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畜牧業、肉食對環境與健康的危害
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海洋酸化
地球越來越熱有一個關鍵點是在海洋，海洋會吸收二氧化碳，但海洋吸收的速度無法平衡空氣中二氧化碳的排放量（碳循環），使得空氣中二氧化碳累積起來，於是濃度不斷增加，吸收了太陽光熱能（或阻擋熱能回到太空）而導致地球溫度上升。
我們破壞海洋太快、太嚴重了，包含漁撈、污染、酸化．．我們的海洋嚴重枯竭，像沙漠一樣了無生機，幾近飽和，已失去吸收二氧化碳的能力了，而畜牧業所排放的糞肥，大量地進入海洋，導致海水酸化，尤其是美國！
海洋酸化的危機：
台灣動物社會研究社的資料：
http://www.east.org.tw/18/book-3.html
數以「億」計算的豬（10億）、牛（13億）、羊（18億）、雞（154億），不管是紅肉還是白肉，如果沒有做好糞肥管理，可說是海洋的災難，不只是糞肥， 還有腸氣、糧食效率、水、土地、森林砍伐（砍掉改成牧場或種飼料的農場）、疾病成本．．禽流感、倒地牛、口蹄疫、病死豬（如果你投資了一千萬養了半年的豬，結果病死了一堆，回頭看看家裡的老小，你會怎麼辦？）別說宗教因果、道德、愛護動物了。
所以我們要如何計算肉品的碳足跡？不能只算二氧化碳，蔬食抗暖化是在救你，救你的小孩！
那些研究報告都是無宗教信仰的科學家們，用數字、統計、採樣、驗證．．得來的，國際新聞上我沒有看到反駁的研究論文，他們只有增加投資解決污染的路，要不然就是指責別的產業說：解決汽車排放污染才是解除地球暖化根本之道。
先放棄畜牧業，掙取時間來：1.降低太陽能成本使其普及，2.發展零碳引擎，3.海洋復育．．等等。
企業家想要再享受財富100年，大老闆最好是推動素食午餐政策，在公司餐廳裡一旁免費提供員工素食午餐。
五座水庫水質差 養豬廢水是主因
2008/05/06, 公共電視
http://tw.news.yahoo.com/article/url/d/a/080506/51/ynvz.html
我們每天喝的水到底乾不乾淨呢？最近環保署檢測全台二十座水庫，發現優養化的水庫，已經從八座減少到五座，另外河川的水質也有改善，嚴重污染的河段減少了，而台灣最髒河川，已經由北港溪取代了二仁溪。
雖然水庫水質有改善，不過還是有五座水庫水質很差，呈現優養化，包括寶山、白河、澄清湖、鳳山以及阿公店，其中四座在於南部，最主要是因為水庫上游河川被排入養豬廢水，污染難以改善。至於北港溪取代二仁溪成了最髒的河川，一樣也是養豬廢水所造成的。
缺氧海洋區擴大中
Oxygen-depleted ocean zones are growing
May 1, 2008, United Press International
http://www.upi.com/NewsTrack/Science/2008/05/01/oxygen-depleted_ocean_zones_are_growing/1152/
KIEL, Germany, May 1 (UPI) -- German-led scientists say they've confirmed computer predictions that oxygen-depleted zones in tropical oceans are expanding, possibly due to climate change.
The researchers led by Lothar Stramma from the Leibniz Institute of Marine Sciences in Kiel, Germany, discovered oxygen levels in tropical oceans at depths of 985 to 2,300 feet have declined during the past 50 years. The ecological impact of that decline and the growth of such areas, the scientists said, could have substantial biological and economic consequences.
The study involved an analysis of an historical database of ocean oxygen measurements.
"We found the largest reduction … in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced," said Stramma. "Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales."
The study that included U.S. National Oceanic and Atmospheric Administration scientist Gregory Johnson, Janet Sprintall of the Scripps Institution of Oceanography in San Diego and Volker Mohrholz from the Institute for Baltic Sea Research in Warnemunde, Germany, appears in the journal Science.
海洋沙漠化擴大中
'Ocean deserts' are growing
Low-oxygen regions have expanded over the past half-century.
1 May 2008, Nature, Michael Hopkin
http://www.nature.com/news/2008/080501/full/news.2008.795.html?s=news_rss
Low-oxygen 'underwater deserts' in the tropical oceans have expanded over the past 50 years, according to new measurements. The most likely cause of the change is global warming, and climate models predict that the trend will continue, potentially threatening marine ecosystems.
The discovery concerns a layer of the ocean called the 'oxygen-minimum zone', where concentrations of dissolved oxygen are particularly low. The new study shows that this zone has been expanding both upwards and downwards into the adjacent layers in tropical waters.
Climate models predict that warming of the sea's surface as a result of human activity will hamper the mixing of oceanic waters, preventing dissolved oxygen from mixing evenly through the water column. The new results suggest that this process has already begun.
Researchers led by Lothar Stramma of the University of Kiel, Germany, measured the oxygenation of the oceans at depths of between 300 and 700 metres during a series of observation cruises in tropical regions of the world's three main oceans. They added their new data to previous oxygen measurements to build up a picture of the trend over the past 50 years.
Overall levels of oxygen have dropped in these zones, Stramma and his colleagues report in Science 1. Regions of the eastern tropical Pacific Ocean and the northern reaches of the Indian Ocean are now classed as 'suboxic', meaning that the amount of oxygen has dropped sufficiently to harm the functioning of ecosystems.
Starving waters
In suboxic waters, nitrogen cannot react with oxygen to form biologically available nitrate. This means that organisms at the base of food chains, such as plankton, do not get enough nutrients to survive, Stramma explains.
The ultimate effect on commercially important ecosystems such as fisheries are difficult to predict, Stramma adds. "There are many complicated mechanisms involved that we need to understand better to predict changes for the future," he says. "I see our results as a starting point to be able some day to tell what changes in biogeochemistry, biology and fisheries we have to expect."
Any effect on fisheries is likely to be indirect, because these low-oxygen zones are far from the coastal waters that host most commercial fishing, suggests Andrew Solow, director of the Marine Policy Center at Woods Hole Oceanographic Institution in Massachusetts. "I don't know many fisheries that take place between 300 and 700 metres in the tropical ocean," he says.
These 'underwater deserts' should not be confused with the 'dead zones' created in coastal waters, most famously in the Gulf of Mexico, by runoff of nitrogen-rich fertilizer, Solow adds. Coastal waters lose their oxygen as a result of booms in phytoplankton growth; when these organisms die, they provide food for microbes that suck up all of the oxygen.
Going down
"It's a worrying trend," comments Laurence Mee, director of the Marine Institute at the University of Plymouth, UK. "This is one more piece in the argument that we need to do something about climate change."
Mee agrees that it's quite difficult to say whether, or how much, the decline in oxygen levels will affect ecosystems, including economically important ones. If the low-oxygen zones extend closer to the surface, they may reach the shallow, sunlit waters where many valuable fish species live. "When you start to mess around with the food chain, it has all kinds of knock-on effects that we don't know about yet," Mee says.
Team member Gregory Johnson of the National Oceanic and Atmospheric Administration in Seattle says that he and his colleagues now plan to take more measurements, to see whether the low-oxygen zones are spreading across the oceans, or spreading upwards and downwards within the water column.
當我們的海洋變酸
When our oceans turn sour
April 21, 2008, Ross Allen and Anthony Bergin
http://www.theage.com.au/news/opinion/when-our-oceans-turn-sour/2008/04/20/1208629730189.html
CLIMATE change is a core issue on the Rudd Government's agenda. But there's another carbon problem that has been avoided and is largely independent of global warming.
In a speech to the Australian Strategic Policy Institute last week on Australia's focus on the Pacific, parliamentary secretary for Pacific Island affairs Duncan Kerr pointed to the effect of marine acidity on coral reefs, the backbone of economic activity for many islander communities. Kerr noted that if land drowns and coral reefs die, the Pacific faces mass movements of people, presenting strategic and humanitarian challenges for Australia.
Confronting the profound problem of acid oceans that could devastate ocean life would demonstrate the Government's commitment to communities dependent on coastal resources in Australia, the Indian Ocean and South Pacific, as well as dealing with long-term global change.
Rising levels of carbon dioxide in the Southern Ocean are alarming scientists concerned about the productivity of oceans. As human activity introduces increasing amounts of carbon dioxide into the atmosphere, the ocean becomes more acidic.
The Southern Ocean is particularly important, because it is efficient at absorbing carbon dioxide from the atmosphere: it is here that the first effects are being felt.
Under conditions of increasing acidification, parts of the oceans will progressively become uninhabitable for certain types of plankton, the earth's most important life forms, and coral structures.
Some shell-forming species will struggle to reproduce vital shell structures and skeletons, which will have a direct effect on the ocean food web. Some species will decline, some will be displaced or will disappear and patterns of fisheries will change. Coral reefs, such as the Great Barrier Reef, will also suffer. Coral skeletons will become weaker and growth rates will reduce, leading to a significant decline by the middle of this century. This will deprive parts of our coastline of a natural protective barrier against the ocean, leading to greater threats from storm activity.
Similarly, environmental threats to states in our region with extensive coastal exposure will increase, resulting in more demands on Australia to assist Pacific Island countries with environmental disasters.
The size and global circulation of the oceans restrict the option of a preventive solution to acidification — such as adding ground limestone. So we need to learn how to adapt.
The Government has an opportunity to strengthen its environmental credentials by addressing the problem of ocean acidification.
There are four initial steps we should take.
First, we need a more collaborative national research effort. The current arrangement of loosely associated research institutions lacks the funding and co-ordination to develop an accurate national assessment of the problem.
Second, we need to address our marine research capability. Australia has only two major research platforms and both vessels are approaching the end of their useful lives. We have less capacity than many of our neighbours and are barely on par with New Zealand. As a stopgap measure we could use merchant vessels to begin a national monitoring program by collecting water samples.
Third, Australia should
take the lead in monitoring acidification levels in regional waters, especially in the Southern Ocean, and raise the issue of how to sustain our oceans at every opportunity in international bodies.
Many of our regional neighbours depend on coral reefs for tourism, and fish stocks in South-East Asia support some 20 million people. Acidification is therefore likely to generate increased calls for our development assistance.
And finally our security decision-makers need to factor ocean acidification into longer-term national risk assessments. Talking directly to Australia's marine science experts would be a sound place to start.
We have a larger stake in this issue than most countries. We are an oceanic superpower, with the third largest area of offshore marine estate in the world. Australian fisheries generate $2 billion in revenue and the Barrier Reef supports a $6.9 billion industry. And we are close to the Southern Ocean: the chilly waters to our south are the principal means for pumping carbon dioxide out of the atmosphere. That's where the warning bells are ringing.
As the planet warms, there will be winners and losers, but with acidification there are only losers. The need to understand the processes and manage this potential peril is getting more urgent.
Ross Allen and Anthony Bergin are researchers at the Australian Strategic Policy Institute.
酸的海洋可能是浮游生物的生命之水
Acidic oceans may be water of life for plankton
18 April 2008, NewScientist.com news service, Kate Ravilious
http://environment.newscientist.com/channel/earth/climate-change/dn13735-acidic-oceans-may-be-water-of-life-for-plankton.html?feedId=climate-change_rss20
Most life in the ocean will suffer as carbon dioxide levels increase and the water becomes more acidic. Some plankton will buck the trend, however, thriving and putting on weight as carbon dioxide levels rise – but it remains to be seen how this will affect the global carbon balance.
Débora Iglesias-Rodríguez, from the National Oceanography Centre at the University of Southampton, UK, and her colleagues, simulated the increase in dissolved carbon dioxide in surface ocean waters by bubbling carbon dioxide through cultures of coccolithophores, a type of single-celled photosynthesising plankton.
In previous experiments water acidity had been regulated by simply adding acid or base, but this method has been criticised for being too artificial. Iglesias-Rodríguez's method found that higher carbon dioxide concentrations increased calcification, speeding up growth of the tiny calcite plates on the plankton cell.
Carbon storage
Coccolithophores appear to benefit in two ways. The extra carbon dioxide aids photosynthesis, while the more acidic waters increase the concentration of bicarbonate – the main ingredient for coccolith plates, known as liths. Making the liths results in the release of carbon dioxide, but when dead plankton fall to the ocean floor the organic matter in their bodies can end up locked away in deep ocean sediments.
"Increased bicarbonate appears to stimulate an increase in mass of calcium carbonate produced by each coccolithophore cell," says Paul Halloran, a co-author from the University of Oxford.
The team's result is not confined to the lab. By studying fossil coccolithophores from a deep ocean core, they found that there has been a 40% increase in average coccolith mass over the last 220 years, mirroring the rise in carbon dioxide levels.
Other scientists think the results make sense and help to explain how coccolithophores survived the last rapid global warming event – the Palaeocene-Eocene thermal maximum 56 million years ago.
Cocco and insensitive
"Coccolithophores seemed to sail through the surface water acidification then, so perhaps they are quite insensitive to this kind of change," says Paul Bown from University College London.
As yet it isn't clear how these super-sized coccolithophores will affect the global carbon balance. If the oceans become too acidic, the shells of dead plankton will dissolve and release their carbon before they fall to the ocean floor.
"We can't yet be confident that stimulating plankton production will draw down carbon dioxide," says Bown.
隨著全球暖化，海洋沙漠化擴大
Ocean "deserts" expand with global warming
March 5, 2008
http://blog.seattlepi.nwsource.com/environment/archives/133510.asp
Increased carbon dioxide emissions are not kind to the world's oceans. It makes them more acidic, potentially dissolving some types of marine life. It makes them warmer, killing coral and sending mobile creatures on a search for cooler water. And now it seems that it's expanding "deserts" where there's less life.
Researchers with NOAA (National Oceanic and Atmospheric Administration) are reporting in the journal Geophysical Research Letters that areas of low productivity -- i.e. less plant life -- increased 15 percent from 1998 and 2007. That's an increase of 6.6 million square kilometers in the Pacific and Atlantic Oceans. The expansion lines up with an increase in the ocean surface temperature of approximately .02 to .04 degrees Celsius a year.
The science at work is pretty straightforward. As the surface of the water warms, it becomes more stratified (imagine it like a cake -- upper layer warm water, lower layer cold water). That prevents the colder, nutrient rich water from mixing with the upper layers. Without the nutrients, there's nothing to feed algae that help sustain other marine life.
The researchers did offer a caveat as regards the long-term trend, as taken from a NOAA press release:
"The fact that we are seeing an expansion of the ocean's least productive areas as the subtropical gyres warm is consistent with our understanding of the impact of global warming. But with a nine-year time series, it is difficult to rule out decadal variation," said Jeffrey J. Polovina, an oceanographer with NOAA's National Marine Fisheries Service in Honolulu, who authored the study along with NOAA's Evan A. Howell and Melanie Abecassis of the University of Hawaii.
These barren areas are found in roughly 20 percent of the world's oceans and are within subtropical gyres -- the swirling expanses of water on either side of the equator.
The desert was measured using NASA's orbiting SeaStar spacecraft and a sensor that measures the density of chlorophyll in phytoplankton, or algae.
地球越來越熱有一個關鍵點是在海洋，海洋會吸收二氧化碳，但海洋吸收的速度無法平衡空氣中二氧化碳的排放量（碳循環），使得空氣中二氧化碳累積起來，於是濃度不斷增加，吸收了太陽光熱能（或阻擋熱能回到太空）而導致地球溫度上升。
我們破壞海洋太快、太嚴重了，包含漁撈、污染、酸化．．我們的海洋嚴重枯竭，像沙漠一樣了無生機，幾近飽和，已失去吸收二氧化碳的能力了，而畜牧業所排放的糞肥，大量地進入海洋，導致海水酸化，尤其是美國！
海洋酸化的危機：
台灣動物社會研究社的資料：
http://www.east.org.tw/18/book-3.html
數以「億」計算的豬（10億）、牛（13億）、羊（18億）、雞（154億），不管是紅肉還是白肉，如果沒有做好糞肥管理，可說是海洋的災難，不只是糞肥， 還有腸氣、糧食效率、水、土地、森林砍伐（砍掉改成牧場或種飼料的農場）、疾病成本．．禽流感、倒地牛、口蹄疫、病死豬（如果你投資了一千萬養了半年的豬，結果病死了一堆，回頭看看家裡的老小，你會怎麼辦？）別說宗教因果、道德、愛護動物了。
所以我們要如何計算肉品的碳足跡？不能只算二氧化碳，蔬食抗暖化是在救你，救你的小孩！
那些研究報告都是無宗教信仰的科學家們，用數字、統計、採樣、驗證．．得來的，國際新聞上我沒有看到反駁的研究論文，他們只有增加投資解決污染的路，要不然就是指責別的產業說：解決汽車排放污染才是解除地球暖化根本之道。
先放棄畜牧業，掙取時間來：1.降低太陽能成本使其普及，2.發展零碳引擎，3.海洋復育．．等等。
企業家想要再享受財富100年，大老闆最好是推動素食午餐政策，在公司餐廳裡一旁免費提供員工素食午餐。
五座水庫水質差 養豬廢水是主因
2008/05/06, 公共電視
http://tw.news.yahoo.com/article/url/d/a/080506/51/ynvz.html
我們每天喝的水到底乾不乾淨呢？最近環保署檢測全台二十座水庫，發現優養化的水庫，已經從八座減少到五座，另外河川的水質也有改善，嚴重污染的河段減少了，而台灣最髒河川，已經由北港溪取代了二仁溪。
雖然水庫水質有改善，不過還是有五座水庫水質很差，呈現優養化，包括寶山、白河、澄清湖、鳳山以及阿公店，其中四座在於南部，最主要是因為水庫上游河川被排入養豬廢水，污染難以改善。至於北港溪取代二仁溪成了最髒的河川，一樣也是養豬廢水所造成的。
缺氧海洋區擴大中
Oxygen-depleted ocean zones are growing
May 1, 2008, United Press International
http://www.upi.com/NewsTrack/Science/2008/05/01/oxygen-depleted_ocean_zones_are_growing/1152/
KIEL, Germany, May 1 (UPI) -- German-led scientists say they've confirmed computer predictions that oxygen-depleted zones in tropical oceans are expanding, possibly due to climate change.
The researchers led by Lothar Stramma from the Leibniz Institute of Marine Sciences in Kiel, Germany, discovered oxygen levels in tropical oceans at depths of 985 to 2,300 feet have declined during the past 50 years. The ecological impact of that decline and the growth of such areas, the scientists said, could have substantial biological and economic consequences.
The study involved an analysis of an historical database of ocean oxygen measurements.
"We found the largest reduction … in the tropical northeast Atlantic, whereas the changes in the eastern Indian Ocean were much less pronounced," said Stramma. "Whether or not these observed changes in oxygen can be attributed to global warming alone is still unresolved. The reduction in oxygen may also be caused by natural processes on shorter time scales."
The study that included U.S. National Oceanic and Atmospheric Administration scientist Gregory Johnson, Janet Sprintall of the Scripps Institution of Oceanography in San Diego and Volker Mohrholz from the Institute for Baltic Sea Research in Warnemunde, Germany, appears in the journal Science.
海洋沙漠化擴大中
'Ocean deserts' are growing
Low-oxygen regions have expanded over the past half-century.
1 May 2008, Nature, Michael Hopkin
http://www.nature.com/news/2008/080501/full/news.2008.795.html?s=news_rss
 |
| Warm waters: climate change models predict an expansion of oxygen-poor water. |
The discovery concerns a layer of the ocean called the 'oxygen-minimum zone', where concentrations of dissolved oxygen are particularly low. The new study shows that this zone has been expanding both upwards and downwards into the adjacent layers in tropical waters.
Climate models predict that warming of the sea's surface as a result of human activity will hamper the mixing of oceanic waters, preventing dissolved oxygen from mixing evenly through the water column. The new results suggest that this process has already begun.
Researchers led by Lothar Stramma of the University of Kiel, Germany, measured the oxygenation of the oceans at depths of between 300 and 700 metres during a series of observation cruises in tropical regions of the world's three main oceans. They added their new data to previous oxygen measurements to build up a picture of the trend over the past 50 years.
Overall levels of oxygen have dropped in these zones, Stramma and his colleagues report in Science 1. Regions of the eastern tropical Pacific Ocean and the northern reaches of the Indian Ocean are now classed as 'suboxic', meaning that the amount of oxygen has dropped sufficiently to harm the functioning of ecosystems.
Starving waters
In suboxic waters, nitrogen cannot react with oxygen to form biologically available nitrate. This means that organisms at the base of food chains, such as plankton, do not get enough nutrients to survive, Stramma explains.
The ultimate effect on commercially important ecosystems such as fisheries are difficult to predict, Stramma adds. "There are many complicated mechanisms involved that we need to understand better to predict changes for the future," he says. "I see our results as a starting point to be able some day to tell what changes in biogeochemistry, biology and fisheries we have to expect."
Any effect on fisheries is likely to be indirect, because these low-oxygen zones are far from the coastal waters that host most commercial fishing, suggests Andrew Solow, director of the Marine Policy Center at Woods Hole Oceanographic Institution in Massachusetts. "I don't know many fisheries that take place between 300 and 700 metres in the tropical ocean," he says.
These 'underwater deserts' should not be confused with the 'dead zones' created in coastal waters, most famously in the Gulf of Mexico, by runoff of nitrogen-rich fertilizer, Solow adds. Coastal waters lose their oxygen as a result of booms in phytoplankton growth; when these organisms die, they provide food for microbes that suck up all of the oxygen.
Going down
"It's a worrying trend," comments Laurence Mee, director of the Marine Institute at the University of Plymouth, UK. "This is one more piece in the argument that we need to do something about climate change."
Mee agrees that it's quite difficult to say whether, or how much, the decline in oxygen levels will affect ecosystems, including economically important ones. If the low-oxygen zones extend closer to the surface, they may reach the shallow, sunlit waters where many valuable fish species live. "When you start to mess around with the food chain, it has all kinds of knock-on effects that we don't know about yet," Mee says.
Team member Gregory Johnson of the National Oceanic and Atmospheric Administration in Seattle says that he and his colleagues now plan to take more measurements, to see whether the low-oxygen zones are spreading across the oceans, or spreading upwards and downwards within the water column.
當我們的海洋變酸
When our oceans turn sour
April 21, 2008, Ross Allen and Anthony Bergin
http://www.theage.com.au/news/opinion/when-our-oceans-turn-sour/2008/04/20/1208629730189.html
CLIMATE change is a core issue on the Rudd Government's agenda. But there's another carbon problem that has been avoided and is largely independent of global warming.
In a speech to the Australian Strategic Policy Institute last week on Australia's focus on the Pacific, parliamentary secretary for Pacific Island affairs Duncan Kerr pointed to the effect of marine acidity on coral reefs, the backbone of economic activity for many islander communities. Kerr noted that if land drowns and coral reefs die, the Pacific faces mass movements of people, presenting strategic and humanitarian challenges for Australia.
Confronting the profound problem of acid oceans that could devastate ocean life would demonstrate the Government's commitment to communities dependent on coastal resources in Australia, the Indian Ocean and South Pacific, as well as dealing with long-term global change.
Rising levels of carbon dioxide in the Southern Ocean are alarming scientists concerned about the productivity of oceans. As human activity introduces increasing amounts of carbon dioxide into the atmosphere, the ocean becomes more acidic.
The Southern Ocean is particularly important, because it is efficient at absorbing carbon dioxide from the atmosphere: it is here that the first effects are being felt.
Under conditions of increasing acidification, parts of the oceans will progressively become uninhabitable for certain types of plankton, the earth's most important life forms, and coral structures.
Some shell-forming species will struggle to reproduce vital shell structures and skeletons, which will have a direct effect on the ocean food web. Some species will decline, some will be displaced or will disappear and patterns of fisheries will change. Coral reefs, such as the Great Barrier Reef, will also suffer. Coral skeletons will become weaker and growth rates will reduce, leading to a significant decline by the middle of this century. This will deprive parts of our coastline of a natural protective barrier against the ocean, leading to greater threats from storm activity.
Similarly, environmental threats to states in our region with extensive coastal exposure will increase, resulting in more demands on Australia to assist Pacific Island countries with environmental disasters.
The size and global circulation of the oceans restrict the option of a preventive solution to acidification — such as adding ground limestone. So we need to learn how to adapt.
The Government has an opportunity to strengthen its environmental credentials by addressing the problem of ocean acidification.
There are four initial steps we should take.
First, we need a more collaborative national research effort. The current arrangement of loosely associated research institutions lacks the funding and co-ordination to develop an accurate national assessment of the problem.
Second, we need to address our marine research capability. Australia has only two major research platforms and both vessels are approaching the end of their useful lives. We have less capacity than many of our neighbours and are barely on par with New Zealand. As a stopgap measure we could use merchant vessels to begin a national monitoring program by collecting water samples.
Third, Australia should
take the lead in monitoring acidification levels in regional waters, especially in the Southern Ocean, and raise the issue of how to sustain our oceans at every opportunity in international bodies.
Many of our regional neighbours depend on coral reefs for tourism, and fish stocks in South-East Asia support some 20 million people. Acidification is therefore likely to generate increased calls for our development assistance.
And finally our security decision-makers need to factor ocean acidification into longer-term national risk assessments. Talking directly to Australia's marine science experts would be a sound place to start.
We have a larger stake in this issue than most countries. We are an oceanic superpower, with the third largest area of offshore marine estate in the world. Australian fisheries generate $2 billion in revenue and the Barrier Reef supports a $6.9 billion industry. And we are close to the Southern Ocean: the chilly waters to our south are the principal means for pumping carbon dioxide out of the atmosphere. That's where the warning bells are ringing.
As the planet warms, there will be winners and losers, but with acidification there are only losers. The need to understand the processes and manage this potential peril is getting more urgent.
Ross Allen and Anthony Bergin are researchers at the Australian Strategic Policy Institute.
酸的海洋可能是浮游生物的生命之水
Acidic oceans may be water of life for plankton
18 April 2008, NewScientist.com news service, Kate Ravilious
http://environment.newscientist.com/channel/earth/climate-change/dn13735-acidic-oceans-may-be-water-of-life-for-plankton.html?feedId=climate-change_rss20
Most life in the ocean will suffer as carbon dioxide levels increase and the water becomes more acidic. Some plankton will buck the trend, however, thriving and putting on weight as carbon dioxide levels rise – but it remains to be seen how this will affect the global carbon balance.
Débora Iglesias-Rodríguez, from the National Oceanography Centre at the University of Southampton, UK, and her colleagues, simulated the increase in dissolved carbon dioxide in surface ocean waters by bubbling carbon dioxide through cultures of coccolithophores, a type of single-celled photosynthesising plankton.
In previous experiments water acidity had been regulated by simply adding acid or base, but this method has been criticised for being too artificial. Iglesias-Rodríguez's method found that higher carbon dioxide concentrations increased calcification, speeding up growth of the tiny calcite plates on the plankton cell.
Carbon storage
Coccolithophores appear to benefit in two ways. The extra carbon dioxide aids photosynthesis, while the more acidic waters increase the concentration of bicarbonate – the main ingredient for coccolith plates, known as liths. Making the liths results in the release of carbon dioxide, but when dead plankton fall to the ocean floor the organic matter in their bodies can end up locked away in deep ocean sediments.
"Increased bicarbonate appears to stimulate an increase in mass of calcium carbonate produced by each coccolithophore cell," says Paul Halloran, a co-author from the University of Oxford.
The team's result is not confined to the lab. By studying fossil coccolithophores from a deep ocean core, they found that there has been a 40% increase in average coccolith mass over the last 220 years, mirroring the rise in carbon dioxide levels.
Other scientists think the results make sense and help to explain how coccolithophores survived the last rapid global warming event – the Palaeocene-Eocene thermal maximum 56 million years ago.
Cocco and insensitive
"Coccolithophores seemed to sail through the surface water acidification then, so perhaps they are quite insensitive to this kind of change," says Paul Bown from University College London.
As yet it isn't clear how these super-sized coccolithophores will affect the global carbon balance. If the oceans become too acidic, the shells of dead plankton will dissolve and release their carbon before they fall to the ocean floor.
"We can't yet be confident that stimulating plankton production will draw down carbon dioxide," says Bown.
隨著全球暖化，海洋沙漠化擴大
Ocean "deserts" expand with global warming
March 5, 2008
http://blog.seattlepi.nwsource.com/environment/archives/133510.asp
Increased carbon dioxide emissions are not kind to the world's oceans. It makes them more acidic, potentially dissolving some types of marine life. It makes them warmer, killing coral and sending mobile creatures on a search for cooler water. And now it seems that it's expanding "deserts" where there's less life.
Researchers with NOAA (National Oceanic and Atmospheric Administration) are reporting in the journal Geophysical Research Letters that areas of low productivity -- i.e. less plant life -- increased 15 percent from 1998 and 2007. That's an increase of 6.6 million square kilometers in the Pacific and Atlantic Oceans. The expansion lines up with an increase in the ocean surface temperature of approximately .02 to .04 degrees Celsius a year.
The science at work is pretty straightforward. As the surface of the water warms, it becomes more stratified (imagine it like a cake -- upper layer warm water, lower layer cold water). That prevents the colder, nutrient rich water from mixing with the upper layers. Without the nutrients, there's nothing to feed algae that help sustain other marine life.
The researchers did offer a caveat as regards the long-term trend, as taken from a NOAA press release:
"The fact that we are seeing an expansion of the ocean's least productive areas as the subtropical gyres warm is consistent with our understanding of the impact of global warming. But with a nine-year time series, it is difficult to rule out decadal variation," said Jeffrey J. Polovina, an oceanographer with NOAA's National Marine Fisheries Service in Honolulu, who authored the study along with NOAA's Evan A. Howell and Melanie Abecassis of the University of Hawaii.
These barren areas are found in roughly 20 percent of the world's oceans and are within subtropical gyres -- the swirling expanses of water on either side of the equator.
The desert was measured using NASA's orbiting SeaStar spacecraft and a sensor that measures the density of chlorophyll in phytoplankton, or algae.
