by Magnifico
Thu Sep 3rd, 2009 at 03:50:38 AM EST
We are killing the world's coral reefs and their situation is virtually hopeless.
"The future is horrific," says Charlie Veron, an Australian marine biologist who is widely regarded as the world's foremost expert on coral reefs.
"There is no hope of reefs surviving to even mid-century in any form that we now recognise. If, and when, they go, they will take with them about one-third of the world's marine biodiversity. Then there is a domino effect, as reefs fail so will other ecosystems. This is the path of a mass extinction event, when most life, especially tropical marine life, goes extinct."
Or, as David Adam explains in his Guardian article about Why coral reefs face a catastrophic future:
Within just a few decades, experts are warning, the tropical reefs strung around the middle of our planet like a jewelled corset will reduce to rubble. Giant piles of slime-covered rubbish will litter the sea bed and spell in large distressing letters for the rest of foreseeable time: Humans Were Here.
They are not alone in their bleak outlook for the future of the world's coral reefs.
The Telegraph reported yesterday that the Great Barrier Reef facing 'catastrophic damage' from climate change. The Great Barrier Reef Marine Park Authority in Australia has published its Outlook Report 2009 on the state of the reef's health. It's not good -- coastal runoff, polluted water, development, and illegal fishing are the immediate threats to the reef.
"Even with the recent management initiatives to improve resilience, the overall outlook for the Great Barrier Reef is poor and catastrophic damage to the ecosystem may not be averted," the report found.
"If changes in the world's climate become too severe, no management actions will be able to climate-proof" its ecosystem, it said.
The Age reports that the Great Barrier Reef survival chances are poor even with moderate climate change.
"Eminent marine researcher and former chief scientist of the Australian Institute of Marine Science Charlie Veron, who helped prepare the report," said the carbon target (450 ppm) supported by Australia's government, "would result in the complete death of the reef by 2050."
Prime Minister Kevin ''Rudd would not be supporting the 450 target if he knew the facts,'' Veron said. ''This isn't a theory - all the science is incredibly concrete now and it is backed by everybody in the coral research field.''
The Sydney Morning Herald noted the Australian government says "the reef contributes about $5.4 billion to the Australian economy through tourism, fishing and other industries and supports more than 50,000 jobs".
The Great Barrier Reef isn't the only reef threatened. The Guardian article notes:
Alex Rogers, a coral expert with the Zoological Society of London, talks of an "absolute guarantee of their annihilation".
And David Obura, another coral heavyweight and head of CORDIO East Africa, a research group in Kenya, is equally pessimistic: "I don't think reefs have much of a chance. And what's happening to reefs is a parable of what is going to happen to everything else."
"These are desperate words," writes Adam, "stripped of the usual scientific caveats and expressions of uncertainty, and they are a measure of the enormity of what's happening to our reefs."
Rivers polluted with agricultural nutrients nitrates and phosphates, mixed with sediment and sewage are "enough to wreck coral without any help from climate change", but climate change is dealing coral its death blow in two parts.
First, is the warming oceans. In 2005, Mongabay reported that the projected 1.5° Celsius increase in ocean temperatures that is expected by climate scientists will wipe out 95% of the living coral in the Great Barrier Reef by 2050. According to Ove Hoegh-Guldberg, head of the University of Queensland's Centre for Marine Studies, is "higher sea temperatures that cause thermal stress for corals."
Second, is ocean acidification. "Beyond 500 ppm coral reefs may no longer exist. Much of the Pacific Ocean will likely be marginal for coral reefs while net calcification rates will be approaching zero," Hoegh-Guldberg said.
Carbon dioxide from burning fossil fuels pollutes the atmosphere and then, in part, is absorbed by the world's oceans. Adam of The Guardian writes:
While mankind has squabbled, delayed, distracted and dithered over the impact that carbon emissions have on the atmosphere, that dissolved pollution has been steadily turning the oceans more acidic. There is no dispute, no denial, about this one. Chemistry is chemistry, and carbon dioxide plus water has made carbonic acid since the dawn of time.
As a result, the surface waters of the world's oceans have dropped by about 0.1 pH unit - a sentence that proves the hopeless inadequacy of scientific terminology to express certain concepts. It sounds small, but is a truly jaw-dropping change for coral reefs.
While coral reforestation efforts could help restore damaged coral, coral still needs the calcium mineral aragonite in the seawater to form their skeletons. As the oceans grow more acidic, coral does not even have a fighting chance of making a comeback.
"Rogers says carbon dioxide levels in the atmosphere are already over the safe limits for coral reefs" and unless we can remove carbon from the air more of it will be absorbed by the world's oceans and dissolve the coral reefs.
"I just don't see the world having the commitment to sort this one out," says Obura. "We need to use the coral reef lesson to wake us up and not let this happen to a hundred other ecosystems."
The coral community isn't optimistic we'll reduce carbon emissions in time. And you know? They're probably right. Go ahead and add coral reefs to the doom tourism itinerary. Take some pictures for future generations. How about a before and after type image courtesy of NOAA?
Cross-posted from Daily Kos.
