Thursday, February 02, 2006
Reef bleaches, while Howard prevaricates
WHILE GOVERNMENTS representing half the world's population prevaricate over whether to slow their burgeoning greenhouse gas emissions, Australia's Great Barrier Reef is suffering a further bout of coral bleaching. This time, three months earlier than ever before.
University of Queensland scientists studying reefs off Great Keppel Island (at the southern end) have found a major section of bleaching reef. It has the potential to develop into the worst episode yet, as it has occurred so early in the season.
Previous mass bleachings – in 1998 and 2002 – had occurred in April, when the ocean is at its warmest. But persistent settled and hot weather in the region has led to early bleaching, even before the hottest month, February, has begun.
Coral bleaching occurs when the water gets too warm, too quickly. A rise of 3º can lead to devastated reefs.
Coral's colour is a result of its symbiotic relationship with zooxathelle (algae) which live within the coral animal. Stress factors – such as rapidly warming water – cause algae to spontaneously vacate its coral host, thus sapping it of colour. Swathes of reef can turn a ghostly white.
If tolerable conditions return within a couple of months, the algae will happily return and their cosy and productive relationship with their coral hosts can pick-up where it left off.
But if the relationship is broken for longer, the coral dies back and whole reefs can be trashed. Green algae will quickly coat the coral skeletons and disease takes over. Recovery – if it occurs at all – takes many years.
The scientists studying the Great Keppel Island coral argue that continuing settled weather could spell disaster.
As well as being unsightly, coral bleaching has a massive impact on the complex reef ecosystem, devastating local fish stocks and reef productivity. Large areas of the Indian Ocean - East African, Sri Lanka, Seychelles and Maldives - have already been destroyed.
For these communities, damaged reefs (much like destroyed mangroves) mean damaged livelihoods with wild fish take, already depleted by over-exploitation and pollution, robbed of its reproductive potential.
Similarly, any severe damage to the Great Barrier Reef will also have an impact on the Australian economy, not least because of its value to tourism. The Great Barrier Reef Marine Park Authority have calculated that the reef is worth $5.1bn per year to Australia; tourism makes up 87% of this.
Like unseasonably hot weather, coral bleaching is an 'event' and – as such – cannot be unquestionably attributed to anthropogenic global warming (AGW). That said, a body of water the size of the Coral Sea takes an immense amount of energy to heat up. Higher temperatures are attributed to persistent El Nino conditions, which is predicted as a result of climate change modelling with increasing greenhouse gas.
So while this single despoilation cannot be assigned to global warming, realclimate.org's dice analogy provides an insightful view on the effects of continued pollution (using Hurricane Katrina as an example:
WITH CRUEL irony, the desolation of the Great Barrier Reef could be a good thing. Already, Australians suffer from the effects of AGW, with many of the major cities facing severe water shortages, for example. But the widespread destruction of one of the nation's foremost natural icons could offer the right incentive to shake Australians out of their mass-cognitive dissonance: "See no evil. Hear no evil. Speak no evil".
However, John Howard's recent stark analysis - that we cannot continue to increase our prosperity without the use of fossil fuels – is a sad reminder that we are stuck with compromised politicians who cannot see beyond the next round of political donations.
The Australian landscape and its ecosystems will become irreparable damaged by the attitudes of our political leadership which helps shape (by doctoring information) public opinion on complex issues such as global warming. But whilst most Australians would care little - nor notice - the extinction of say, a dozen species of rainforest frog (whose rainforest habitat is being pushed ever upwards until it runs out of mountain), it might just take note of the destruction of the largest living land mass on the planet.
Particularly, when it begins to damage the economy.
Reef bleaches, while Howard prevaricates
Posted by Living with Matilda at 12:57 PM
WHILE GOVERNMENTS representing half the world's population prevaricate over whether to slow their burgeoning greenhouse gas emissions, Australia's Great Barrier Reef is suffering a further bout of coral bleaching. This time, three months earlier than ever before.University of Queensland scientists studying reefs off Great Keppel Island (at the southern end) have found a major section of bleaching reef. It has the potential to develop into the worst episode yet, as it has occurred so early in the season.
Previous mass bleachings – in 1998 and 2002 – had occurred in April, when the ocean is at its warmest. But persistent settled and hot weather in the region has led to early bleaching, even before the hottest month, February, has begun.
Coral bleaching occurs when the water gets too warm, too quickly. A rise of 3º can lead to devastated reefs.
Coral's colour is a result of its symbiotic relationship with zooxathelle (algae) which live within the coral animal. Stress factors – such as rapidly warming water – cause algae to spontaneously vacate its coral host, thus sapping it of colour. Swathes of reef can turn a ghostly white.
If tolerable conditions return within a couple of months, the algae will happily return and their cosy and productive relationship with their coral hosts can pick-up where it left off.
But if the relationship is broken for longer, the coral dies back and whole reefs can be trashed. Green algae will quickly coat the coral skeletons and disease takes over. Recovery – if it occurs at all – takes many years.
The scientists studying the Great Keppel Island coral argue that continuing settled weather could spell disaster.
As well as being unsightly, coral bleaching has a massive impact on the complex reef ecosystem, devastating local fish stocks and reef productivity. Large areas of the Indian Ocean - East African, Sri Lanka, Seychelles and Maldives - have already been destroyed.
For these communities, damaged reefs (much like destroyed mangroves) mean damaged livelihoods with wild fish take, already depleted by over-exploitation and pollution, robbed of its reproductive potential.
Similarly, any severe damage to the Great Barrier Reef will also have an impact on the Australian economy, not least because of its value to tourism. The Great Barrier Reef Marine Park Authority have calculated that the reef is worth $5.1bn per year to Australia; tourism makes up 87% of this.
Like unseasonably hot weather, coral bleaching is an 'event' and – as such – cannot be unquestionably attributed to anthropogenic global warming (AGW). That said, a body of water the size of the Coral Sea takes an immense amount of energy to heat up. Higher temperatures are attributed to persistent El Nino conditions, which is predicted as a result of climate change modelling with increasing greenhouse gas.
So while this single despoilation cannot be assigned to global warming, realclimate.org's dice analogy provides an insightful view on the effects of continued pollution (using Hurricane Katrina as an example:
it is wrong to blame any one event, such as Katrina, specifically on global warming - and of course it is just as indefensible to blame Katrina on a long-term natural cycle in the climate.
Yet this is not the right way to frame the question. [..] we can indeed draw some important conclusions about the links between hurricane activity and global warming in a statistical sense. The situation is analogous to rolling loaded dice: one could, if one was so inclined, construct a set of dice where sixes occur twice as often as normal. But if you were to roll a six using these dice, you could not blame it specifically on the fact that the dice had been loaded. Half of the sixes would have occurred anyway, even with normal dice. Loading the dice simply doubled the odds. In the same manner, while we cannot draw firm conclusions about one single hurricane.
http://www.realclimate.org/index.php?p=181
Yet this is not the right way to frame the question. [..] we can indeed draw some important conclusions about the links between hurricane activity and global warming in a statistical sense. The situation is analogous to rolling loaded dice: one could, if one was so inclined, construct a set of dice where sixes occur twice as often as normal. But if you were to roll a six using these dice, you could not blame it specifically on the fact that the dice had been loaded. Half of the sixes would have occurred anyway, even with normal dice. Loading the dice simply doubled the odds. In the same manner, while we cannot draw firm conclusions about one single hurricane.
http://www.realclimate.org/index.php?p=181
WITH CRUEL irony, the desolation of the Great Barrier Reef could be a good thing. Already, Australians suffer from the effects of AGW, with many of the major cities facing severe water shortages, for example. But the widespread destruction of one of the nation's foremost natural icons could offer the right incentive to shake Australians out of their mass-cognitive dissonance: "See no evil. Hear no evil. Speak no evil".
However, John Howard's recent stark analysis - that we cannot continue to increase our prosperity without the use of fossil fuels – is a sad reminder that we are stuck with compromised politicians who cannot see beyond the next round of political donations.
The Australian landscape and its ecosystems will become irreparable damaged by the attitudes of our political leadership which helps shape (by doctoring information) public opinion on complex issues such as global warming. But whilst most Australians would care little - nor notice - the extinction of say, a dozen species of rainforest frog (whose rainforest habitat is being pushed ever upwards until it runs out of mountain), it might just take note of the destruction of the largest living land mass on the planet.
Particularly, when it begins to damage the economy.
Posted by Living with Matilda at 12:57 PM
Disclaimer:
| I am employed by Brisbane City Council. All views expressed in this blog are my own and in no way reflect the views of my employer. |
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2 Comments:
Interesting that the Fox News article "Bad(!) Coral Bleaching along Great Barrier Reefs" does not report Professor Ove Hoegh-Guldberg's assertions that the bleaching could be connected in some way to anthrogenic global warming!!!
Sorry, link is:http://www.foxnews.com/story/0,2933,183419,00.html
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