World's Corals facing 2nd biggest global die-off



World's coral faces second mass die-off

Scientists fear situation could be worse than '98, when 16 percent of coral was lost


Great Barrier Reef Park / AFP - Getty Images file
Some scientists fear the Great Barrier Reef, a bleached section of which is seen here in April 2009, will sustain further damage this year as part of a worldwide trend.

updated 9/21/2010 5:19:20 AM ET
This year’s extreme heat is putting the world’s coral reefs under such severe stress that scientists fear widespread die-offs, endangering not only the richest ecosystems in the ocean but also fisheries that feed millions of people.
From Thailand to Texas, corals are reacting to the heat stress by bleaching, or shedding their color and going into survival mode.
Many have already died, and more are expected to do so in coming months. Computer forecasts of water temperature suggest that corals in the Caribbean may undergo drastic bleaching in the next few weeks.
What is unfolding this year is only the second known global bleaching of coral reefs. Scientists are holding out hope that this year will not be as bad, over all, as 1998, the hottest year in the historical record, when an estimated 16 percent of the world’s shallow-water reefs died.
But in some places, including Thailand, the situation is looking worse than in 1998.
Scientists say the trouble with the reefs is linked to climate change.
'Significantly depressed'
For years they have warned that corals, highly sensitive to excess heat, would serve as an early indicator of the ecological distress on the planet caused by the buildup of greenhouse gases.
“I am significantly depressed by the whole situation,” said Clive Wilkinson, director of the Global Coral Reef Monitoring Network, an organization in Australia that is tracking this year’s disaster.
According to the National Oceanic and Atmospheric Administration, the first eight months of 2010 matched 1998 as the hottest January to August period on record.
High ocean temperatures are taxing the organisms most sensitive to them, the shallow-water corals that create some of the world’s most vibrant and colorful seascapes.
Coral reefs occupy a tiny fraction of the ocean, but they harbor perhaps a quarter of all marine species, including a profusion of fish.
Often called the rain forests of the sea, they are the foundation not only of important fishing industries but also of tourist economies worth billions.
Drastic die-offs of coral were seen for the first time in 1983 in the eastern Pacific and the Caribbean, during a large-scale weather event known as El Niño.
During an El Niño, warm waters normally confined to the western Pacific flow to the east; 2010 is also an El Niño year.
Serious regional bleaching has occurred intermittently since the 1983 disaster. It is clear that natural weather variability plays a role in overheating the reefs, but scientists say it cannot, by itself, explain what has become a recurring phenomenon.
“It is a lot easier for oceans to heat up above the corals’ thresholds for bleaching when climate change is warming the baseline temperatures,” said C. Mark Eakin, who runs a program called Coral Reef Watch for the National Oceanic and Atmospheric Administration. “If you get an event like El Niño or you just get a hot summer, it’s going to be on top of the warmest temperatures we’ve ever seen.”
Brilliant colors
Coral reefs are made up of millions of tiny animals, called polyps, that form symbiotic relationships with algae. The polyps essentially act as farmers, supplying the algae with nutrients and a place to live. The algae in turn capture sunlight and carbon dioxide to make sugars that feed the coral polyps.
The captive algae give reefs their brilliant colors. Many reef fish sport fantastical colors and patterns themselves, as though dressing to match their surroundings.
Coral bleaching occurs when high heat and bright sunshine cause the metabolism of the algae to speed out of control, and they start creating toxins. The polyps essentially recoil. “The algae are spat out,” Dr. Wilkinson said.
The corals look white afterward, as though they have been bleached. If temperatures drop, the corals’ few remaining algae can reproduce and help the polyps recover. But corals are vulnerable to disease in their denuded condition, and if the heat stress continues, the corals starve to death.
Even on dead reefs, new coral polyps will often take hold, though the overall ecology of the reef may be permanently altered. The worst case is that a reef dies and never recovers.
In dozens of small island nations and on some coasts of Indonesia and the Philippines, people rely heavily on reef fish for food.
When corals die, the fish are not immediately doomed, but if the coral polyps do not recover, the reef can eventually collapse, scientists say, leaving the fishery far less productive.
Research shows that is already happening in parts of the Caribbean, though people there are not as dependent on fishing as those living on Pacific islands.
It will be months before this year’s toll is known for sure. But scientists tracking the fate of corals say they have already seen widespread bleaching in Southeast Asia and the western Pacific, with corals in Thailand, parts of Indonesia and some smaller island nations being hit especially hard earlier this year.
Signs of hope
Temperatures have since cooled in the western Pacific, and the immediate crisis has passed there, even as it accelerates in places like the Caribbean, where the waters are still warming. Serious bleaching has been seen recently in the Flower Garden Banks, a marine sanctuary off the Texas-Louisiana border.
In Thailand, “there some signs of recovery in places,” said James True, a biologist at Prince of Songkla University. But in other spots, he said, corals were hit so hard that it was not clear young polyps would be available from nearby areas to repopulate dead reefs.
“The concern we have now is that the bleaching is so widespread that potential source reefs upstream have been affected,” Dr. True said.
Even in a hot year, of course, climate varies considerably from place to place. The water temperatures in the Florida Keys are only slightly above normal this year, and the beloved reefs of that region have so far escaped serious harm.
Parts of the northern Caribbean, including the United States Virgin Islands, saw incipient bleaching this summer, but the tropical storms and hurricanes moving through the Atlantic have cooled the water there and may have saved some corals.
Farther south, though, temperatures are still remarkably high, putting many Caribbean reefs at risk.
Summer is only just beginning in the Southern Hemisphere, but water temperatures off Australia are also above normal, and some scientists are worried about the single most impressive reef on earth. The best hope now, Dr. Wilkinson said, is for mild tropical storms that would help to cool Australian waters.
“If we get a poor monsoon season,” he said, “I think we’re in for a serious bleaching on the Great Barrier Reef.”
This article, headlined " Extreme Heat Bleaches Coral, and Threat Is Seen," was first published in The New York Times.


I don't know if I believe so much in this global warming thing.... If your really look we are having the almost exact same temperature trends as we did in the 30s... Its just hills and valleys and what about last years winter being one of the coldest on records.... I think the world is getting warmer and the major industry's need to find cleaner/more efficient ways of doing things but i don't think that its as dooms day as people make it out to be.


Active Member
Originally Posted by fishhunter http:///forum/thread/380483/world-s-corals-facing-2nd-biggest-global-die-off#post_3320343
I don't know if I believe so much in this global warming thing.... If your really look we are having the almost exact same temperature trends as we did in the 30s... Its just hills and valleys and what about last years winter being one of the coldest on records.... I think the world is getting warmer and the major industry's need to find cleaner/more efficient ways of doing things but i don't think that its as dooms day as people make it out to be.
The problem is two fold. First, is that we simply don't know. There is a finite amount of 'things' we can test for/monitor, and this is where those of us that don't like ideas shoved down our throats start not to believe, is how certain people go about linking them. We know what temperature it is now, what temp is was last year, a hundred years ago, we think we know how hot it was 1000 years ago. We know about how much CO2 is in the atmosphere, and we think we can determine the different sources from the CO2. But the problem arises when they use estimates, to make estimations for these doomsday scenarios. We have no idea exactly how much fossil fuel is in the ground. We're finding new drill sites and patches of oil all the time. Yet in calculations used to determine carbon amounts for the planet, they use some arbitrary number (well, they put some research into it) of fossil fuels, then make estimations what the Earth can handle. How much carbon the Earth has, how much CO2 man consumes, and percentages of each.
Second, and perhaps the even larger issue, is the politics/policies behind it. The fact that 'they' think 'they' should be allowed to tax any product or company, any amount that 'they' feel, in the name of "protecting the environment," is absolutely nuts, and very scary. If things didn't seem so politically motivated, and perhaps a smarter, more researched, when we have all the facts route was taken, perhaps more people would be supportive. People who even believe most things science, and are generally pro-environment (like myself).
Not simply having two graphs lined up, one an annual global temperature chart, and a rising manmade CO2 emission chart, and say "See! See! There has to be a connection!!"

Do that, and it tends to make us not believe very strongly.


Active Member
The article mentions 1998 being the hottest year on record.
If I remember right, there was a volcano in 97 that erupted producing more gasses than the entire human species does in 12 years.
Sux :(