the Rockies where glaciers are disappearing as the climate warms.

The World Heritage Sites Treaty stipulates that listed sites should not be damaged by signatories to the treaty, but it was mainly designed to protect the world's treasures in the event of wars.

The stakes are high because if the UN accepts the case, it might lead to poor countries attempting to sue rich countries for damages for the greenhouse gases they've emitted.

Scientists in Belize believe their case is strong. They say the 297km (185 mile) reef here has suffered more than 40% damage since 1998.

They particularly implicate three events of coral bleaching when water temperatures were high.

Corals get their colour from tiny single-cell plants - zooxanthellae - which provide for the reef-building creatures, the polyps.

When temperatures are very high for a protracted period, the zooxanthellae are driven away, the coral loses its colour, the polyps lose their food and so the reef is weakened.

The reefs then easily fall victim to the many forces that assail them - over-fishing, pollution, creatures that eat them, tourist snorkellers who inadvertently smother them with sand, and particularly the storm waves of hurricanes.

Local fishermen say there is no record of bleaching before 1998.

Reef at forefront of CO2 battle