Scientists contributing to the TEEB process indicate that irreversible damage to coral reefs can occur at atmospheric CO2 concentrations of over 350 parts per million (ppm). This is linked with rising temperatures but also ocean acidification. Concentrations are already above this threshold and rising. It raises concerns that stabilizing CO2 levels at 450 ppm, or some 16 per cent above the current levels, may condemn this critical, multi-billion dollar ecosystem to extinction and take with it the livelihoods of 500 million people within a matter of decades.
Pavan Sukhdev, TEEB's study leader who is on secondment from Deutsche Bank, said the loss of the world's coral reefs would undermine one of nature's most productive assets and one that has a key role to play in coastal defense against a predicted rise in storm surges and other extreme weather events due to global warming.
"The ecosystem services from coral reefs - ranging from coastal defense to fish nurseries - are worth up to USD$170 billion annually; an estimated half a billion people depend on them for livelihoods and more than a quarter of all marine fish species are dependent on coral reefs".
"The climate stabilization goals of many governments may prove sufficient for some ecosystems and some biodiversity but there is now a real question mark against the survival of coral reefs world-wide and their natural treasure troves," he added.
"The economic consequences are significant, but so are the social and humanitarian ones. It underlines that a simple cost-benefit analysis alone will fail to capture the ethical dimensions of international climate policy decisions now and in the coming years and decades -especially in respect to an ecosystem at a climatic tipping point," said Mr Sukhdev, who also heads up the Green Economy initiative of the UN Environment Programme.
Mr Gabriel sa
|Contact: Tilo Arnhold|
Helmholtz Association of German Research Centres