Southern Ocean Carbon Sink Weakened About 15% Per Decade Since 1981
19 May 2007
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| The Southern Ocean. Source: CIA Factbook 2007 |
Scientists have observed the first evidence that the Southern Ocean’s ability to absorb carbon dioxide has weakened by about 15% per decade since 1981.
In research published in the journal Science, an international research team concludes that the Southern Ocean carbon dioxide sink has weakened between 1981 and 2004 by 0.08 PgC/y per decade relative to the trend expected from the large increase in atmospheric CO2. The consequences of this include a reduction in the efficiency of the sink in the short term (about 25 years) and possibly a higher level of stabilization of atmospheric CO2 on a multicentury time scale.
The Southern Ocean is the circumpolar body of water around the continent of Antarctica and extending up to 60 degrees south latitude. The Southern Ocean is the fourth largest of the world’s five oceans (after the Pacific Ocean, Atlantic Ocean, and Indian Ocean, but larger than the Arctic Ocean).
The researchers found that the Southern Ocean is becoming less efficient at absorbing carbon dioxide due to an increase in wind strength over the Ocean, resulting from human-induced climate change. The increase in wind strength is due to a combination of higher levels of greenhouse gases in the atmosphere and long-term ozone depletion in the stratosphere, which previous CSIRO research has shown intensifies storms over the Southern Ocean.
—Dr Paul Fraser, CSIRO Marine and Atmospheric Research
The increased winds influence the processes of mixing and upwelling in the ocean, which in turn cause an increased release of carbon dioxide into the atmosphere, reducing the net absorption of carbon dioxide into the ocean.
This is the first time that we’ve been able to say that climate change itself is responsible for the saturation of the Southern Ocean sink. This is serious. All climate models predict that this kind of “feedback” will continue and intensify during this century. The Earth’s carbon sinks—of which the Southern Ocean accounts for 15%—absorb about half of all human carbon emissions. With the Southern Ocean reaching its saturation point more CO2 will stay in our atmosphere.
—Dr Corinne Le Quéré, University of East Anglia and British Antarctic Survey
The international team comprised researchers from CSIRO in Australia, the Max-Planck Institute in Germany, the University of East Anglia and British Antarctic Survey in England, the Climate Monitoring and Diagnostics Laboratory in the US, NIWA in New Zealand, the South African Weather Service, LSCE/IPSL and CNRS in France, and the Centre for Atmospheric and Oceanic Studies in Japan.
The team used observations from 40 stations around the world, including Cape Grim in north-west Tasmania. The Cape Grim station, operated by the Australian Bureau of Meteorology, monitors and studies changes in global atmospheric composition in a program led by CSIRO and the Bureau.
Resources:
“Saturation of the Southern Ocean CO2 Sink Due to Recent Climate Change”; Corinne Le Quéré, Christian Rödenbeck, Erik T. Buitenhuis, Thomas J. Conway, Ray Langenfelds, Antony Gomez, Casper Labuschagne, Michel Ramonet, Takakiyo Nakazawa, Nicolas Metzl, Nathan Gillett, Martin Heimann; Science Express DOI: 10.1126/science.1136188
I will wait until other research confirms these findings as they are somewhat counter intuitive. Dissolving any gas into a liquid like water is a function of temperature and stirring action.
Rising temperature allows the liquid to hold less absorbed gas. look at thee fizz of a glass of soda as it warms and goes flat and unfizzy as the CO2 is released.
Increased stirring which exposes more liquid gas interface area increases the ability to absorb dissolved gas.
This research DID NOT say that sea surface temperature in the Antarctic were rising. They would ahve if they had observed thsi to be happening. Rising temperature of the water expelled gas which would have the effect of artificially raising the atmospheric CO2 level. Remember that the Oceans have the capacity to store, and they do, all the CO2 in the atmosphere thousands of times over.
That is why even Al Gore concedes that atmsopheric CO2 levesl are seen to increase with a lag AFTER the world warms up. He says it "complex" why the historical record shows Cause (Warming) and Effect (more CO2) and not the other way around Effect first then Cause. Ball falls down before it decides to jump up into the air.)
The research purports to show that additional stirring by weather reduces rather than strengthens the amount of gas able to be dissolved. That is patent counter-intuitive nonsense. If true, then every aquarium in the world is stupid to bubble air into and through the liquid to increase the dissolved gasses in the water.
This is like the research that purported to prove that margarine was better than butter; than that margarine contained trans fats which were worse. The research that purported to show showed first green, then black, and orange teas were much better than all the others; than that there was no difference; coffee was bad and then OK; yada yada yada. N-O-N-S-E-N-S-E ...
Posted by: Stan Peterson | 19 May 2007 at 11:48 AM
That is patent counter-intuitive nonsense.
You tell em Stan!!
Could you explain the butter, margarine, CO2 connection again?? You lost me on that.
Posted by: DS | 19 May 2007 at 12:01 PM
Damn Stan, you can model the Southern Ocean carbon sink with a glass of club soda? If I bring over two lollipop sticks, a rubber band, and some crazy glue, could you show me how to model the stock market? That's some bomb ass MacGyver science man!
Posted by: yesplease | 19 May 2007 at 01:12 PM
Stan,
My intuition isn't working as well as yours. If you shake a bottle of soda while maintaining a constant temperature, it still fizzes.
In the future when we need more CO2 in the atmosphere, we can drop Mentos into the ocean.
Posted by: JMartin | 19 May 2007 at 02:34 PM
here's a link to another story on these findings which explains the carbon source a bit better.
http://www.abc.net.au/science/news/stories/2007/1926751.htm
Stan must be thinking about covering the oceans with manmade rafts of multi-coloured tea crops to absorb all that man-made carbon.
Posted by: aussie paul | 19 May 2007 at 04:34 PM
Stan, most anyone with a scientific background recognizes that the Earth's climate and weather is a complex linked system with a lot of feedback. Such systems exist everywhere in the world from climate, to our own physiology, to economics. A system which has purely linear feedback relationships can be analyzed mathematically. Unfortunately, a lot of real world systems such as climate are highly complex and highly nonlinear, making them intractable to solve as a set of equations. We thus have to develop models and try to simulate the behavior of the system. When scientists, mathematicians and engineers study such systems, we realize there are severe limitations to how far intuition will get one.
In our Earth's climate CO2 and temperature both affect each other... in this case with several feedback mechanisms, such as Southern Ocean effect just described, that are positive feedback. Positive feedback, while nice to receive as a person, is not what you want a lot of in systems like the climate. Positive feedback like this, warming begets CO2 and CO2 begets warming, causes the system to go unstable until some other mechanism kicks in and the system regains stability... but often it is in a vastly different state than where it started.
I prefer my Earth stable, if you please.
Posted by: rhapsodyinglue | 19 May 2007 at 06:08 PM
Earth's history includes ice everywhere and ice nowhere. Wild swings over time. I'm still not convinced we are affecting it one iota. It is doing what is always has done. It's own thing.
You may prefer a stable earth. Dreaming is part of being human.
Posted by: Rick | 20 May 2007 at 10:10 AM
Rick, you failed to mention the rate at which Earth's temperature or CO2 levels vary over time, over its history.
Would you comment on your inclination to believe that the present rate of change of avg temp or atmospheric CO2 concentration, is much faster than anything indicated in the historical record?
Thanks! Regards,
Shane
Posted by: Shane | 20 May 2007 at 03:18 PM
Shane,
Temperature and CO2 changes are only much wilder than anything over the last 700,000 years, as explained by ice core data.
There have probably been wider swings caused by major asteroid impacts, which have led to mass extinctions.
Posted by: Alex | 20 May 2007 at 03:56 PM
I'm not totally convinced of anything. I expect consensus science to come out with something entirely different to explain global warming in the next 10 years.
The sun, natural methane, cosmic rays - who knows?
Or maybe the numbers will change and we'll be warned about the coming chill again.
I know it doesn't count for anything, but here in Vancouver we've had a cold winter, a cold spring and are expecting a cool summer. It's hard to worry about global warming when you're shivering all the time.
Posted by: Rick | 20 May 2007 at 06:30 PM
“They analyzed data from 11 monitoring stations that measured carbon-dioxide concentration just above the surface of the water. The data covered 1981 to 2004.
Using those readings, researchers estimated how much carbon was being absorbed by the water.
They estimated that the Southern Ocean absorbed 0.6 billion metric tons of carbon in 1981. At the same time, it released 0.3 billion metric tons that had been stored in the ocean, for a net absorption of 0.3 billion metric tons.
By 2004, the ocean was taking in 0.8 billion metric tons of carbon but spitting out 0.5 billion metric tons. The total net amount of carbon absorbed was the same.
But researchers then compared the results with computer predictions of what the ocean should have absorbed given rising atmospheric carbon-dioxide levels. In 2004, the net absorption should have been 0.5 billion metric tons, the report said.
The findings are controversial. Pieter Tans, a senior scientist at the National Oceanic and Atmospheric Administration in Boulder, Colo., said the measurements of carbon-dioxide changes were so subtle that they could have been sampling errors.”
http://seattletimes.nwsource.com/html/nationworld/2003712141_ocean18.html
Apparently, presented numbers (0.3, 0.5, 0.8 BtC) are calculated only for “antropogenic” carbon emissions, which are about 5 BtC yearly. World oceans do not distinguish between “antropogenic” or “natural” CO2 in atmosphere, and oceans exchange yearly more than 90 GtC with atmosphere (90 in 92 out), and 15% of this number for South Ocean is 13.5 BtC:
http://en.wikipedia.org/wiki/Carbon_cycle
Which makes difference of 0.2 BtC about 1.5% of total flux, arguably within sampling and estimating errors.
As usual, more research is needed.
Posted by: Andrey | 20 May 2007 at 09:09 PM
Eat,drink and be merry for tomorrow we die.I think much of the public is going to hear from these reports that no matter what we do its to late.We killed the planet.Game time.
Unfortunately,after having made the sale enviros keep trying to scare the crap out of people.They better adopt a more positive"we can turn this around" message or peeps are going to feel that die has been cast and its time to party and fashion a golden calf.
Posted by: Earl | 21 May 2007 at 04:10 AM
I always wonder why when we knew mother nature has clumate shifts everyone was shocked when we find the gearshift.. I amkust hoping mother nature has a speed li,iter and not a twin turbo with nitro boost...
Posted by: wintermane | 21 May 2007 at 05:21 AM
If the current scientific consensus is correct - the die has been cast. Our wimpy efforts to reduce green house gasses are laughable. Just laughable. Even in the enlightened west we are increasing ghg. We're a society of people little better than Travolta with his fleet of private jets and his efforts to do his bit - whatever that means.
And don't the developing world. That is the real story. The coal is getting burned faster and faster. There is no turning around this ship. It's a done deal.
There are only two realistic hopes.
1 - that the consensus science is off and the planet can make it's own compensations.
2 - that this whole global warming thing won't be so bad after all.
But forget the turning it around talk - that only happens when the coal runs out.
Posted by: Rick | 21 May 2007 at 08:00 AM
This is really scary news folks.
The world’s oceans are one of two main carbon ’sinks’ - absorbers of carbon dioxide from the atmosphere, that in the natural carbon cycle help keep greenhouse gas levels in the atmosphere in check. As we destabilize the natural carbon cycle with man-made greenhouse gas emissions, we cause global warming which in turn is expected to weaken the ability of the oceans to absorb carbon dioxide, leading to a further buildup of atmospheric carbon dioxide levels, driving further warming. This is just one of many powerful feedback mechanisms that could push climate change beyond our ability to halt.
Climate models and the IPCC reports take this feedback into account, but generally do not assume it will kick in until mid-century. If the ability of the world’s oceans to absorb carbon dioxide is already beginning to decrease, we will need to recalculate the speed and severity at which the world must cut greenhouse gas emissions in order to stabilize the climate and avoid disastrous climate change.
It’s definitely time to get serious about cutting greenhouse gas emissions as hard and as fast as possible. And the United States needs to lead the way. We need to begin a bold plan to cut emissions as quickly as possible by the end of the next decade, perhaps by 30-60 percent, levels even greater than the supposedly ‘gold standard’ Sanders-Boxer Global Warming Pollution Reduction Act proposes (it calls for about a 15% cut by 2020).
When we read news like this, it’s clear that time is definitely running out!
Posted by: JesseJenkins | 21 May 2007 at 08:36 AM
Given the high stakes associated with climate change and environmental pollution / destruction, it's amusing to me we're even debating this crap. Yeah it might all be BS, but our very best scientific minds are warning us that things aren't cool and that things need to change FAST. We can't keep pissing on the planet as assume that she'll continue to support us. Something the men who run our nations and multinational companies seem to fail to understand is that Nature bats last. And if she bats hard, we're all f*cked.
Posted by: Chillpill | 21 May 2007 at 12:10 PM
Wait until the tundra and permafrost melt and give off methane, which is 20 times more potent a GHG than CO2. Then you will see a positive feedback loop that should rival all others.
Posted by: SJC | 22 May 2007 at 08:25 AM
rhapsodyingglue,
Yes certainly the systems may be linear or nonlinear. But Science teaches us to always consider first principles and these first principles must be observed.
Part of the problem is we are dealing with effects at the limits of our ability to measure. The changes and effects are very tiny.
The world's climate or temperature is barely measurable by our advanced Science, with the best measurement equipment available today. Inferring what it was at some time in the past, is even tougher; and more in the province of guesswork as the precision gets higher.
You may prefer a stable world, as do I. I prefer it as more than an aesthetic desire, as life needs it so. Life has always needed that, and Life is still here, so by and large the Earth climate has been stable; relatively.
But stability is relative. Stable with in 10%? 5%? 1%? .5%? .1%? .01%? Since 1760 the inferred "bottom" of the last cold period, the temperature has been inferred to increase less than 1 part in 273, or .0003. Trying to measure such a small amount is tough, especially when most experimental apparatus isn't accurate much more than a few percent of so.
If we weren't peering at this so closely we can make the argument that its unmeasurable and stable. We see still have not exceeded the temperatures that are inferred tot have occurred in Man's historical records. It is unlikely to happen even with the worst estimates before a few hundred years, so there is little danger. If mankind is responsible we will have stopped doing so in a but a few decades as we get less thumblefingered with our technology. OTOH if it is natural and therefor little we can do, at least it s better to be warmer than colder. Its easier to feed the world, in a warmer more fertile, more fecund world.
My references to other "research results" that were surprising but on further research proved to be wrong, has caused some concern. Ttiny effects at the margin of the ability to measure, almost always produce conflicting research. I was merely saying I would not be surprised to see this 'research' contradicted by other studies.
Posted by: Stan Peterson | 23 May 2007 at 03:04 PM
For daily updated news on biofuels, ethanol and climate change issues, please visit:
http://www.ethanol-news.de
Posted by: http://www.ethanol-news.de | 31 May 2007 at 03:26 AM