"Global coral bleaching event that has lasted three YEARS has finally ended - but reefs are still fighting for their lives"

Nonsense all round.  The Indian ocean was not affected so the event was not global.  And it is admitted below that the effect was largely due to El Nino, not anthropogenic global warming.  They say that El Nino and anthropogenic global warming together had an additive effect but -- even conceding that CO2 causes anthropogenic global warming -- there was no CO2 rise in the relevant years so there was clearly NO rise in anthropogenic global warming.  To put it semi-algebraically:  El Nino + 0 = El Nino. 

And corals are at their most diverse and abundant in warm tropical waters so the claim that warm waters are bad for them is fundamentally perverse.  In Australia's case a sea-level fall was almost certainly the cause of bleaching in warm tropical water off the Far North Queensland coast

And both the extent of the loss and the difficulty of the recovery have been greatly exaggerated.  Do I need once again to mention the coral reef at Bikini atoll which was once the target of a thermonuclear blast -- but which is now again thriving?

 It's just all baseless assertion below.  Correlation is asserted as causation.  Factors like sea-level fluctuations are almost certainly involved but no attempt is made even to look at that.  One doesn't look to Warmists for a balanced account of anything -- which reveals them as fundamentally unscientific.  A scientific paper will normally look at all the possible causes of an event and evaluate them against one another. Warmists know just one cause for everything, ignore all else and assert it "ad infinitum"


A mass bleaching of coral reefs worldwide has finally ended after three years, U.S. scientists announced Monday.

About three-quarters of the world's delicate coral reefs were damaged or killed by hot water in what scientists say was the largest coral catastrophe.

The National Oceanic and Atmospheric Administration first announced a global bleaching event in May 2014.

It was worse than previous global bleaching events in 1998 and 2010.

The forecast damage doesn't look widespread in the Indian Ocean, so the event loses its global scope.

Bleaching will still be bad in the Caribbean and Pacific, but it'll be less severe than recent years, said NOAA coral reef watch coordinator C. Mark Eakin.

Places like Australia's Great Barrier Reef, northwest Hawaii, Guam and parts of the Caribbean have been hit with back-to-back-to-back destruction, Eakin said.

University of Victoria, British Columbia, coral reef scientist Julia Baum plans to travel to Christmas Island in the Pacific where the coral reefs have looked like ghost towns in recent years.

While conditions are improving, it's too early to celebrate, said Eakin, adding that the world may be at a new normal where reefs are barely able to survive during good conditions.

Eakin said coral have difficulty surviving water already getting warmer by man-made climate change. Extra heating of the water from a natural El Nino nudges coral conditions over the edge.

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Why did physicist Dr. Ridd conclude that corals thrive in warmer water and will flourish as global warming increases?

The above question appeared on Quora and the responses are instructive.  The first commenter, Hirsekorn, started out with an incorrect "ad hominem" assertion about Dr. Ridd's academic background.  I quote from Ridd's page at his university: 

"Peter Ridd is a geophysicist with the following interests: coastal oceanography, the effects of sediments on coral reefs, instrument development, geophysical sensing of the earth, past and future climates, atmospheric modelling. In addition with his group in the Marine Geophysics Laboratory "

So Dr. Ridd's background leaves him amply qualified to speak on reef problems.

The next point made by the same author, Hirsekorn, is that individual corals differ in the optimal temperature of the waters surrounding them.  That is undoubtedly true but it offers no scale for that effect.  The acceptable range of temperature could be large and it could differ for individual corals.  And in fact it does, as we see here

So the comments by Hirsekorn have no merit whatever and, as such, are of the standard we have come to expect from Warmists defending their addled theory.

The second comment, by Reiner, is well informed, extensive and perfectly correct.  In particular, it has now been shown that sea level variations in recent times have been the major cause of coral bleaching.  I was unaware that Peter Ridd had predicted that some years back so he is revealed as a good scientist:  One whose theories are borne out by reality

The two original Quora comments below:


Answer by Alex Hirsekorn, lifetime seashore aficionado:

Assuming that you’re referring to Prof. Peter Ridd of James Cook Univ. I would guess that he reached such a conclusion because he is not a biologist but a geophysicist that apparently doesn’t talk to biologists very much.

There are something like 1,000 species of "reef building" coral worldwide and if you plot them by geographic location versus species you will see that they have definite preferences regarding temperature. Looking a bit more carefully will demonstrate that any given species’ numbers will diminish as you leave its temperature ‘sweet spot’ for waters that are either colder or warmer.

You don’t need to be a professor to understand this concept. I’m willing to give the benefit of the doubt and say he was probably misquoted; the alternative explanation is that he’s either a moron or willfully ignorant.


Comment by Bryson Reiner, studied at PhD in Biochemistry:

Peter Ridd is a marine physicist and has published multiple studies on sediments and their effect on coral reefs. Having spoken with Dr Ridd, my understanding is that he was suggesting corals do well not directly due to increased temps-but rather due to increased sea levels. From what I can recall, and my memory is admittedly foggy on this as it was over 5 years ago, that the Great Barrier Reef along the Queensland coast has suffered from declining sea levels which destroys coral. I am pretty sure he was inferring that rising sea levels as a result of a warming trend would increase coral growth-not as a direct result of temperature increase.

To professor Ridd’s credit, he is a strong advocate for reproducibility in the marine sciences and decries sensationalism in science. In particular he mentioned the inability to reproduce studies indicating changes in ocean pH as huge shifts in pH occurred with upwelling and even recent rains which caused short term changes but the studies results were not reproducible over long term. As an aside, certain corals will die in cooler temps just as some may die in warmer temps.

Empirically, as an avid diver-I can attest to the fact that inshore reefs are very likely affected by run off. I've been diving at an unusually inshore reef with huge coral mounts not 20 m from shore since the early 80s which was almost inaccessible as it was on the side of a small mountain in the carribean with only 3 houses nearby and a sheer dirt road that was often washed out. The reef was healthy and vibrant until 2013 when a high end housing development went up complete with a paved road. The effect was immediate as the reef went from vibrant reds, yellows, greens and blues to dull gray. The coral closest to shore was the most affected with another swath of graying coral that went well out to 100 m from shore which I couldn't quite figure out until I saw it rain which produced a huge outflow that ran along a rock jetty as a current which ran identical to the swath of dead coral. The coral has become progressively grey with each visit being worse than the last although the most affected areas remain the ones described. Yes, pollution in petroleum products and detergents certainly have an effect on coral-but to suggest that all, or even most instances of coral bleaching are due solely to temperature change is likely not the case and has yet to be determined at best.

Additionally, there are thriving corals that survive with dramatic changes in temperature near and in the Atlantic gulfstream which shifts its location by tens of miles regularly with temperature changes greater than 20 F-it's a literal column of water where within 10 meters you'll have a 60 F reading and a 80 temp. These corals are still healthy and vivid in color with life teeming all round and withstand these temperature changes on a regular and frequent basis. To suggest less than 1 C degree of change is wiping out corals is likely an overstatement.

I'm a firm believer that coral should be protected as they serve as oceanic estuaries and are simply beautiful little wonders to observe. But I suspect we'll get much better results by investing resources in controlling run off and spills rather than trying to manage the global climate. Specific efforts targeted directly at saving our reefs and coral seem more feasible in this instance vs macromanaging daunting things like the climate which in this instance is inconclusive in the degree to which it may affect the viability of coral. I'll go a step further and guess that managing directly runoff and spills will have a more immediate and dramatic effect on coral health and sustainability than even a successful attempt to change global climate.

SOURCE

‘Super Corals’ Are Resilient To Climate Change, Scientists Discover

Scientists have discovered a population of “super corals” that appear to have become resistant to extreme environmental conditions — being able to survive and thrive in hot, acidic and low-oxygen waters. And they now plan to search for more climate-adaptable coral populations within the Great Barrier Reef.

An international team of researchers first found the super corals during an expedition to a remote lagoon in New Caledonia in 2016. Their “surprising results” showed the lagoon had a diverse community of reef-building corals that had adapted to live in extreme these conditions.

Publishing their findings in the journal Scientific Reports, the team was investigating coral reef health in relating to climate change. As oceans get warmer and more acidic, vast swathes of coral species suffer. This has been documented globally, with a recent report from the Australian Research Council showing two thirds of the Great Barrier Reef had been affected so far this year.

Coral bleaching occurs when waters are too warm. These conditions make the corals expel the algae living in their tissues—causing them to lose their color. Algae provides coral with 90 percent of its energy, so while this process does not kill it, it places the coral under far greater stress and puts it at greater risk of death.

As global temperatures increase, scientists are increasingly concerned about how coral reefs—which form barriers protecting shorelines from waves and storms, and provide ecosystems for a vast number of species—will fare.

The latest findings provide some relief. Emma Camp, from the University of Technology Sydney (UTS), Australia, and colleagues found water in the semi-enclosed lagoon system was hot, acidic and lacking in oxygen when compared to neighboring reefs. Yet its coral communities was surprisingly rich—there were 20 species covering up to 35 percent of the lagoon site.

“Enhanced coral respiration, alongside high particulate organic content of the lagoon sediment, suggests acclimatisation to this trio of temperature, oxygen and pH changes through heterotrophic plasticity.” Heterotrophic refers to organisms that depend on organic substances for nutrients because they cannot make their own food.

In a statement, Camp said: “The existence of corals living under this usually deadly trio of conditions, comparable and even exceeding what is predicted under climate change, gives us new hope that some corals will be able to persist into the future. These could indeed be the super corals of the future that will help support proactive management options attempting to upgrade reef resilience.”

Concluding, the team wrote: “Evidence here, and from other similar habitats increasingly highlight that reef neighboring systems could act as local reservoirs of coral populations highly resistant to extreme environmental conditions.”

The next step in their research is to search for similar systems in the Great Barrier Reef. The expedition, funded by the National Geographic Society Waitt Foundation, will allow the team to explore mangrove systems—which have similar, extreme conditions to those seen in New Caledonia—and how corals there may have adapted.

“As a result of the expedition we will be able to collect invaluable baseline physical and molecular data to discover how corals within the Great Barrier Reef have already adapted and how they might cope in the future,” Camp said. “I’m excited at the prospect of being able to transfer our discoveries from other sites to our own home reefs.”

David Suggett, who will accompany Camp on the expedition, said: “By exploring the very margins—such as reef-neighbouring mangroves that are often ignored by coral surveys—we’re continually finding populations of super coral that are resistant to hot, acidic and hypoxic conditions predicted under climate change. This is a game changer for how we consider coral reef resilience into the future for the Great Barrier Reef.

SOURCE