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The Great Barrier Reef needs emissions cuts of 25% to avoid "death row"

The Great Barrier Reef is one of the seven wonders of the natural world.

It is larger than the Great Wall of China and the only living thing on earth visible from space.
The Great Barrier Reef includes over 2,900 reefs, around 940 islands and cays, and stretches 2,300 kms along the Queensland coastline. The Great Barrier Reef Marine Park is 345,000 km2, that's larger than the entire area of the UK and Ireland combined!
The Great Barrier Reef (GBR) contributes $5.4 billion annually to the Australian economy - $5.1 billion from the tourism industry; $153 million from recreational activity; and $139 million from commercial fishing.
Over the past one hundred years, the temperature of sea water in many tropical areas has been rising. For example, the Australian Institute of Marine Science has collated data showing that 2002 was the warmest year for water temperatures off northeast Australia since 1870.

Impacts on the GBR causing bleaching:

Rising water temperatures block the photosynthetic reaction that converts carbon dioxide into sugar. This results in a build-up of products that poison the zooxanthellae, the single-celled plants that live in the tissues of animals. They are dinoflagellates, a group of microscopic plants which are usually found swimming and floating in the sea. Organisms which live like this are called plankton, and those that are plants are called phytoplankton. To save itself, the coral spits out the zooxanthellae and some of its own tissue, leaving the coral a bleached white.

In Australia alone, the 2002 bleaching saw nearly 60 per cent of the reef suffer bleaching and, in the worst areas, 90 per cent of the coral was bleached.

Coral reef bleaching is caused by various anthropogenic and natural variations in the reef environment including sea temperature, solar irradiance, sedimentation, subaerial exposure, inorganic nutrients, freshwater dilution, and epizootics (a disease that appears as new cases in a given animal population, during a given period, at a rate that substantially exceeds what is "expected" based on recent experience). Coral bleaching events have been increasing in both frequency and extent worldwide in the past 20 years.

[Tridacna crocea giant clam. Although in the giant clam family this small clam rarely gets more than 10 centimeters long. This species is normally found in shallow intertidal reef flats where its symbiotic zooxanthellae can get the most sunlight for photosynthesis. ] photo courtesy Wikimedia commons.

Federation of Australian Scientific and Technological Societies told a meeting at the Canberra parliament:

Climate Change Alliance scientists briefed
from all sides (17th Nov) that the reef is facing a bleak future.

The Alliance, which is led by Federation of Australian Scientific and Technological Societies president Ken Baldwin, will warn MPs and senators that the reef is on the frontline of climate change.

Professor Terry Hughes and representatives told the meeting at the Canberra parliament that the future of the reef, and a large chunk of Australia's tourist industry, was under grave threat from rising sea temperatures.

Global carbon emissions must be cut by at least 25 per cent by 2020 to give the Great Barrier Reef a better than 50/50 chance of survival, the alliance of Australia's reef and climate scientists says.

The 13 scientists said even deeper cuts of up to 90 per cent by 2050 would be necessary if the reef were to survive future coral bleaching and coral death caused by rising ocean temperatures.

“We’ve seen the evidence with our own eyes. Climate change is already impacting the Great Barrier Reef,” Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, said in a briefing to Australian MPs.

Damage to habitat of marine species:

Professor Charlie Veron, Prof. Hoegh-Guldberg, Dr Janice Lough of Centre Of Excellence Coral Reef Studies
and the Australian Institute of Marine Science and colleagues warn in a new scientific paper published in the Marine Pollution Bulletin: 'Damage to shallow reef communities will become extensive with consequent reduction of biodiversity followed by extinctions,' they add. 'Reefs will cease to be large-scale nursery grounds for fish and will cease to have most of their current value to humanity. There will be knock-on effects to ecosystems associated with reefs, and to other (marine) ecosystems.'

Prof Veron told the British Royal Society recently that Australia’s Great Barrier Reef would be on ‘death row’ unless urgent action was taken to stem global carbon emissions.

'We are tracking the IPCC’s worst case scenario. The global CO2 situation, tracked by temperature and sea level rise, is now following the worst case scenario,' he says. 'The people meeting at Copenhagen need to hear this message.'

Prof Hoegh-Guldberg warns 'We are already well above the safe levels for the world’s coral reefs....
'We are already well above the safe levels for the world’s coral reefs. The proposed 450ppm/2 degree target is dangerous for the world’s corals and for the 500 million people who depend on them.'

Prof Veron: "It will cost less than 1 per cent of GDP growth (over the next 50 years) to sort this problem out. In times of war individual countries have devoted anything from 40 to 70 per cent of their GDP to the war effort, so the effort required to cease emitting carbon is far, far smaller. It is completely affordable, completely achievable.

The Solution- emissions reduction:

"The Great Barrier Reef will only survive if greenhouse gas emissions are reduced by at least 25 per cent and even then that only gives it an even money chance,'' Baldwin said.

It has said it would go further, with a 25 per cent cut, if a tough international climate agreement is reached at UN climate talks in Copenhagen in December, but this is looking increasingly unlikely with legally binding targets now off the agenda.

"Unprecedented coral bleaching and extensive mortality due to thermal stress affected over 50 per cent of the GBR in 1998 and 2002, when summer maximum water temperatures were elevated by only 1-2oC," The University of Queensland's Professor Ove Hoegh-Guldberg said.

Other threats to GBR:

Over-fishing is another cause for concern because when parrotfish and large herbivorous fish are removed from reef food webs, it allows an increase in Sargassum algae and cyanobacteria that form large beds over the coral. This blocks off the light to the zooxanthellae algae and affects the resilience of corals. That is, it affects their ability to recover from coral bleaching events.

Tougher regulations on farm chemicals are needed following rain that caused one million megalitres of pollution to spew into the great barrier reef, environmentalists say. Relatively low levels of herbicide residues can reduce the productivity of marine plants and corals. However, the risk of these residues to Great Barrier Reef ecosystems has been poorly quantified due to a lack of large-scale datasets. Elevated herbicide concentrations were particularly associated with sugar cane cultivation in the adjacent catchment.

5% reduction in CO2 is not enough:

Australia is one of the world's biggest CO2 emitters per capita, but has only pledged to cut its emissions by five per cent from 2000 levels by 2020. The UN Intergovernmental Panel on Climate Change has concluded that the Great Barrier Reef could be "functionally extinct" within decades, with deadly coral bleaching likely to be an annual occurrence by 2030.

Our environmental “capital” has intrinsic, financial, ecological, environmental and socials value, but without an exact dollar value, it is easily dismissed in the quest for industrialisation, growth, profits and exports. The GBR is an area of great beauty, complexity and mystery. We need to understand the massive stresses our cities and industries are placing on these dynamic and fragile ecosystems.

If the environmental cost of population growth and a developed economy is the loss of our natural heritage and world-famous resources, then the growth mentality of our leaders and economists needs to change with the changing environment.

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Why worry? It WILL go back down all by it's self when it's good and ready. It allways correlates with Glacier retractions and expansions and periods of extra sizmicity because of emissions from hot rock
This is where Ian Plimer is right but misunderstood with volcano emissions
Not all CO2 comes from volcanic lava.

CO2 released from hot rocks and Earthquakes produce carbon dioxide in crustal faults.




3 MILLION + submarine volcanoes and a 'billion' Superheated Thermal Vents.


Based on continental and oceanic studies, the atmosphere had ~30% higher CO2 concentrations than pre-Industrial Holocene levels (Kürschner et al., 1996; Raymo et al., 1996).

Not all CO2 comes from volcanic lava.

An estimated 85 percent of all forms of seismic activity happens out of sight under oceans at plate boundaries.

More is now known of undersea hot rock emissions of CO2, CO2 released from hot rocks and
Earthquakes produce carbon dioxide in crustal faults;.265..487F


An estimated 3 MILLION plus undersea volcanoes, probably a BILLION plus superheated hot water thermal vents which may have increased parallel with CO2. Just as it HAS happened EVERY time at the start of each Deep Ice Age.


Find out about the stark truth about The Great Barrier Reef acidification by reviewing two recent studies:

Subject was: "We cannot have limitless growth on finite ecosystems." - JS

Outbreaks of toxic blue-green algae and infestation by pest species such as the crown-of-thorns starfish appeared to be becoming more frequent and more serious in the Great Barrier Reef. "Improving the quality of water flowing into the reef is one of the most important things we can do to help the reef withstand the impacts of climate change," Environment Minister Peter Garrett said. How do we stop the effects of industrialisation, agriculture and the global shipping trade?

Ocean acidification, caused by increasing levels of dissolved carbon dioxide, is a newly recognised and serious threat to the reef.

Hoegh-Guldberg, head of the University of Queensland's Centre for Marine Studies, argues that coral reefs will likely recover in geologic terms, but not in terms of a human lifetime. The short term impact of dying and degraded reefs will be significant. Hoegh-Guldberg suspects corals will face a difficult adjustment period in the face of rapidly rising sea temperatures and falling carbonate ion concentrations. He argues that coral reefs will likely recover in geologic terms, but not in terms of a human lifetime.

A decline in the number of small fish meant lower numbers of predatory fishes such as high-value commercial and recreational species such as coral trout. This exposed them to predators that snapped them up.

The GBR is home to significant biodiversity, including more than 4000 mollusc species, around 1500 fish species, most of the world’s marine turtle species, the dugong, and many species of whale and dolphin, with possibly more yet to be discovered.

There is more than tourism dollars at stake! Unusually high sea temperatures in the Great Barrier Reef have already led to mass die-offs of seabird chicks, from parent birds being unable to find enough prey as fish populations have moved. The sex and viability of sea turtle hatchlings depends on sand temperature, and warming could lead to a significant bias towards females and potentially a decline in future populations.

There is more than the economy at stake! British economist Sir Nicholas Stern says that climate change could shrink the global economy by as much as 20%. Maybe these dramatic changes to our ecology and economy, the latter being dependent on the former, is the cost of a wake-up call that growth in our economy and human numbers cannot be limitless on finite ecosystems.

An excellent and well researched article Vivienne.

This is a national ecological emergency. It is where Bligh and Rudd should be focusing, not on kangaroo meat exports or intangible ETS appeasement.

According to a ten year old study by the CRC Reef Research Centre & James Cook University "Tourism is the activity with the highest commercial value within the Great Barrier Reef Marine Park (GBRMP) (GBRMPA 2000a). Approximately 1.6 million visitors travel to or through the GBRMP on commercial tourism operations each year. In addition, more than one million visitor nights per year are spent in accommodation on island resorts within the boundaries of GBRMP (extrapolated from Driml 1987, Zann 1996). The direct value of marine tourism is over $1 billion per year (Zann 1996, Dinesen and Oliver 1997, GBRMPA 2000a), approximately four times that of the next most valuable commercial activity, i.e. commercial fishing.

The marine tourism industry is a major contributor to the Australian economy, with an estimated direct value in excess of $1 billion (Wachenfeld et al 1998, GBRMPA 2000a). Total employment was estimated at 120,000 people (Zann 1996)."

Queenslanders don't realise what's looming. The bleaching of the Reef threatens to ruin GBR marine tourism and with it to instigate a recession across the Queensland economy. Beautiful one day...

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