Earth's oceans have absorbed 60 percent more heat than previously thought

October 31, 2018, Princeton University
Princeton and Scripps researchers report that the world's oceans absorbed more than 13 zettajoules -- which is a joule, the standard unit of energy, followed by 21 zeroes -- of heat energy each year between 1991 and 2016. That's 150 times more heat energy each year than the energy humans produce as electricity annually. The estimate is 60 percent higher than that used in the IPCC's Fifth Assessment Report. Credit: Abigale Wyatt, Princeton Department of Geosciences

For each year during the past quarter century, the world's oceans have absorbed an amount of heat energy that is 150 times the energy humans produce as electricity annually, according to a study led by researchers at Princeton and the Scripps Institution of Oceanography at the University of California-San Diego. The strong ocean warming the researchers found suggests that Earth is more sensitive to fossil-fuel emissions than previously thought.

The researchers reported in the journal Nature Nov. 1 that the world's oceans took up more than 13 zettajoules—which is a joule, the standard unit of energy, followed by 21 zeroes—of heat energy each year between 1991 and 2016. The study was funded by the National Oceanic and Atmospheric Administration and the Princeton Environmental Institute.

First author Laure Resplandy, an assistant professor of geosciences and the Princeton Environmental Institute, said that her and her co-authors' estimate is more than 60 percent higher than the figure in the 2014 Fifth Assessment Report on climate change from the United Nations Intergovernmental Panel on Climate Change (IPCC).

"Imagine if the ocean was only 30 feet deep," said Resplandy, who was a postdoctoral researcher at Scripps. "Our data show that it would have warmed by 6.5 degrees Celsius [11.7 degrees Fahrenheit] every decade since 1991. In comparison, the estimate of the last IPCC assessment report would correspond to a warming of only 4 degrees Celsius [7.2 degrees Fahrenheit] every decade."

Scientists know that the ocean takes up roughly 90 percent of all the excess energy produced as the Earth warms, so knowing the actual amount of energy makes it possible to estimate the surface warming we can expect, said co-author Ralph Keeling, a Scripps Oceanography geophysicist and Resplandy's former postdoctoral adviser.

"The result significantly increases the confidence we can place in estimates of ocean warming and therefore helps reduce uncertainty in the climate sensitivity, particularly closing off the possibility of very low ," Keeling said.

Climate sensitivity is used to evaluate allowable emissions for mitigation strategies. Most climate scientists have agreed in the past decade that if global average temperatures exceed pre-industrial levels by 2? (3.6?), it is all but certain that society will face widespread and dangerous consequences of .

The researchers' findings suggest that if society is to prevent temperatures from rising above that mark, emissions of carbon dioxide, the chief greenhouse gas produced by human activities, must be reduced by 25 percent compared to what was previously estimated, Resplandy said.

The researchers' results are the first to come from a measuring technique independent from the dominant method behind existing research, she said.

Previous estimates relied on millions of spot measurements of ocean temperature, which were interpolated to calculate total heat content. Gaps in coverage, however, make this approach uncertain. A network of robotic sensors known as Argo now makes comprehensive measurements of ocean temperature and salinity across the globe, but the network only has complete data going back to 2007 and only measures the upper half of the ocean. Several reassessments of heat content have been made in recent years using the ocean-temperature data—including the recent Argo data—which has led to upward revisions of the IPCC estimate. 

Resplandy and her co-authors used Scripps' high-precision measurements of oxygen and carbon dioxide in the air to determine how much heat the oceans have stored during the time span they studied. They measured ocean heat by looking at the combined amount of O2 and CO2 in air, a quantity they call "atmospheric potential oxygen" or APO. The method depends on the fact that oxygen and carbon dioxide are both less soluble in warmer water.

As the ocean warms, these gases tend to be released into the air, which increases APO levels. APO also is influenced by burning fossil fuels and by an ocean process involving the uptake of excess fossil-fuel CO2. By comparing the changes in APO they observed with the changes expected due to fossil-fuel use and uptake, the researchers were able to calculate how much APO emanated from the ocean becoming warmer. That amount coincides the content of the .

Explore further: Ocean's heat cycle shows that atmospheric carbon may be headed elsewhere

More information: Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition, Nature (2018). DOI: 10.1038/s41586-018-0651-8 , https://www.nature.com/articles/s41586-018-0651-8

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30 comments

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Anonym518498
1.6 / 5 (20) Oct 31, 2018
How about the "APBS" levels? Huh? Huh?
TheGhostofOtto1923
1.7 / 5 (24) Oct 31, 2018
Huh. Another major factor that climate scientists knew absolutely nothing about.

And I thought AGW was settled science. Silly me.
aksdad
2.1 / 5 (26) Oct 31, 2018
Resplandy and her co-authors used Scripps' high-precision measurements of oxygen and carbon dioxide in the air to determine how much heat the oceans have stored during the time span they studied.

Oh, so they didn't actually measure the temperature of the ocean. They used a proxy for ocean temperatures that is less accurate than the sparse Argo buoy network and relies on uproven assumptions. Well, as they say, garbage in garbage out.
tblakely1357
1.8 / 5 (21) Nov 01, 2018
"And I thought AGW was settled science. Silly me."

Lol, according to the proponents of AGW it's 'settled' enough for us to send trillions of dollars to unelected, unaccountable international elites to do with as they please while impoverishing ourselves and giving up many if not most of our freedoms.
Thorium Boy
1.9 / 5 (18) Nov 01, 2018
they've gone from 10-350cm rise, and down to 58 for the next hundred years. Despite all the dire predictions, Al Gore still bought a $9m house on the beach in California.
HeloMenelo
4.1 / 5 (26) Nov 01, 2018
look at dumbnuts (antigoracle/askingdaddy) and his goons above looking as silly as ever, these baboons cannot count 1 and 1 together let alone understand the first word about the infinite amount of evidence over decades that Man Made climate change is real, the majority culprit orginizations this goon tries to defend, but only makes him look more dumb by the post. This goon and his socks can't even understand what they see with their own eyes lol..
Parsec
3.6 / 5 (17) Nov 01, 2018
@helomenlo - to be fair the enormous mountain of evidence that has accumulated that AGW is real isn't really infinite. It just seems that way.

The deniers appear to have some speculation about raising dairy cows in greenland in the middle ages as their sole counter argument.

I guess you really can't go wrong betting on the immensity of human stupidity.
TheGhostofOtto1923
2.1 / 5 (18) Nov 01, 2018
@helomenlo - to be fair the enormous mountain of evidence that has accumulated that AGW is real isn't really infinite
Well really, how can we know when just today we learn that

"For each year during the past quarter century, the world's oceans have absorbed an amount of heat energy that is 150 times the energy humans produce as electricity annually..."

-I mean, what other mitigating or exacerbating or extenuating major factors might be out there that we similarly know nothing about?

Seriously.

Be honest - you dont know and you resent having to consider the question.
zz5555
4.2 / 5 (24) Nov 01, 2018
-I mean, what other mitigating or exacerbating or extenuating major factors might be out there that we similarly know nothing about?

Vanishingly small. As this, and many other, study shows, the energy in the climate is increasing. Therefore, it can't be due to internal cycles. It's a boundary value problem - energy in minus energy out. The measured energy from earth's interior is small compared to the measured greenhouse effect and there's no indication of a change that would be required for the current warming. Therefore, it's due to energy coming in and leaving the atmosphere. A lot of data shows it isn't cosmic rays. The energy from the sun has been decreasing since the 70s, so that isn't it. Orbital changes take too long to explain the warming and have been cooling the climate slowly for millennia.
zz5555
4.1 / 5 (23) Nov 01, 2018
That only leaves energy leaving the atmosphere. There's albedo and cloud changes, but again those are too small to account for the warming. That pretty much just leaves changes in greenhouse gases since those are known to control the amount of radiation emitted. And measured greenhouse gas changes do account for the current warming very well. It's also easily shown that humans are responsible for ~100% of the increase in greenhouse gases.

For those hoping some feedback will prevent increased warming. To prevent further warming, you need to increase the radiation to space and that's controlled by Boltzmann and greenhouse gases, so we need to either warm up more or decrease greenhouse gases. The natural removal of excess greenhouse gases takes hundreds to thousands of years, so that won't help us in the near term.
zz5555
4.2 / 5 (24) Nov 01, 2018
Additionally, I'll just say that believing that some heretofore unknown force will save us is as crazy as believing that some mythical sky fairy will save us. There's a reason such plot lines are called deux ex machine in stories.
TheGhostofOtto1923
1.9 / 5 (18) Nov 01, 2018
Vanishingly small
Uh huh. That's what you guys say after every new, major, significant mitigating factor is discovered.

How do I know? Because I've used this very same punchline many times here at physorg.

And of course skeptics have the right to ask 'what's next??' because, as the above article demonstrates, its NOT settled science. And until it IS settled, neither side can legitimately claim that it is...
It's a boundary value problem
...no matter what catchy catchphrases you wish to apply.
rrwillsj
3.9 / 5 (18) Nov 01, 2018
Well otto, using the same logic you apply to denying the cumulative empirical evidence for Global Climate Change...

When you manage to escape your caretakers and steal the keys to their car? As you drive along, if you squint real hard, you might notice the warning signs placed along the road.

Since you do not want to believe the information provided by tax-paid experts? You just disregard those warning signs.

Cause, hey! You are doing fine so far. so why should you care about consequences?

Of course you deny that you are driving like a drunken Mr. Magoo!

Weaving back and forth from one lane to the next. Forcing the other traffic out of your path. Leaving the wreckage and injured strewn behind you without a flicker of conscience on your part.

All they can do is return you to the care facility for the senile, you had escaped from. All you want is that everyone else bear the burden of subsidizing your afluenza existence.
rodkeh
2.1 / 5 (18) Nov 01, 2018
Just more baseless AGW fear mongering!
barakn
4.2 / 5 (21) Nov 01, 2018
How do I know? Because I've used this very same punchline many times here at physorg. -TheGhostofOtto1923

Yes, you've beat the stuffing out of your strawman. Beat him so hard he has to sit down to pee, beat him so hard he's an empty sack, beat him so hard his unborn children are crying. Oh, how his existence taunts you, but still you hold him up to the crowd and cry "Look at how weak this strawman is. Look at what I have done to this strawman."
TheGhostofOtto1923
1.9 / 5 (14) Nov 01, 2018
wow thats so literary barky. Here let me try.

"For each year during the past quarter century, the world's oceans have absorbed an amount of heat energy that is 150 times the energy humans produce as electricity annually..."

-I think mine has more style, more savoir-faire. Certainly says more about the actual state of AGW 'science'.
rodkeh
1.7 / 5 (18) Nov 01, 2018
This is just another example of anti-science here on phys.org!
Old_C_Code
1.7 / 5 (18) Nov 01, 2018
Water is 90% of the greenhouse gases effect. CO2 is not a poison, and doubling it only raises the greenhouse effect worst worst case 2%. No evidence a half degree C increase change the past century has done any harm, and you surely never hear about the good things.
And no evidence a 2 degree change will do any damage either. Unless you listen to political alarmists who are ALWAYS WRONG. Now go bitch about oil, they love it, because you keep the price of oil high with your climate carbon BS. That's reality.
Old_C_Code
1.7 / 5 (18) Nov 01, 2018
the cumulative empirical evidence for Global Climate Change...


We know the climate has ALWAYS changed... genius.
HeloMenelo
4.3 / 5 (17) Nov 02, 2018
This is just another example of anti-science here on phys.org!


But you have proven not to even understand the basics of science, silly monkey... ;)
HeloMenelo
4.1 / 5 (18) Nov 02, 2018
the cumulative empirical evidence for Global Climate Change...


We know the climate has ALWAYS changed... genius.

Same old dumbnuts comment we get here on the science community month after month from antigoracle sockpuppets, pea brains here struggles to realize the meaning of the evidence that the climate changing due to Massive Human Induced Activities has been the main driving factor of these unnatural changes we experience today. Here have another banana, it's the only thing that tickles that lone neuron excited for you ;)
Old_C_Code
1.8 / 5 (16) Nov 02, 2018
Helo: you're an unaccomplished dope. Prove you're not.
Maggnus
4.6 / 5 (9) Nov 02, 2018
Huh. Another major factor that climate scientists knew absolutely nothing about.

And I thought AGW was settled science. Silly me.

Don't be daft. They knew the oceans were absorbing heat, they just underestimated how much. This is still an estimate by the way. Will you reply again to say the same thing when they refine this number further?
Da Schneib
4.8 / 5 (16) Nov 03, 2018
Maybe a lot of people missed this:
As the ocean warms, these gases tend to be released into the air, which increases APO levels.
First evidence of a strong positive feedback.

This is not good news.
TheGhostofOtto1923
1 / 5 (3) Nov 03, 2018
Will you reply again to say the same thing when they refine this number further?
Youre assuming it's not as significant as they say it is? I'm saying its curious that they keep finding significant factors.
Da Schneib
5 / 5 (13) Nov 03, 2018
@Otto, seems pretty significant that everywhere we look the data say the same thing.
Don132
1.4 / 5 (10) Nov 04, 2018
Only in climate science can they take any evidence at all and use it in support of their theory.
The study finds that the oceans absorbed a certain amount of heat. OK. What does that mean? What causes ocean heating?

The authors are jumping to the conclusion that this must be due to CO2. A couple of things should make us doubt this. The first thing is that most atmospheric heating is supposed to occur about 7 miles up in the troposphere, not near the ocean surface; this hotspot hasn't been found (despite Sherwood's butchering of the science) and according to the paper a warming ocean would mean more CO2 outgasing and more feedback and a clearer hotspot; this hasn't happened. The second thing is that it'd take 100 degrees of atmospheric warming to warm the oceans 1/10 degree; it makes a little more sense if we look elsewhere for ocean warming than the atmosphere. A good candidate would be variations in tropical cloud cover.
leetennant
4.8 / 5 (16) Nov 05, 2018
Vanishingly small
Uh huh. That's what you guys say after every new, major, significant mitigating factor is discovered.


You do realise this isn't a mitigating factor, right, but just greater information at the margins? This is like saying "you have a tumour that will kill you in 10 years, oh wait, 9 years" and you respond to that with "There these Doctors go again with this tumour nonsense".

Whether it's 10 years or 9 years, you still have a tumour and you are still going to die - soon. So why would you dismiss the established fact - the tumour - just because the prognosis required more information to bed down? It's certifiably insane. Especially since, in this analogy, your tumour was diagnosed early and your prognosis was excellent - but you refused the surgery because "What do doctors know anyway?"
HeloMenelo
5 / 5 (12) Nov 07, 2018
Helo: you're an unaccomplished dope. Prove you're not.

Lol You have proven us over the years everyday that you are below kindergarden grade, that means you won't understand my scientific qualifications and expertise, besides, conversing with a bafoon is not my style ;)
Da Schneib
5 / 5 (6) Nov 07, 2018
Only in climate science can they take any evidence at all and use it in support of their theory.
Only climate deniers can take any evidence at all and claim it's support for their lies.

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