Researchers determine why the ocean has absorbed more carbon over the past decade

February 8, 2017 by Julie Cohen, University of California - Santa Barbara
A composite image of the Western hemisphere of the Earth. Credit: NASA

With the ocean absorbing more carbon dioxide (CO2) over the past decade, less of the greenhouse gas is reaching the Earth's atmosphere. That's decidedly good news, but it comes with a catch: Rising levels of CO2 in the ocean promote acidification, which breaks down the calcium carbonate shells of some marine organisms.

The cause of this recent increase in oceanic CO2 uptake, which has implications for , has been a mystery. But new research from UC Santa Barbara geographer Timothy DeVries and colleagues demonstrates that a slowdown of the ocean's overturning circulation is the likely catalyst. Their findings appear in the journal Nature.

"Such a slowdown is consistent with the projected effects of , where warming and freshening of the surface ocean from melting ice caps leads to weaker ," DeVries explained. "But over the time periods we studied, it's not possible to say whether the slowdown is related to natural climate variability or to climate change caused by human activity."

DeVries and fellow researchers Mark Holzer of the University of New South Wales in Sydney and François Primeau of UC Irvine compiled existing oceanographic tracer data—measurements of temperature, salinity, CFCs (manmade gases that dissolve into the ocean) and carbon-14—and separated it into three decade-long time periods: the 1980s, the 1990s and the 2000s.

Subsequent computer analysis of that data enabled the researchers to characterize —the transfer of water from the surface to the deep ocean and back again—for each time period. They then analyzed ocean-atmosphere carbon exchange and ocean carbon cycling within their circulation model.

"As the circulation changed from decade to decade —1980s to 1990s to 2000s—the model predicted a big dip in oceanic CO2 uptake during the 1990s, then a large increase in uptake during the 2000s," DeVries explained. "Furthermore, these swings were attributed directly to the changes in ocean circulation."

According to DeVries, this finding may seem counterintuitive. Prevailing scientific wisdom asserts that the deceleration of circulation diminishes the ocean's ability to absorb anthropogenic CO2 from the atmosphere as surface waters warm and become saturated with CO2.

"While that is true, there is another effect that appears to be more important in the short term," DeVries said. "The weaker overturning brings less naturally CO2-rich deep waters to the surface, which limits how much of that gas in the deep ocean escapes to the atmosphere. That causes the to absorb more CO2 from the atmosphere."

Explore further: Atlantic Ocean's slowdown tied to changes in the Southern Hemisphere

More information: Tim DeVries et al, Recent increase in oceanic carbon uptake driven by weaker upper-ocean overturning, Nature (2017). DOI: 10.1038/nature21068

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31 comments

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CCMcCombs
4 / 5 (1) Feb 08, 2017
The ocean is a tremendous buffer and directly impacts global climate. More basic research is needed into the interactions within the ocean and how energy is distributed. There is a ton of decadal and and multidecadal oscillations and natural variability going on that is very difficult to tease out of short term datasets.
Paulw789
2 / 5 (11) Feb 08, 2017
The total Carbon store in the oceans is about 39,000 billion tons Carbon.

The total net uptake since 1750 is only about 150 billion tons. 0.4% increase. Is this amount going to change anything?
unrealone1
1.5 / 5 (8) Feb 08, 2017
Jurassic period was 3000 ppm CO2
Man made CO2 in the atmosphere is 3% or 0.0012 correct?
Just how does that affect the ocean?
antigoracle
1.3 / 5 (13) Feb 08, 2017
The Pathological LIES of the AGW Cult and their Pathological FAKE "science".
http://www.treehu...ide.html
luisruiz1
4.6 / 5 (13) Feb 08, 2017
The total Carbon store in the oceans is about 39,000 billion tons Carbon.

The total net uptake since 1750 is only about 150 billion tons. 0.4% increase. Is this amount going to change anything?


That total of 39,000 billion tons may not take into account the effects it has on the aquatic ecosystems. CO2 + water would form carbonic acid so while the ocean can suck up that much carbon, how long before the acidity increases to toxic levels?
ddaye
2.8 / 5 (11) Feb 08, 2017
how long before the acidity increases to toxic levels?


Toxic to what? And toxic over what length of time? I've been seeing reports in the general public science news of negative effects in some species already.
ddaye
2.2 / 5 (9) Feb 08, 2017
Jurassic period was 3000 ppm CO2
Man made CO2 in the atmosphere is 3% or 0.0012 correct?
Just how does that affect the ocean?

Oceanographers would be the ones to ask that question.
My question is: which ocean? The Jurassic ocean whose planet supported no mammals much larger than rats, or our ocean whose planet supports a finely tuned just-in-time economy of 7 billion humans?
rrrander
1.4 / 5 (11) Feb 08, 2017
If the greenloons are concerned about ocean or other acidification, why were the proposing to dump megatons of sulfur particles into the atmosphere, which would result in huge acidification of land and water? Global warming, the biggest wealth-redistribution con since communism.
Pumastar
5 / 5 (11) Feb 09, 2017
If the greenloons are concerned about ocean or other acidification, why were the proposing to dump megatons of sulfur particles into the atmosphere, which would result in huge acidification of land and water? Global warming, the biggest wealth-redistribution con since communism.


Using dumb one liners to justify why YOUR fossil fuel fratteny destroys the air we breath and the animals in the sea doesn't make you look good, it just exposes who you are, how you think, how selfish you are, and how little you care for the world.
HeloMenelo
4 / 5 (10) Feb 09, 2017
The Pathological LIES of the AGW Cult and their Pathological FAKE "science".
http://www.treehu...ide.html


aaaa Monkey quoting links he can't read nor understand, because putting it all together to get the bigger picture never was one of his strong points, and never will be, keep swinging those trees, we'll keep on throwing you the bananas ;)
Pumastar
5 / 5 (10) Feb 09, 2017
Lot's of stupid comments getting 1 out of 5s as usual, looks like the denier crazies is on a banana spree again.
FactsReallyMatter
1 / 5 (13) Feb 09, 2017
Ahemm, the ocean is base with a current ph in the 8.1 range.

Framing this topic in terms of increasing acidification is simply an attempt to mislead readers.

At the current rate of 0.1 drop every 200 years, guess how long it will be before the ocean is simply neutral?? Assuming that this rate continues, which as this paper suggests it will slow down.

novaman
5 / 5 (9) Feb 09, 2017
Ahemm, the ocean is base with a current ph in the 8.1 range.

Framing this topic in terms of increasing acidification is simply an attempt to mislead readers.

At the current rate of 0.1 drop every 200 years, guess how long it will be before the ocean is simply neutral?? Assuming that this rate continues, which as this paper suggests it will slow down.


Here Numb nuts antigoricle sock once again shows us his complete and utter misunderstanding a drop in PH does not mean a drop in acidity monkey nuts.
Ocean life can be sensitive to slight changes in pH levels, and any drop in pH is an increase in acidity, even in an alkaline environment.
The acidity of global surface waters has increased by 30% in just the last 200 years. This rate of acidification is projected through the end of the century to accelerate even further with catastrophic impacts to marine ecosystems.
HeloMenelo
4.2 / 5 (10) Feb 09, 2017
factdoesn'tmatter antigoricle sock framed himself...again, misleading his socks to stupidity, yet again.
antialias_physorg
4.9 / 5 (13) Feb 09, 2017
The total Carbon store in the oceans is about 39,000 billion tons Carbon.

The total content is completely irrelevant. The only relevant thing here is the ability to take in more (i.e. the size of the buffer the oceans provide). Relying on filling up a buffer is never a good idea, because eventually a buffer becomes full - and then things change in a *real* hurry.

Ahemm, the ocean is base with a current ph in the 8.1 range.

Framing this topic in terms of increasing acidification is simply an attempt to mislead readers.

Erm no, because readers (unlike you) have gone to school and sat in on chemistry class. They know the difference between acidic and acidification.
Whether the ocean has a neutral pH or not is completely irrelevant. The *change* is what's relevant.

At the current rate of 0.1 drop every 200 years, guess how long it will be before the ocean is simply neutral?

Geez. You don't even know pH is a log scale? Get some education. Please.
FactsReallyMatter
1.8 / 5 (15) Feb 09, 2017
Oh, please - like statements such as "increased acidification" aren't meant to alarm the public into thinking we have already have an acid ocean and the water is eating the poor fishies alive. That is precisely the message the AGW cult want to spread. Come back to earth already! Wait, no it is better for you to stay off planet.

Plus, I missed the part where you tell me when the ocean becomes acidic. Please make that prediction!

How did the oceans ever survive in the past, when CO2 was in the 1000's ppm?

If you can stop licking my socks for a second, you might answer but I don't expect any sense from this crowd.
humy
4.7 / 5 (14) Feb 09, 2017
Ahemm, the ocean is base with a current ph in the 8.1 range.

Framing this topic in terms of increasing acidification is simply an attempt to mislead readers.

At the current rate of 0.1 drop every 200 years, guess how long it will be before the ocean is simply neutral??

FactsReallyMatter

You ignorant moron; ocean acidification means a DECREASE in PH, NOT the ocean water literally turning to acid.

https://en.wikipe...fication
"...Ocean acidification is the ongoing DECREASE in the pH of the Earth's oceans,
...
Seawater is slightly basic (meaning pH > 7), and the process in question is a SHIFT TOWARDS pH-neutral conditions RATHER THAN a transition to ACIDIC conditions (pH < 7).
" (my emphases)

I learned this at school even before I went to university.
Study some of the science before shouting your ignorant mouth off about climate science or any other kind of science.
HeloMenelo
4.2 / 5 (10) Feb 09, 2017
blablabla...

Plus, I missed the part where you tell me when the ocean becomes acidic. Please make that prediction!

How did the oceans ever survive in the past, when CO2 was in the 1000's ppm?

If you can stop licking my socks for a second, you might answer but I don't expect any sense from this crowd.


This clown (an antigoracle sock) seems to miss a lot of parts, i bet his also skips a few branches swinging trees slamming into the trunks, we don't need to lick your socks, as you lick your own SOCKpuppets basckside's here everyday to promote your idiocy. We just sit back and laugh with the rest of the world.
HeloMenelo
4.2 / 5 (10) Feb 09, 2017

I learned this at school even before I went to university.
Study some of the science before shouting your ignorant mouth off about climate science or any other kind of science.

This antigoracle monkey sock name cracked me up, "reacfactsmatter" while in the real world, he did not even pass primary school lol
antialias_physorg
4.5 / 5 (16) Feb 09, 2017
Plus, I missed the part where you tell me when the ocean becomes acidic

Since that is completely irrelevant to what the article is talking about (or anything else for that matter) - what's your point?

Chemistry works like this: Even in water with a pH of more than 7 you have free H+ ions (which is what the pH value measures in the first place, you know?). I.e. even in a base solution of pH greater than 7 you have acidic reactions. shift the pH downwards and the reactions increase.

Man, what do they teach in US schools? This is like the first thing you should have learned in chemistry class.


How did the oceans ever survive in the past, when CO2 was in the 1000's ppm?

Mass extinction of foraminifera was the result during the Paleocene–Eocene Thermal Maximum. They are part of the base of the food chain - i.e. important to support the fish populations we rely on for food.
gkam
3.3 / 5 (12) Feb 09, 2017
Deniers can't really believe their stuff. The science is pretty clear about it.

I think these are the "WMD!" folk again. They assume we are all subject to the simple emotional manipulation used against them. But our educations in science prevent that.
RealScienceMatter
4.3 / 5 (12) Feb 09, 2017
bleee blaaa blooo
Still waiting for someone educated enough to postulate something besides one instance of elevated CO2 coinciding with one oceanic mass extinction event...when there are no other examples. Part of a science education is supposed to be honing the ability to critically assess information that is stated as fact and the conclusions made based upon said facts.

I have read countless of Scienctific findings on this site the past month and it seems that
Facts showed that YOU can't be educated, YOU throughout the years have been shown decades of scientific FACTS that PROVE climate change, but it goes in the one ear bounces in the hollowness inside and out the other ear.
HeloMenelo
4.6 / 5 (9) Feb 09, 2017
Bleee blaaa blooo
I have read countless of Scienctific findings on this site the past month and it seems that
Facts showed that YOU can't be educated, YOU throughout the years have been shown decades of scientific FACTS that PROVE climate change, but it goes in the one ear bounces in the hollowness inside and out the other ear.

"But nonetheless still can't answer the simple question, so I will resort to a personal attack to display my intelligence"....
Funny that Blee Blaaa blooo is the smartest thing you said. Who is your tutor, the cash me ousside girl?

You haven't earned any answers, as YOU cannot back any of your 1000s of lies on this site throughout decades, not a single ONE. Not ONE. You have proven your inability to understand Science over and over and clearly have shown your incompetency. YOU want answers monkey boy, start backtracking to the very beginning and provide US with Real Scientific Proof every single lie you preached. Earn it !
HeloMenelo
4.1 / 5 (9) Feb 09, 2017
YOU throughout the years have been shown decades of scientific FACTS that PROVE climate change,

Pssst...the one sure thing about the climate is that it changes, nobody is denying that....the article is about the claims of ocean acidification as a result of increased CO2 and the "dire" consequences of it, hence the very valid question it seems only one person tried to answer...which was done in a way that resulted in more questions if the answer is valid. It seems some here cannot dialogue any further than stating their opinion and personally attacking anyone who disagrees with it.

O yes you are denying Human Induced Climate change Monkey Goracle sock, so there's goes your dandy little o i'm so scared don't insult me little attitude.

Second your insults though dumb, stupid and always self inflicting, is spreaded throughout thousands of comments on this site, so that's a double whammy monkey boy, have another banana ;)
RealScienceMatter
4.2 / 5 (10) Feb 09, 2017
Oop... seems like bscot's got a long history of lies,false claims and trolling on this site, thanks helo :)
gkam
2.3 / 5 (6) Feb 10, 2017
Insults aside, we are in for truly worrisome times ahead. The acidification of the seas may result in a Soylent Green environment.

But we are opposed by those whose positions are determined by political prejudice and fear of losing business. They have the money and Big Mouths. They will lose the argument, as we are overcome with the disasters ahead of us. But all of us will lose.

Bigly.
richdiggins
2.3 / 5 (6) Feb 10, 2017
@bschott
Good luck trying to have an intellectual conversation on this site, especially regarding AGW. These kids will not back down from their indoctrination.

I agree with you that geological records tell a different story.
antialias_physorg
5 / 5 (7) Feb 10, 2017

I agree with you that geological records tell a different story.

Well then you don't seem to have grasped the difference between geological timescals and the timescales we are currently dealing with.

For the intellectually challenged here's a graph (to scale) of the difference in speed we're dealing with
https://xkcd.com/1732/

I especuially like the mouse-over text

"(after setting your car on fire). Listen: your car's temperature has changed before"

That's really the kind of idiotic arguments the deniers are making.
FactsReallyMatter
1.8 / 5 (5) Feb 13, 2017

Well then you don't seem to have grasped the difference between geological timescals and the timescales we are currently dealing with.


Actually, I do - and trying to make predictions based on the very, very short timescale that the AGW crowd is trying to fearmonger in and based on the very, very limited set of actual data that is of any relevant accuracy is an exercise in futility.

gkam
2 / 5 (4) Feb 13, 2017
Why do folk who worship money assume we all make our decisions based primarily on that?

Many of us have other values.
antialias_physorg
5 / 5 (2) Feb 13, 2017
Actually, I do

If you doid you wouldn't have made the 'argument' you tried (and failed) to make.

and based on the very, very limited set of actual data that is of any relevant accuracy

Are you mental? The amount of data collected is huge. Did you miss the past decades of climate research completely?

Geez, man - you already demonstrated that you didn't attend chemistry class. Now you demonstrate that you didn't attend math class.

What exactly did you do in school? Smoke weed?

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