'Acidifying oceans' threaten food supply, UK warns

[April Kincaid]

'Acidifying oceans' threaten food supply, UK warns
By Richard Black
Environment correspondent, BBC News website, Copenhagen

Acidification of the oceans is a major threat to marine life and humanity's food supply, Hilary Benn is to warn as the UN climate summit resumes.

The UK environment secretary will say that acidification provides a "powerful incentive" to cut carbon emissions.

Ocean chemistry is changing because water absorbs extra CO2 from the air.

Some believe this could be as big an impact of rising CO2 levels as climatic change, though it is rarely discussed within the UN climate convention.

The UN summit in Copenhagen, which started a week ago, is scheduled to conclude on Friday, when more than 100 world leaders will attend in an effort to agree a new global treaty on climate change.

[April Kincaid]

Acidification of the oceans affects marine life

[April Kincaid]

OCEAN ACIDIFICATION
Up to 50% of the CO2 released by burning fossil fuels over the past 200 years has been absorbed by the world's oceans
This has lowered the pH value of seawater - the measure of acidity and alkalinity - by 0.1
The vast majority of liquids lie between pH 0 (very acidic) and pH 14 (very alkaline); 7 is neutral
Seawater is mildly alkaline with a "natural" pH of about 8.2
The IPCC forecasts that ocean pH will fall by "between 0.14 and 0.35 units over the 21st Century, adding to the present fall of 0.1 units since pre-industrial times"

Natural lab shows sea's acid path
What is ocean acidification?
'Coral lab' offers acidity insight

[April Kincaid]

'Really important'

The science has come to prominence only within the last five or six years, and most of the details were not available when the convention was signed in 1992.

"We know that the increasing concentration of CO2 [in the air] is making the oceans more acidic," Mr Benn told BBC News.

"It affects marine life, it affects coral, and that in turn could affect the amount of fish in the sea - and a billion people in the world depend on fish for their principal source of protein.

"It doesn't get as much attention as the other problems; it is really important."

In September, the UN-backed study into The Economics of Ecosystems and Biodiversity (Teeb) concluded that the widely-endorsed target of trying to stabilise atmospheric concentrations of CO2 or their equivalent to around 450 parts per million (ppm) would prove lethal to much of the world's coral.

[April Kincaid]

[April Kincaid]

1.
Up to one half of the carbon dioxide (CO2) released by burning fossil fuels over the past 200 years has been absorbed by the world's oceans

2.
Absorbed CO2 in seawater (H2O) forms carbonic acid (H2CO3), lowering the water's pH level and making it more acidic

3.
This raises the hydrogen ion concentration in the water, and limits organisms' access to carbonate ions, which are needed to form hard parts

[April Kincaid]

Mr Benn will be speaking during the summit's "oceans day" at a meeting organised by Stanford University and Scripps Institution of Oceanography, both based in California.

"Unlike global warming, which can manifest itself in nuanced, complex ways, the science of ocean acidification is unambiguous," said Andrew Dickson, a Scripps professor of marine chemistry.

"The chemical reactions that take place as increasing amounts of carbon dioxide are introduced to seawater have been established for nearly a century."
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Glossary in full

The oceans and atmosphere are constantly exchanging CO2.

Concentrations in the atmosphere are now about 30% higher than in pre-industrial times; a proportion of this is absorbed by seawater, which results in rising concentrations of carbonic acid.

As a result, the pH of seawater has fallen by about 0.1, and a further change of 0.3-0.4 is expected by the end of the century.

This is likely to affect the capacity of organisms including molluscs, coral and plankton to form "hard parts" of calcium carbonate.

A 2007 study showed that rates of coral growth on the Great Barrier Reef had fallen by 14% since 1990.

Mr Benn will say that the Intergovernmental Panel on Climate Change (IPCC) should investigate ocean acidification during its next major assessment of the Earth's climate, scheduled for release in 2013.

Richard.Black-INTERNET@bbc.co.uk

http://news.bbc.co.uk/2/hi/science/nature/8411135.stm

[Volitzer]

CO2 and H2O into Carbonic Acid !!!      What a load of $#!t.

If that were the case the exhaust pipe on your cars would need constant replacing cuz CO2 and H20 are byproducts of combustion.

More junk science to con the gullible an the clueless.

Plants convert CO2 and H2O to plant sugars.  It's called the Carbon Cycle.  No plants dying from Carbonic Acid poisoning.

Why are you so gullible ?  Is your latest boyfriend one of these environmentalists and you are trying to impress him ??

[Shonnon]

Volitzer, science has long since proven that an excess of CO2 traps heat in the atmosphere.

Where do you get your science from?  That is pretty basic.

[Shonnon]

As for the information printed above, that is also pretty basic to anyone who owns an aquarium and finds it overpopulated because of an excess of nitrate levels.

[Shonnon]

.

[Volitzer]

Volitzer, science has long since proven that an excess of CO2 traps heat in the atmosphere.

Where do you get your science from?  That is pretty basic.

Do you know that CO2 is only 0.6% that's 0.006 or 6/1000 of Earth's overall atmosphere.

CO2 and water is absorbed by plants to make plant sugar.

When sunspots are numerous the atmosphere temperature goes up on Earth, Mars and Saturn.

When the sunspots disappear the atmosphere temperature goes down on all planets and moons.

[Volitzer]

As for the information printed above, that is also pretty basic to anyone who owns an aquarium and finds it overpopulated because of an excess of nitrate levels.

CO2 and H20 would need some input of energy to make it carbonic acid.

It would be like taking water and CO2 and trying to synthesize gasoline from it.

Can it be done.  Sure.  However it is a reverse reaction and would require an input of energy.

[Shonnon]

Elevated CO2 levels contribute to additional absorption and emission of thermal infrared in the atmosphere, and contribute to net global warming.

[Shonnon]

This figure shows the history of atmospheric carbon dioxide concentrations as directly measured at Mauna Loa, Hawaii. This curve is known as the Keeling curve, and is an essential piece of evidence of the man-made increases in greenhouse gases that are believed to be the cause of global warming. The longest such record exists at Mauna Loa, but these measurements have been independently confirmed at many other sites around the world [1].

The annual fluctuation in carbon dioxide is caused by seasonal variations in carbon dioxide uptake by land plants. Since many more forests are concentrated in the Northern Hemisphere, more carbon dioxide is removed from the atmosphere during Northern Hemisphere summer than Southern Hemisphere summer. This annual cycle is shown in the inset figure by taking the average concentration for each month across all measured years.
The grey curve shows the average monthly concentrations, and red curve is a moving 12 month average.