13/04/2016

Great Barrier Reef: Close-Up Pictures Show Stark Effects Of Coral Bleaching

ABC News - Justin Marshall*

These images are a selection of photos taken recently near Lizard Island off the North Queensland coast. They document the ongoing bleaching on the Great Barrier Reef as ocean temperatures continue to be driven upward by climate change.
Pink-tinged bleaching
Pink-tinged bleaching. (Justin Marshall/coralwatch.org)
The bleaching process
Before corals bleach, they are often a deep brown or khaki-green colour. These colours come from the symbiotic algae (sometimes called zooxanthellae) that co-exist with the coral polyp.
Coral before bleaching
Coral before bleaching. (Justin Marshall/coralwatch.org)
During bleaching, as the symbiotic algae depart, you can see the beautifully coloured polyps. Sometimes polyps are transparent and we see only the white skeleton beneath. Other polyps may be brightly coloured, as seen here.
Coral during bleaching
Coral during bleaching. (Justin Marshall/coralwatch.org)
But whether white or fluorescent, these corals are far from happy. Once the final stage of the bleaching process is reached, it is likely the coral has been stressed for days or weeks.
From here on, it may recover slowly — by re-acquiring its symbiont friends — or it may die, having run out of energy in the absence of the symbiotic algae that provide it with carbohydrates.
What often happens next is that the coral is covered with a film of turf algae, which takes over the parts of the reef previously colonised by healthy coral.
Coral after bleaching
Coral after bleaching. (Justin Marshall/coralwatch.org)
Bleaching can be strangely beautiful
Unfortunately, what we are now seeing on the northern third of the Great Barrier Reef is the death of many of these beautiful organisms. But, as noted above, the bleaching can in some cases be weirdly beautiful, as the corals shed their algal cloaks and reveal themselves.
Bleached corals
Bleached corals glow a striking shade of purple. (Justin Marshall/coralwatch.org)

These pictures show a variety of heavily bleached corals, with almost no remaining symbiotic algae. From this point it is a long, slow road to recovery — even those corals that survive will remain metabolically and reproductively compromised for months.
Purple-tinged bleaching
Purple-tinged bleaching. (Justin Marshall/coralwatch.org)

Pure white bleaching
Pure white bleaching. (Justin Marshall/coralwatch.org)
The amazing colours are pigments present in the coral polyps themselves.
They are often fluorescent — hence the day-glo appearance of some corals and their amazing fluorescence on torch-lit night dives.
Purple glow
Purple glow. (Justin Marshall/coralwatch.org)

Some healthy corals display such vivid blues and other colours naturally, not during a bleaching event. But these corals are rare.
What we are seeing on reefs in northern Queensland is certainly bleaching.
Blue tips
Blue tips. (Justin Marshall/coralwatch.org)

Bleached colonies
Bleached colonies stand out starkly. (Justin Marshall/coralwatch.org)
Algal overgrowth
When the polyps die, macro or turf algae take over — a process that is already evident along parts of the 800 kilometres of worst-affected Great Barrier Reef.
Non-symbiotic algae
Non-symbiotic algae begin to take hold. (Justin Marshall/coralwatch.org)
Especially in warm or nutrient-rich waters, these algae outcompete any coral trying to settle or spread on the reef, taking over areas that corals previously dominated.
Algae growing on coral tips
Algae growing on coral tips. (Justin Marshall/coralwatch.org)

Coral and algae
A mix of starkly bleached coral and algal colonisation. (Justin Marshall/coralwatch.org)
Fish losing their homes
Not only is the turf algal community uglier than healthy coral, but it means the other species that depend on the coral lose their livelihoods too. Eventually, the reef structure itself breaks down, meaning that many fish species will need to move on or die.
That includes fish that feed on coral, such as this Okinawa goby …
Okinawa goby
An Okinawa goby on a coral colony. (Justin Marshall/coralwatch.org)

… and those that just use it for shelter, such as this black damselfish juvenile.
Juvenile black damselfish
Juvenile black damselfish. (Justin Marshall/coralwatch.org)
The turquoise-blue chromis damselfish form huge clouds or schools over coral heads, and use coral branches for shelter when predators come along. The picture immediately below was taken before bleaching, while the one after that shows the fish on a bleached colony.
Fish on a healthy reef
Before: Chromis damselfish on a healthy reef. (Justin Marshall/coralwatch.org)

Fish on bleached coral
After: Chromis damselfish on bleached coral. (Justin Marshall/coralwatch.org)
Anemones (which are close relatives of corals) are also prone to bleaching, which causes similar problems for the fish that use them for shelter.
Here are some more before and after photos, showing the effects of bleaching on the anemones that species such as clownfish use as a refuge.
Anemones
Anemones are prone to bleaching too. (Justin Marshall/coralwatch.org)

Bleached anemone
After: Fish on a bleached anemone. (Justin Marshall/coralwatch.org)
Living with coral... or without it
When I saw the coral this perky little blenny is sitting in, I was convinced I was looking at a healthy colony! Maybe Lizard Island was not 100 per cent bleached after all.
Unfortunately, closer examination shows that the coral head has died and a thin film of algae covers the branches. The little blenny is farming his patch and cropping the algae so that it does not become overgrown.
A blenny on the reef
A blenny on the reef. (Justin Marshall/coralwatch.org)

Tending the algae
Tending the algae. (Justin Marshall/coralwatch.org)
One-third of all marine life spends at least part of its life cycle on a reef. What happens when these reefs disappear?
Current predictions are that coral reefs worldwide could be gone within 25 years. How much will be left after this global bleaching event? How much will be left for future generations?
Given the globally accepted link between carbon emissions, climate change and reef bleaching, the decision to approve the Carmichael coal mine in Queensland right next to the Great Barrier Reef really is adding insult to injury.
The continued loss of the Great Barrier Reef is an environmental tragedy and a huge blow to all Australians who cherish this natural wonder and to the tourists who flock here to see the reef — particularly after seeing David Attenborough's new documentary on it.
Further afield, coral bleaching is a potential humanitarian crisis in countries that rely on reefs for food and basic livelihoods. Let's not forget that when Australia burns or sells coal it is contributing to this global problem as well.

*Justin Marshall is an ARC Laureate Fellow and director of CoralWatch at The University of Queensland

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For James Hansen, the Science Demands Activism on Climate

Yale Environment 360Katherine Bagley*

Climate scientist James Hansen has crossed the classic divide between research and activism. In an interview with Yale Environment 360, he responds to critics and explains why he believes the reality of climate change requires him to speak out.
Climate scientist James Hansen. 'There's no way we can burn all that's available without guaranteeing that it's a completely different planet.' Photograph: Murdo MacLeod for the Guardian

Climate scientist James Hansen has been a prominent figure in the global climate conversation for more than 40 years.

His 1988 congressional testimony on climate change helped introduce the problem of rising greenhouse gas emissions to the American public, and he has led study after study examining exactly how our world will change as a result of global warming.

Eight years ago, however, Hansen made the rare decision to begin engaging in climate activism, and he has since protested mountaintop removal in West Virginia and gotten arrested outside the White House in a rally against the Keystone XL pipeline.

His actions have earned him both praise and criticism from the media and scientific community. Recent scientific endeavors of his — including a study last month that was publicized prior to being peer-reviewed — have also generated controversy.

In an interview with Yale Environment 360 last week, Hansen, former director of the NASA Goddard Institute for Space Studies in New York, opened up about his unconventional career path, his frustration watching policymakers' four decades of climate inaction, and what he believes the world could look like a century from now.

"I don't think that I have been alarmist — maybe alarming, but I don't think I'm an alarmist," he said. "We have a society in which most people have become unable to understand or appreciate science, and partly that's a communication problem, which we need to try to alleviate."

Yale Environment 360: In a paper released last month in the journal Atmospheric Chemistry and Physics Discussion, you and colleagues argued that 2 degrees Celsius of warming could be "dangerous," setting the stage for abrupt climatic changes. Can you describe more in detail what could happen under this scenario? What would the world look like?

James Hansen: We know from the earth's history that 2 degrees would eventually lead to sea level rise of several meters. The last inner glacial period, 120,000 years ago, that's the last time it was warmer than today, sea level was 6 to 9 meters higher — that would mean loss of almost all coastal cities. It's unthinkable that we walk into such a situation with our eyes open, and yet, the science is very well understood.

There's no argument about the fact that we will lose the coastal areas, now occupied by most of the large cities of the world. It's only a question of how soon. That message, I don't think, has been clearly brought to the policymakers and the public. More than 190 nations agreed [at the Paris climate conference last December] that we should avoid dangerous human-made climate change. That loss of coastal cities would be a dangerous outcome. It's hard to imagine that the world will be governable if this happened relatively rapidly.

What we conclude is that the timescale for ice-sheet disintegration is probably a lot shorter than has been assumed in the intergovernmental discussions.
What we could not have guessed is the fact that the world's governments would be so unresponsive to the increasing empirical evidence.
e360: You started researching climate change back in the 1970s. Forty years later, could you ever have imagined the scientific community would be predicting sea level rise of several meters?

Hansen: I could imagine that we would be predicting that, but I'm disappointed that policy actions have not been achieved to deal with it. The first major paper that we published on climate was in 1981 in Science magazine. It focused on the fact that if we kept burning fossil fuels, burn most of the fossil fuels, it would guarantee sea level rise of many meters. We also talked about the amount of warming we expected, when it would rise above the level of natural variability, and the fact that the Arctic would lose its sea ice — we would open the fabled Northwest Passage, and there would be a creation of drought-prone regions in North America and Asia.

I remember commenting to my co-author, [NASA scientist] Andy Lacis, "Gee, by the time we're retirement age, interesting things will be happening on our planet." What we could not have guessed is the fact that the world's governments would be so unresponsive to the increasing empirical evidence. No one expected that governments would react immediately when it was still just based on simple models 40 years ago, but now, it's not just models. We can see what's happening.

e360: It seems as though recently every new scientific article that comes out, every new headline that's published on climate change and climate projections, it's about this abrupt climate change. Is the idea of gradual climate change gone for good now?

Hansen: Some things do change gradually because of the inertia system. The global average temperature, if you average it over several years, is going up pretty smoothly, since the middle 1970s. January/February of this year, global temperature is now 1.3 degrees above the 1950-1980 average, but that was just two months. Averaged over the year, it's going to be about 0.9 degrees Celsius, and that's pretty much on this almost linear increase over the last four decades.

Locally and regionally you get abrupt events, which are the ones that have the biggest impact on people. The frequency and severity of extreme events increase as the planet continues to get warmer. Sea level and ice-sheet disintegration is also a very nonlinear process. It's going to lead to rapid change within the next several decades. The other thing we point out is that the fresh water coming off of Greenland and Antarctica is affecting the ocean circulation. Normally in the winter at the polar regions, it gets cold, the salt in the ocean water gets dense, and will sink toward ocean bottom, and that drives this overturning ocean circulation or conveyor belt. I think there's a danger that if we keep adding greenhouse gases, that we will get shutdown in the AMOC, Atlantic Meridian Overturning Circulation, sooner than the model indicates. It's very interesting scientifically, but it's very threatening.

Sea level changes detected by NASA satellites between 1992 and 2014. Deep red represents 2.7 inches of rise while blue represents a drop in sea level.







e360: You and your colleagues publicized the Atmospheric Chemistry and Physics Discussion study last July, before it had undergone peer review — and received a lot of criticism for doing so. Why did you choose to do that?

Hansen: Because there was going to be a United Nations meeting in December, and we thought these are important considerations that should be included. It makes the urgency of actions clearer. This is a perfectly legitimate. That's the great thing about the journal that we submitted it to, Atmospheric Chemistry and Physics Discussion. If an appropriate editor looks at it and decides that it appears to be reasonable, then they publish it. It's available to anyone in the world. The whole idea is to get discussion, to improve the final paper that comes out.

There's absolutely nothing wrong with this. It is frustrating that some scientists find it objectionable. I think it's exactly the right thing to do, and I think other people should do the same thing, if they have a paper that's important to get the discussion out there.
I find people want to criticize, and they are welcome to do that, but I will gladly do the same thing again.
e360: I know one of the biggest issues with climate denialists have been that they publish studies, but often these are not in peer-reviewed journals. Did you and your colleagues worry at all that following a similar route, publicizing it before it became peer reviewed, might undercut the credibility of the research?

Hansen: It shouldn't. It should increase the credibility. If you've got more opportunity for people to criticize it and to make suggestions, it becomes all the stronger. I find people want to criticize, and they are welcome to do that, but I will gladly do the same thing again.

e360: You support nuclear energy, but many environmentalists don't. What's your argument for supporting it?

Hansen: It's very interesting that environmentalists have become anti-nuclear. If you go back to the middle of last century, environmentalists, at least some of them, pointed out that nuclear energy was probably the best option for the future because it has the smallest footprint on the environment. A ping-pong-ball-sized piece of uranium contains enough energy for a person who lives to be 100 years old. Unlike fossil fuels, it doesn't dump greenhouse gases and aerosols into the atmosphere.

We in the West raised our standard of living by burning fossil fuels. If the rest of the world does the same thing, we're all cooked. China and India know very well they can't get all the energy they need from the sun and the wind — those are useful and they should be part of the clean energy that the world needs, but they're intermittent. They're not a complete solution.

e360: Some people have criticized you for being an alarmist, for using the extremes of climate scenarios when you talk to the media and the public. Do you worry at all that this can be counterproductive? That by saying things like Keystone XL would be "game over for climate," it causes people to throw their hands up in despair and say, "We can't do anything anyway. It's too big of a problem"?

Hansen: The scientific community is getting more and more concerned about the fact that we're pushing the system beyond tipping points and things are happening. I don't think that I have been alarmist — maybe alarming, but I don't think I'm an alarmist. The point of the Keystone XL pipeline comment was that we cannot burn the unconventional fossil fuels without ensuring that young people inherit a situation out of their control.
I don't recommend that all scientists, especially young ones, get arrested. I can afford to do that since I'm beyond retirement age.
e360: When you look at the climate projections for the next 100 years, for your grandchildren's lifetimes, do you think that we have the time and motivation to adapt?

James Hansen
Milan Ilnyckyj/TarSandsAction

Hansen: Some climate change is obviously going to occur which we have to adapt to, but the things you cannot adapt to are what I call the irreparable harm. There are specifically two things that I focus on: One of them we've talked about, that's sea level rise. If ice sheets become unstable, it would cause continually rising sea levels with economic implications that are incalculable. That's irreparable harm to young people. The other thing is extermination of species. If we keep burning fossil fuels business-as-usual, then the climate zones shift fast enough and far enough that it will, in combination with the other stresses on species, cause extermination of a significant fraction of species on the planet. It'll be a much less desirable planet if we drive many species to extinction.

e360: You balance between being a scientist and an activist, a position that many researchers are reluctant to take. When did you feel like you had to take more of an activist role?

Hansen: I don't recommend that all scientists, especially young ones, go out and get arrested. I can afford to do that since I'm beyond retirement age. The first time I got arrested was after young people at Virginia Tech told me about Larry Gibson, who was this man who had a cabin on Kayford Mountain [in West Virginia] and was blocking coal companies by refusing to sell his land. Mountaintop removal is like tar sands. It's a crazy thing. The amount of pollution that you produce locally at the place where you're taking the stuff out of the ground is enormous. They're destroying the groundwater in the surrounding areas. They push the top of the mountains into the valleys where the streams are. The health of people living in West Virginia is significantly impacted by that practice.

e360: Did you feel it hurt you within the scientific community when you started engaging in activism?

Hansen: I don't think so. It's a little surprising to me that the scientific community objected to our recent paper being publicized before the final version was available, but other than that it has been very supportive.
There's no way we can burn all that's available without guaranteeing that it's a completely different planet.
e360: You talked about young scientists maybe not getting into activism, but do you think that this is a role more scientists need to take?

Hansen: I do think that more scientists need to be as clear as they can in communicating the implications of the science to the public. All ages of scientists can do that. We have a society in which most people have become unable to understand or appreciate science, and partly that's a communication problem which we need to try to alleviate.

e360: Fast forwarding a bit to November. Polls show more and more people are concerned about climate change in this country on both sides of the aisle, but the issue has yet to be a major priority for Americans in the voting booth. What do you think would have to change in order for that to happen?

Hansen: Young people need to understand how much is at stake for them. It became a significant issue in the 2008 elections, not a major issue, but Barack Obama did address it in his campaigning. He did say we have a "planet in peril" a number of times. For a number of reasons, young people supported him, and that played a major role in his election. But they didn't know what to ask after he was elected, and so the policies that were proposed by Obama were based on the policies advocated by Big Green, such as cap and trade, and that unfortunately is completely inadequate. The next time around, after this next election, we had better make sure that the new administration understands not only what the problem is, but what will work and what won't work in solutions.

e360: Has the major boom in fracking and in the release of methane into our atmosphere changed how scientists understand and predict climate change impacts? Was this even a factor a decade ago?

Hansen: Fracking has changed the story in a major way. There were scientists who were arguing, "We're at peak oil, peak gas," and so the climate problem will diminish in the future because we're running out of fossil fuels. The fossil fuel industry figured out ways to get a lot more out of the ground, and there's a lot more down there. There's no way we can burn all that's available without guaranteeing that it's a completely different planet. Fracking and tar sands, what I would call unconventional fossil fuels, we just can't afford to burn them. If it were really a bridge that allowed us to close coal, use gas for a little while, while we developed zero carbon energies, that would not be insensible — but that's not what's actually happening. We're still burning coal, and we're burning more gas.

e360: Is there anything else you would like to mention?

Hansen: The one thing, which is most important, is the assertion by the fossil fuel industry and the people who support them, that it would be expensive to solve the problem, is absolutely wrong. There have been economic studies that show if you add a gradually rising fee to fossil fuels, by collecting a fee on fossil fuel companies at the source, the domestic mine, or port of entry, and if you distribute the money to the public, an equal amount to all legal residents, it would actually spur the economy. It would increase the gross domestic product and add millions of jobs. We need to have such a common sense solution, which is revenue neutral, so it doesn't make the government bigger. Instead of proposing taxes or regulations that conservatives will fight tooth and nail, we should find an approach that both liberals and conservatives would be willing to support. That's what needs to be understood, that it's not painful to solve this problem if we are smart, but we have to think this through.

*Katherine Bagley, who conducted this interview, is the web editor of Yale Environment 360.

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How To Talk About Climate Change Without Talking About Climate Change

Sydney University

Adapting to climate change is a politically fraught process. Policymakers' inability to openly discuss climate change is leaving many local councils across Australia unprepared for its impacts, analysis by a PhD candidate at the University of Sydney has found.
Lisette Collins from the Department of Government and International Relations has compiled the first ever database of climate change adaptation plans (CCAPS) developed by local councils nationwide.
Her research reveals vast gaps in the level of detail between plans, with some councils only accounting for physical risks like extreme weather events while omitting other socio-economic impacts, such as how climate change will affect the homeless and elderly.
"Our inability to be able to talk openly about climate change in a rational and constructive way has negative implications for the development of successful adaptation policy in the future," said Collins.
"'Climate change' is a highly politicised term in Australia and one of the most ubiquitous terms of the 21st century. It has been questioned, co-opted, pleaded, adopted, misunderstood, misrepresented, and denigrated at varying times by politicians, the media, academics, scientists, and the public."
While many local councils currently have climate adaptation plans in place, political narratives around climate change have affected public perceptions and awareness of these plans, according to Collins.
It is no coincidence that most Australians don't know what a climate change adaptation plan is or whether their local council has one      Lisette Collins
"Councils are on the frontline of adapting to the impacts of climate change. We need to take a closer look at how adaptation is occurring at this local level if we are to be prepared for the future."
Collins examined 107 CCAPS from across Australia covering over 180 local councils, as well as 20 high-level interviews with local government representatives. The smallest population covered in the plans was 181 people (Belyuen, Northern Territory).
She then categorised these CCAPS into groups based on whether they contained biophysical vulnerabilities – planning for droughts, bushfires and rising sea levels – or socio-political inclusive plans, which refer to vulnerable groups and the mental health impacts of climate change.
It is hoped the database will be used as a tool to assist local governments as they create or update their future adaptation plans.

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