NOAA is dialing back the alarm a bit with realizations that nature has equipped these organisms with adaptation strategies that have served them over the millennia.
New study suggests coral reefs may be able to adapt to moderate climate change
Coral reefs may be able to adapt to moderate climate warming, improving their chance of surviving through the end of this century, if there are large reductions in carbon dioxide emissions, according to a study funded by NOAA and researched by the agency’s scientists and its academic partners. Results further suggest corals have already adapted to part of the warming that has occurred.
“Earlier modeling work suggested that coral reefs would be gone by the middle of this century. Our study shows that if corals can adapt to warming that has occurred over the past 40 to 60 years, some coral reefs may persist through the end of this century,” said study lead author Cheryl Logan, Ph.D., an assistant professor in California State University Monterey Bay’s Division of Science and Environmental Policy. The scientists from the university, and from the University of British Columbia, were NOAA’s partners in the study.
Warm water can contribute to a potentially fatal process known as coral “bleaching,” in which reef-building corals eject algae living inside their tissues. Corals bleach when oceans warm only 1-2°C (2-4°F) above normal summertime temperatures. Because those algae supply the coral with most of its food, prolonged bleaching and associated disease often kills corals.
The study, published online in the journal Global Change Biology, explores a range of possible coral adaptive responses to thermal stress previously identified by the scientific community. It suggests that coral reefs may be more resilient than previously thought due to past studies that did not consider effects of possible adaptation.
The study projected that, through genetic adaptation, the reefs could reduce the currently projected rate of temperature-induced bleaching by 20 to 80 percent of levels expected by the year 2100, if there are large reductions in carbon dioxide emissions.
“The hope this work brings is only achieved if there is significant reduction of human-related emissions of heat-trapping gases,” said Mark Eakin, Ph.D., who serves as director of the NOAA Coral Reef Watch monitoring program, which tracks bleaching events worldwide. “Adaptation provides no significant slowing in the loss of coral reefs if we continue to increase our rate of fossil fuel use.”
“Not all species will be able to adapt fast enough or to the same extent, so coral communities will look and function differently than they do today,” CalState’s Logan said.
While this paper focuses on ocean warming, many other general threats to coral species have been documented to exist that affect their long-term survival, such as coral disease, acidification, and sedimentation. Other threats to corals are sea-level rise, pollution, storm damage, destructive fishing practices, and direct harvest for ornamental trade.
According to the Status of Coral Reefs of the World: 2000 report, coral reefs have been lost around the world in recent decades with almost 20 percent of reefs lost globally to high temperatures during the 1998-1999 El Niño and La Niña and an 80 percent percent loss of coral cover in the Caribbean was documented in a 2003 Science paper. Both rates of decline have subsequently been documented in numerous other studies as an on-going trend.
Tropical coral reef ecosystems are among the most diverse ecosystems in the world, and provide economic and social stability to many nations in the form of food security, where reef fish provide both food and fishing jobs, and economic revenue from tourism. Mass coral bleaching and reef death has increased around the world over the past three decades, raising questions about the future of coral reef ecosystems.
In the study, researchers used global sea surface temperature output from the NOAA/GFDL Earth System Model-2 for the pre-industrial period though 2100 to project rates of coral bleaching.
Because initial results showed that past temperature increases should have bleached reefs more often than has actually occurred, researchers looked into ways that corals may be able to adapt to warming and delay the bleaching process.
The article calls for further research to test the rate and limit of different adaptive responses for coral species across latitudes and ocean basins to determine if, and how much, corals can actually respond to increasing thermal stress.
In addition to Logan, the other authors of the paper were John Dunne, NOAA Geophysical Fluid Dynamics Laboratory; Eakin, NOAA’s Coral Reef Watch; and Simon Donner, Department of Geography at the University of British Columbia. NOAA’s Coral Reef Conservation Program funded the study.
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This should come as no surprise, since they adapted so well during all those previous centuries & millennia during which the oceans were much warmer than now, not to mention tens & hundreds of thousands & millions of years.
I’m confused now – is it “worse than we thought” or “not worse than we thought”?
Obviously I see they suggest more grants/ research is required to ascertain the right answer!
This could run and run.
The phrase “NO SH1T, SHERLOCK” comes to mind…
They are just shocked that the model output didn’t fit reality, so what are they claiming? Reality must be doing something we are unaware of, because the models we have built CAN’T be wrong!
OH yeah, we need more money.
So reefs have adapted in the past but can now only adapt if we stop emitting CO2.
As the rate of rise in temperature is indistinguishable from before the industrial release of CO2 this must be due to acidification, not temperature stress.
Yet the pH change is also theoretical not empirical.
This raises the question of what is the point of the NOAA Coral Reef Watch monitoring program.
It doesn’t seem to be monitoring so much as guessing.
What warming?
An organism that has survived millions of years of climate change is discovered to have the ability to adapt to changing temperatures. Color me shocked!
But this is impossible, the coral reefs went extinct with the polar bears in each of the last 5 warming periods.
IPCC TM science-y stuff.
So coral reefs that survived the roman warm period, the medieval warm period and the little ice age can survive “moderate climate change”? Amazing!
Well NOAA can try being moderate all they like, but it is far, far too late for that. They allowed Tom Karls pet rat TOBy to chew on surface station data. Their hands will never be clean.
It is rather simple: There are place in the ocean too cold, too turbid, too saline for coral, but there are no places where the lack of coral is due solely to temperature. There is a reason the greatest coral diversity lies near the equator.
Coral bleaching again… “If I stop blushing, I’ll die.” For those that keep coral in aquariums this has been long known and understood. Corals don’t have color as such. All their majesty comes from a symbiotic relationship with algae, zooxanthellae. And the corals regulate their energy production by… expelling zooxanthellae when things are too active. eg. Bleaching is what gets done when the coral is gluttonous and want to go on a diet.
And this is on the surface, but down under ( not Australia )
http://www.treasure-island-shipping.com
they just may supply the answers to the questions that many are asking
For most of their history, corals have lived happily & built reefs in much warmer seas than now & under much higher CO2 concentrations. They also survived the second & third biggest mass extinction events of the Phanerozoic, the Triassic-Jurassic & Cretaceous-Tertiary, plus possibly even the Mother of All MEEs, the Permian-Triassic. Can’t be sure about the latter, since corals don’t definitely show up until the Triassic.
http://coral.aims.gov.au/info/evolution.jsp
Mark and two Cats says:
October 29, 2013 at 12:30 pm
The phrase “NO SH1T, SHERLOCK” comes to mind…
*
Mark and two Cats says it for me.
Can we please stop funding these stupid reports now? We KNOW nature adapts. We don’t need more money down the drain to tell us what we already know linked to more doomsday prophecy tipping point lies if we don’t change our lifestyles.
“Mass coral bleaching and reef death has increased around the world over the past three decades, raising questions about the future of coral reef ecosystems.” Oh yeah? Really? Mass bleaching and reef death? Really? As though coral doesn’t like warm water. Sheesh!
Pull. The. Plug.
its not only heat that corals are susceptible to. a few years ago there was a big coral die-off off of the FL coast when a very strong cold front went through. does anyone know if those were able to recover?
It seems like their latest study is why the peer reviewers ought to rejected the earlier claims of coral reefs dying mid century. Funny how they end up with 2 published papers out of it! No common sense on display at all.
Marcos says:
October 29, 2013 at 1:09 pm
Dunno about recovery yet, but distinct species are affected differently:
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2011.02487.x/abstract
Bear in mind that the impressive Florida Reefs (third largest barrier coral reef system on the planet) are only five to seven thousand years old, having developed in the Holocene interglacial.
Jquip on October 29, 2013 at 12:57 pm
Well said. There’s an old line that a dog doesn’t s..t where it eats. A coral is near the base of evolution: its mouth is its anus. And it’s more or less fixed in place. So it does s..t where it eats: a potentially toxic combination. As you stated, the symbiotic algae within the coral is what give it its color. The algae consumes the waste products from the coral – to the benefit of the algae. The consumption of the coral’s waste products by the algae keeps the coral’s environment clean – to the benefit of the coral. However, over time the waste products, and possibly metals, build up within the algae to the point where a sudden die-off would prove fatal to its host coral. It’s been theorized that corals, which have existed far closer to the beginning of life than we have, will routinely ‘bleach’ (shed the algae) as an insurance policy against this.
I’m so tired of hearing these ‘experts’ reduce everything, everywhere, every time, in every circumstance ever imaginable to nothing else ever than a function of nothing other than temperature. How extraordinarily simplistic, uncreative, and intellectual lazy. Oh, and indicative of an immature desire for group acceptance.
Coral flourishes in shallow, clear, clean and WARM marine waters where a healthy predator specie population can keep the coral grazers in check. Never in the warmists lamenting about the loss of coral do they address the real and rather simple adverse impacts to coralline health…increased sediment and refined chemical load, and overfishing. Human caused? In most cases, yes. From CO2 and resultant “acidification”, no!
“…almost 20 percent of reefs lost globally to high temperatures during the 1998-1999 El Niño and La Niña…”
And then the corals grew back again after the brief spike in temperatures from the major El Niño and La Niña events subsided. That part always seems to be left out of these reports. I wonder why?
The Wikipedia article on coral bleaching mentions that Great Barrier Reef experienced up to 90% mortality of corals in some places: “However coral losses on the reef between 1995 and 2009 were largely offset by growth of new corals. An overall analysis of coral loss found that coral populations on the Great Barrier Reef had declined by 50.7% from 1985 to 2012, but with only about 10% of that decline attributable to bleaching, and the remaining 90% caused about equally by tropical cyclones and by predation by crown-of-thorns starfishes.”
But we never hear about the fact that corals grow back or that temperature change (warming AND cooling) is only one of many possible causes. “Possible causes” meaning that drastic temperature changes don’t appear to affect some corals; so it’s not clear what’s actually going on.
Another thing that seems to be ignored is that ocean temperature changes that have affected corals happen relatively rapidly and are caused by ocean circulation, not by increases in air temperature. There is no evidence that the very modest air temperature increases over a comparatively long time period (decades) predicted by the IPCC would affect corals at all.
The good news is that this only affects coral living between 700 meters to 2000 meters, where the actual warming is hiding.
The other thing they ignore is that most coral grows in cyclone/typhoon/hurricane-prone areas. You should see what happens when a big one comes through. The coral (and everything else) gets utterly trashed and covered in muck.
Guess what? A few years later, it’s grown back. Fragile system, what a load of the proverbial.
These people are idiots.
Apparently these so called NOAA coral researchers never read any of the science literature relevant to their research.
They don’t seem to know that the research has already been done on the coral’s aquatic algae partner’s ability to adapt to different water conditions including temperature changes simply by a small change in the variety of algae which enables the coral to adapt to changes in water conditions.
Quoted from the Science Daily site of April 11th 2012.
http://www.sciencedaily.com/releases/2012/04/120411084131.htm
[quote]
Widespread Adaptability: Coral Reefs May Be Able to Adapt to Climate Change With Help from Algae
A new study by scientists at the University of Miami’s Rosenstiel School of Marine & Atmospheric Science suggests that many species of reef-building corals may be able to adapt to warming waters by relying on their closest aquatic partners — algae. The corals’ ability to host a variety of algal types, each with different sensitivities to environmental stress, could offer a much-needed lifeline in the face of global climate change.
Using a highly sensitive genetic technique, Ph.D. student Rachel Silverstein analyzed 39 coral species from DNA collected in the Indo-Pacific and Caribbean collected over the last 15 years. Most of these species had not previously been thought capable of hosting more than one type of the single-celled symbiotic algae, called zooxanthellae, which live inside the coral and help to supply them with energy.
Silverstein’s results revealed that at least one colony of all 39 species tested had at least two varieties of algae, including one thought to be heat tolerant. Over half of the species were found to associate with all four of the major types of algae found in corals.
“This study shows that more coral species are able to host multiple algal symbionts than we previously thought,” said Andrew Baker, associate professor at UM’s Rosenstiel School and co-author of the study. “The fact that they all seem to be capable of hosting symbionts that might help them survive warmer temperatures suggests they have hidden potential that was once thought to be confined to just a few special species.”[ end quote]
NOAA; We have just invented a new device called the “wheel”
Please send more money as we think we can make it work better if we shave all the four corners off!