An Instant Global Ocean Thermometer from Antarctic Ice Cores

Guest post by David Middleton

Why bother with Argo floats and ocean heat content?  Now the average temperature of the oceans can be instantly calculated by the ratio of noble gasses in the atmosphere…

New Study Identifies Thermometer for Global Ocean

Researchers now able to reconstruct past ocean temperatures

Jan 04, 2018

There is a new way to measure the average temperature of the ocean thanks to researchers at Scripps Institution of Oceanography at the University of California San Diego. In an article published in the Jan. 4, 2018, issue of the journal Nature, geoscientist Jeff Severinghaus and colleagues at Scripps Oceanography and institutions in Switzerland and Japan detailed their ground-breaking approach.

Determining changes in the average temperature of the entire world’s ocean has proven to be a nearly impossible task due to the distribution of different water masses. Each layer of water can have drastically different temperatures, so determining the average over the entirety of the ocean’s surface and depths presents a challenge.

Severinghaus and colleagues were able to bypass these obstacles by determining the value indirectly. Instead of measuring water temperature, they determined the ratio of noble gases in the atmosphere, which are in direct relation to the ocean’s temperature.

“This method is a radically new way to measure change in total ocean heat,” said Severinghaus. “It takes advantage of the fact that the atmosphere is well-mixed, so a single measurement anywhere in the world can give you the answer.”

In the study, the scientists measured values of the noble gases argon, krypton, and xenon in air bubbles captured inside ice in Antarctica. As the oceans warm, krypton and xenon are released into the atmosphere in known quantities. The ratio of these gases in the atmosphere therefore allows for the calculation of average global ocean temperature.

Measurements were taken from ice samples collected during the West Antarctic Ice Sheet (WAIS) Divide coring project, of which Severinghaus is a leader. Over the course of six field seasons in Antarctica, a drill removed ice in cylindrical samples 2.7 meters (just under 9 feet) in length. The final sample was taken at a depth of 3,405 meters (over 11,000 feet) in 2011. This record spans nearly 100,000 years and the age of the layers can be determined to within 50 years. Earth’s atmosphere mixes on a scale of weeks to months, so a measurement of these air bubbles gives what is essentially a global average. For this study, scientists focused on samples 8,000 to 22,000 years old, and collected data in increments averaging 250 years in resolution.

New insights into the glaciation cycles that occurred on Earth long before humans began affecting the temperature of the atmosphere and oceans are now possible using the technique of measuring noble gas quantities. The study determined that the average global ocean temperature at the peak of the most recent ice age was 0.9 ºC (33.6 ºF). The modern ocean’s average temperature is 3.5 ºC (38.3 ºF). The incremental measurements between these data points provide an understanding of the global climate never before possible.

“The reason this study is so exciting is that previous methods of reconstructing ocean heat content have very large age uncertainties, [which] smooths out the more subtle features of the record,” said co-author Sarah Shackleton, a graduate student in the Severinghaus lab at Scripps. “Because WAIS Divide is so well dated, this is the first time that we’ve been able to see these subtle features in the record of the deglaciation. This helps us better understand the processes that control changes in ocean heat content.”

This paper is the result of fifteen years of work for Severinghaus, along with graduate students and postdoctoral scholars in his lab. Discussions with another professor at Scripps, atmospheric scientist Ralph Keeling, brought about the idea. Keeling studies the argon levels in the atmosphere to get a similar record of ocean heat going back a few decades. However, air bubbles trapped in ice don’t preserve argon levels accurately. Severinghaus discovered that xenon and krypton are well preserved in ice cores, which provides the temperature information that can then be used by scientists studying many other aspects of the earth’s oceans and atmosphere over hundreds of thousands of years.

Going forward, the ratios of these same noble gases can be determined from atmospheric samples taken anywhere in the world. For example, a measurement from the Ellen Browning Scripps Memorial Pier in La Jolla represents a global average of ocean temperature. Severinghaus hopes to fine tune the procedure.

“Our precision is about 0.2 ºC (0.4 ºF) now, and the warming of the past 50 years is only about 0.1 ºC,” he said, adding that advanced equipment can provide more precise measurements, allowing scientists to use this technique to track the current warming trend in the world’s oceans.

With this study, Severinghaus and colleagues have shown that measurements of noble gases in the atmosphere provide the historical record long sought by the scientific community, and can be further optimized to gain insights into modern ocean temperature changes as well.

This research was supported by the National Science Foundation (grant numbers 05-38630 and 09-44343), and the Swiss National Science Foundation.

Scripps Institution of Oceanography

The paper is behind a paywall.  Here’s the abstract:

Mean global ocean temperatures during the last glacial transition


Little is known about the ocean temperature’s long-term response to climate perturbations owing to limited observations and a lack of robust reconstructions. Although most of the anthropogenic heat added to the climate system has been taken up by the ocean up until now, its role in a century and beyond is uncertain. Here, using noble gases trapped in ice cores, we show that the mean global ocean temperature increased by 2.57 ± 0.24 degrees Celsius over the last glacial transition (20,000 to 10,000 years ago). Our reconstruction provides unprecedented precision and temporal resolution for the integrated global ocean, in contrast to the depth-, region-, organism- and season-specific estimates provided by other methods. We find that the mean global ocean temperature is closely correlated with Antarctic temperature and has no lead or lag with atmospheric CO2, thereby confirming the important role of Southern Hemisphere climate in global climate trends. We also reveal an enigmatic 700-year warming during the early Younger Dryas period (about 12,000 years ago) that surpasses estimates of modern ocean heat uptake.


They assert that this method “has no lead or lag with atmospheric CO2“… which is meaningless because both the new method of estimating temperature and ice-core CO2 are derived from gas bubbles in the ice.  Both would lag behind temperature estimates derived from δ18O ratios in the ice crystals.  They also assert “unprecedented precision and temporal resolution”… But, they were using WAIS Divide ice cores, which turned out to not be of particularly high precision and temporal resolution.  The Law Dome DE08 core has much higher resolution than WAIS Divide.  So, “unprecedented” is unwarranted.

Color me skeptical about the claim that the ratio of argon, krypton, and xenon measured anywhere on the planet or in ice core bubbles yields the average temperature of the world’s oceans to within 0.2 ºC.

Their work does seem to have yielded one useful result:

“Our precision is about 0.2 ºC (0.4 ºF) now, and the warming of the past 50 years is only about 0.1 ºC.”

The warming of the past 50 years is equal to half the margin of error of the new global ocean thermometer.

UPDATE: David and I wrote parallel stories, here’s more detail, including graphs from the paper.



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John Mauer

Very hard to understand “precision” statement with no accuracy statement. Is the paper more explicit?


Accuracy would require that the derived measurement be checked against an actual measurement which is “a nearly impossible task”.

I do admit to being surprised that they didn’t show any warming over the last 50 years.

dan no longer in CA

Yes, it does appear that these scientists don’t know the difference between precision and accuracy.


I think David Middleton’s comment is 97.8937651445% correct.


comment image


So, in sacrificing accuracy for precision all that has been accomplished is to have highly repeatable measurements that may or may not be correct.
Accuracy is hitting the target 3 times, but with some spread. Precision is a tight 3 hole grouping regardless of whether the target is hit or not.
In my field we need both, otherwise bad things happen and people die. We don’t spell close with a “k”.

Gunga Din

Where I work we have a lab scale that can measure to few decimal points of micro grams.
But our MDL (Minimum Detection Level) for one particular test is 2.5 milligrams/liter.
Because our methods can’t be sure of being accurate (+/- 10%) beyond that no matter the precision of our scale.

Gunga Din

Correction. MDL is Method Detection Limit. (Sort of like siting issues for temperature measurements.)
For those who like read: (We went through this.)


Gunga Din – I once sold a scale to a university, and I asked what precision was needed. “It is only for research, so it doesen’t matter” was the reply I got…


I’m sorry but does this mean it’s worse than we thought, or MUCH WORSE….?


If heat be hiding in the oceans, it is well hidden.


Yes, it’s hiding in wells, too. Heat is sneaky.


I wish some heat would hide in my house so my heating bill wasn’t so high.

Bryan A

You could dig one of those Heat Wells beneth your house and heat it radiantly.
And although it does Heat Well,
Digging a Heat Well is a Boring Job.


“You could dig one of those Heat Wells beneth your house and heat it radiantly”

Depending on here you live, you’d have to dig pretty deep to get heat usable without some sort of amplification. I love radiant heat.

Joel Snider

That’s why Global Warming is so dangerous – it’s actually cognizant enough to hide itself from detection.
Probably so it can sneak up on us all at once.

It’s like a giant crocodile, in that way, laying in wait, just out of sight, holding for the moment where we cut the funding that holds it at bay and elect a skeptical president.

Insidious. Diabolical.

Bryan A

tick tick tick tick …


“…and the warming of the past 50 years is only about 0.1 ºC.” Oh, you saw that, too?

I’m glad they put that in writing. Very glad. One-tenth of one degree centigrade is – well, what? Not detectable by nerve endings in my skin? Not distributed evenly?

That’s going to upset the Warmians and Greenbeans and Hot Earth Hippies. Prepare for the howling and angst!!


Okay, David. First of all, understand my view of this.

1 – The CAGWers, Warmians and other climate panic people latch onto ‘mean global temperatures’ as if they were lifelines to a rescue ship, when they aren’t. This 0.1C number will make them splutter and stutter like mad until someone tries to refute it.

2 – A tenth of a degree Fahrenheit or Celsius is only meaningful if it applies to something real. For example, the standard body temperature for humans is 98.6F. There are people whose constant temperature is as much as one degree below that or one degree above it, which may indicate something is medically wrong.
If, for example, my temperature rises by 0.1F, it means nothing other than I may have been in the sun too long, or I’ve been drinking hot tea, or I’m embracing a hot water bottle. If my temperature goes from 98.6F to 99.1F, that’s a full 1/2 degree, which may or may not mean something is medically wrong. It could be simply too much summer sunshine, or it could mean an incipient heat-related problem, such as pending heat stroke, depending on where I’ve been and what I’m doing.
That 98.6F number has direct relevance to not leaving your kids or your pets in a windows-up, locked car on a summer day.
If my own temperature goes from 98.6F to 100.1F, I have a fever, however modest it may be. In a large population group, 100.1F can mean the onset of an epidemic, especially if it rises one more full degree to 101.1F. Now you may have an episode of the Spanish flu pandemic, especially if everyone appears to be exhibiting flu-like symptoms. However, some of the same group may have the same symptoms without as high a temperature, which means they need to be tested for a specific organism.
These are real-world examples in which a mean temperature does count, because it is the standard by which medical people determine your level of illness.

3 – In this instance of world ocean average temperature, the average is meaningless to anyone except the climate change people, because it does not apply to specific locations. Fishermen in Chile depend on the regularity of the El Nino event to predict their potential catch for the season. If the water is too warm, the fish will not come in from the deeper ocean to feed, and those fishermen know it. Since they don’t go out where the larger fishing factory boats go, they can’t take advantage of colder waters. So now, if the sun is in a quiet mode with no sunspot activity to speak of, does that mean there will be an El Nino this time, or will they be able to take in a good haul? And is the rhythm of the El Nino now thrown off?
Specifics do matter in this.

Secondly, unless this average has a long-term effect on the weather, it becomes merely an exercise in arithmetic. I don’t see anything that says ‘huge amount of heat’. If those temperatures range from 9F++ down to 0.05F, the arithmetic refuses to recognize local temperatures which are real-world readings and much more meaningful to those who live in those areas. And taking one reading annually fails to take into account such things as warm blobs of water, which are deep-ocean upwellings from seismic events such as movement on the Juan de Fuca plateline. That will throw off your entire average number system.

The only people who will respond loudly and angrily to that lower-than-expected average number will be the climate hippies and money-seeking climate activists, because it destroys their bone of contention, which is that the world is coming to an end. Now they have nothing to chew on.

I am not saying you’re wrong or that it’s hogwash, because it isn’t.

I’m just pointing out that in the real world in which I live, it has a very low impact on me. This is because it covers too broad an area to mean as much as whether or not the weather forecast is going to be accurate, and how much my utility bills for electricity and gas will be for this month and next. Those charges are determined by the commodities markets, which depend on weather forecasts to set prices. And do I have to keep the taps dripping for another week, or can I shut them off tomorrow?

That average temperature won’t do anything to the weather, because my weather system is generated in Yakutia, in Siberia, sent howling across the northern latitudes, and dropped on my area like a stone. Lake Michigan is 1/3 frozen now. Let’s see if it gets completely frozen, and lasts until June.


DM- how many Hiroshima’s is that? That’s about all I can understand.

Also so they are saying if a large magma chamber moved up under the ocean and heated a vast amount of water, the ratio of noble gases above that area changes (immediately?). So if I’m an argon molecule swimming in the ocean 12,000 ft below the surface of the ocean and it warms up, just how long does it take me to swim to the surface and escape? Or how long does it take for the added heat 12,000 ft down to get an argon molecule near the surface to escape?

I’m sorry but due to the absolute volume of water in the oceans and changing currents, tides, polar air moving over open waters, etc., I’m just a little skeptical that this would “accurately” give us the ocean temp trends to .2C+- over anything less than 50 years or more. I can see out and in gassing over the top few meters of the ocean, but farther down I doubt it will happen fast enough be a measuring tool.


I understand your point, David,

The thing is that in winter, vast amounts of heat in water are lost to evaporation and we get frozen water, which – sunshine or not – doesn’t melt until the season changes. Same thing with snow on my lawn, staying intact despite sunshine, because the house next door casts enough shadow to keep the colder temperature intact (microclimate).

A good, real-time example is the summer of 2011, after the winter in which all the Great Lakes froze over and Lake Superior had ice chunks floating in the water in July. The air temperature was 80F+/-, but the water temperature was still cold enough to keep the ice from completely melting.

If the sun is now in a solar minimum, which seems to be a steady state so far, then the necessary energy required to generate that much heat in the oceans is not forthcoming and probably will not be until the sun returns to more “normal” activity. I’m not sure how much subsurface volcanic activity will do to stir the pot.

I understand your viewpoint completely, enough to say that I hope they have anxiety attacks over those results. Perhaps this will be the “bitter end” of it for them.

rbabcock asks a good question: “if I’m an argon molecule swimming in the ocean 12,000 ft below the surface of the ocean and it warms up, just how long does it take me to swim to the surface and escape?“. According to the paper, the answer is “no time at all”. And maybe that’s the whole point of the paper.

Let me explain.

I see a whole lot of confusion in the comments here. The paper seems to confirm many of the sceptics’ arguments. Yet just about everyone here can smell a rat – this paper wasn’t published to support the sceptics. And let’s face it, the argument about the amount of heat needed to raise ocean temperature has successfully been ignored by the mainstream for donkeys’ years. But no-one can see the rat. We’re being had, but how?

Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.

One of the very few things that the warmist fraternity has struggled with over the years has been the fact that temperature changes lead CO2 changes on all time scales. It has been a very potent sceptic argument, easily understood by most people, and a thorn in their side. OK, they have managed to prevail in spite of it, but getting rid of that fact would be a handy addition to their armoury. And this paper does just that. Every time a sceptic points out that CO2 can’t be causing the temperature rise because the teemperature changed first, they can just point to this paper and use profound scientific sounding words like “Yah boo sucks”. The fact that nothing in their whole case is consistent with anything else in their case is irrelevant. They will have removed the thorn.

As most here have pointed out, this paper is tosh in many differeent ways. But maybe it is the most dangerous paper yet. Do you really expect the general public to understand the difficulty that an argon atom 12,000ft down in the ocean would have, making up its mind whether to leave the ocean or stay? All they would hear is that yet another of the sceptics’ arguments had been demolished. There will probably be another Lew paper out tomorrow saying that 97% is now 99%. And they will believe that too.

PS. Apologies if others have seen the rat already – I haven’t read every comment.

Re: “the climate change people” AKA, “the warmists.”

Just read a column, Jan 4th, over at the American Spectator, “Deconstructing Marxist Critical Theory.”

I’d propose that this applies to ‘the climate change people,” as well:

If progressives were amenable to reason, they would not be progressives.

The rational response to a madman is not to argue with the progressive, but to firmly separate him from any means of doing harm. Progressives must be removed from power, including, at a low level, taking away the public funding that allows them to make careers as full-time street agitators.


@ Rob Bradley, 31 million secs per year.

John Finn

David Middleton January 4, 2018 at 8:32 am

It would take 418,400,000,000,000,000,000,000 (418 gazillion) joules to raise the temperature of 1.37 × 10^21 kg by 0.1 ºC.

David, doesn’t this actually lend support to the AGW crowd’s claims that there is a energy imbalance at TOA. Given that 1 Joule = 1 watt/sec I make it that heat accumulation in the ocean has averaged about 0.74 w/m2 over the past 50 years.

By all means check my figures but I used:
1.58 x 10^9 seconds in 50 years and
area of ocean = 3.6 x 10^14 sq m.

If I’ve got something wrong my excuses is I’ve got a bad dose of flu.

Jim Masterson

January 4, 2018 at 9:29 am

DM- how many Hiroshima’s is that? That’s about all I can understand.

The weapon dropped on Hiroshima was 16 kilotons (of TNT). That is equivalent to about 67 terajoules (67 x 10^12 joules).

DM’s number is 418,400,000,000,000,000,000,000 joules (418.4 zettajoules), and that works out to about 6.2 x 10^9 Hiroshimas (if I did my math correctly).


Matt G

It would take 418,400,000,000,000,000,000,000 (418 gazillion) joules to raise the temperature of 1.37 × 10^21 kg by 0.1 ºC.

so the sun provides 5,700,000,000,000,000,000,000,000 (5700 gazillion) joules per year…..

Over 50 years the sun provides 285,000,000,000,000,000,000,000,000 (285 bazillion) joules.

Therefore the sun only has to increase energy in the ocean by 0.147% over 50 years to have been responsible for all the warming.

Luc Ozade

@ Mike Jonas January 4, 2018 at 11:12 am

But no-one can see the rat. We’re being had, but how?

Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.

I could not agree more – very perceptive.

Another thing, some people on here seem to be putting the noble gases in the ocean, whereas the article states they are in the atmosphere. Am I missing something?

Mike Jonas:

Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.

Yes and no.

There is a lag of about 800 +/- 600 years between ocean surface temperature (where the water vapor of the snow is evaporated) and CO2 in ice cores. δD and δ18O are measured in the ice phase and are a proxy for the temperature at the surface, mainly where water evaporates and where it refreezes to snow. For deep inland ice cores that reflects mainly the temperature changes over Antarctica and part all SH oceans.
CO2 is measured in the gas phase, which always lags the age of the ice phase, due to the time needed to fully close the air bubbles. Even taking that into account, the lag of CO2 vs. temperature is certain, but the exact ice age – gas age lag dating is difficult.

There is no lag between CO2 and the change in temperature of the full oceans. That is what this study says. Both are measured in the gas phase, thus both reflect the increase in temperature from the full oceans, which lags the surface temperature with several hundred years…

Bryan A

and if it takes say 10 gazillion joules to raise the ocean 0.1C, then the ocean has already absorbed 260 gazillion joules since the last glacial max
So around a 4% addition

Peter Sable

It takes a lot of energy (heat) to raise the average temperature of the earth’s oceans 0.1 degree C.

Define “A lot”.

Certainly that much heat, released instantaneously, would burn a city (or more) to a crisp.

Compare to the sun’s output as seen on the Earth integrated over 50 years? Not “a lot” at all.

The ocean is storing heat from one of two possible sources Sun, and the molten core. relative to the heat transferred from those over 50 years, 0.1degC of ocean rise is a meaningless variation.

“a lot” is an emotional statement and has no use in science.



Isn’t atmospheric CO2 levels also based on partial pressures and ocean temperatures. It would be logical that as these gases show increased ocean temperature it would also show CO2 to be at the same time, they are of the same concept.


Looking at the Great Lakes surface temperatures, which seems easier than looking at the whole ocean, temperatures are about the same from year to year. Nothing to be alarmed about there. If global warming was happening I would expect to see something jump out in the temperature data. If there is a high temperature spike, it only lasts a short while. Remember back in 2012 the alarmists were saying no more ice on the Great Lakes, then we had to years of nearly 100% ice coverage? Crickets from the alarmists today.


Yes, right now, Lake Michigan is ahead of 2016 for ice cover, so far. Don’t know about Superior, but if the Coasties are out with icebreakers, they may have more work down the road.


Why hasn’t the UN enlisted the services of Dr Who?

A stroll back to the past in the tardis with a trusty thermometer could clear this up in double-quick time.

michael hart

The atmosphere may be “well mixed” on a scale of weeks to months, but oceans aren’t and ocean currents and overturning seem unlikely to be the same as during an ice age. That must surely affect equilibration rates with the atmosphere.

Kaiser Derden

the atmosphere is well mixed ???? now that we have a satellite that can measure CO2 its obvious that the atmosphere is NOT well mixed … garbage in garbage out … their ignorance is stunning …


It looks clever to me: take advantage of noble gas equilibrium temperature. Since they are so nonreactive, they are a decent candidate as a proxy of global temperature of the ocean in which they dissolve.
However, to turn the theory into a practical tool needs skills, very precise measures of noble gas concentrations, serious exploration of the conditions (just for example: atmosphere may be “well mixed” at the month time scale, but the ocean takes years (centuries? millennia?) to mix.), etc.

Any prospect of it being possible is enough to justify, right now, the keeping of a record of noble gas concentration with the highest possible accuracy, the way Mauna Loa Observatory does with CO2.

My guess is, is won’t be done anytime soon. This would show the ocean is a HUGE heat reservoir with very minute temperature change, and efficiently damping “climate change”, Nothing to scare people with.

Crispin in Waterloo

Just because the xenon is well mixed and reflects temperatures on an instantaneous basis does not mean CO2 reacts similarly. It should be trivial to compare xenon and CO2. CO2 is strongly involved in the carbon cycle and the noble gases are not.

It seems reasonably that CO2 can follow temps with an eight hundred year delay. There are a lot of papers reporting this as a fact. Now, let’s see the gases plotted at the same time, using xenon as the real time guide.


Of course CO2 doesn’t react the same, that’s the whole point. Noble gas cycle are much simpler than O2, CO2, or N2 cycle, basically reduced to cycling between ocean and atmosphere.

alastair Gray

Are we talking about a bulk temperature of the ocean, or the temperature of the top milimetre? .Presumably rare gases get exchanged between ocean and atmosphere only at the boundary layer between water and air, and it will be a 2 way process. If that is the case then the equilibrium gas ratios may have a temperature dependence. To be useful as a proxy We would need a heck of a lot of reliable sensitivity validation in terms of Delta(gas composition ratio n) /degree C and
I am not sure where this would come from. On the other hand if we seek a correlation to bulk temperature of entire ocean the response gas ratio mixing time of the entire ocean to a surfacegas ratio change would I think be millenia. So I will assume until proven otherwise that our 0.1 deg C change refers to the sea surface only. Subject to thyese caveats it seems like a worthwhile piece of research. How about extending in time e.g.Gas inclusions in Resin blobs (Thank you Michael Crighton and Jurassic park) Any other source of dateable air bubbles free of contamination?

Congratulations to Jeff! This seems a great idea and gives us a new proxy to play with.

That “We also reveal an enigmatic 700-year warming during the early Younger Dryas period (about 12,000 years ago) that surpasses estimates of modern ocean heat uptake.” could make the abstract shows a sophistication beyond the CO2 control knob. Jeff has done prior work showing extremely rapid warming, much faster than today; before any possibility of human influence.

Not entirely convinced that this claim was subjected to any informed review before they went ahead and clicked “print”.

The world in a single grain of sand?


… or the entire universe from one small piece of fairy cake, as in the Total Perspective Vortex!

I was going to ask if some Douglas Adams reincarnation or ouija thing was going on… the improbability function of the proposed single measurement obviously collapses into the correct answer = voila!

15 years of work for the researcher… I would say I’m very skeptical, but I’d hate to rain on his parade.

Search teams are being assembled to head off out and conduct a search for Scripps credibility which seems to have been heading south.

Mark - Helsinki

“Color me skeptical about the claim that the ratio of argon, krypton, and xenon measured anywhere on the planet or in ice core bubbles yields the average temperature of the world’s oceans to within 0.2 ºC.”


Are these guys serious?! Of course there is no way to tell they are right because truth be told no one has a clue what the average temperature of all ocean water on earth is, lol, maybe when they get millions of buoys around the oceans and at various depths from the bottom to the top of the oceans.. then maybe I will listen.

More junk science.

Michael Jankowski

One could seemingly set-up lab experiments to verify the results. But the temperature-dependent chemistry seems well-established in those already.

Ben of Houston

The basic chemistry, yes, but that’s local average temperature only. Not planetary average. The basic science is good, but the extrapolations are ridiculous.

The amount of energy required to raise the ‘average’ ocean temperature by 0.001ºC cannot be calculated using present-day thermometers. For a start, there are no Argo floats in the Arctic ocean and records only exist for the top half of the remaining oceans.

Crispin in Waterloo

Bobburban, point taken, but it would be more correct to say, calculations aside, that a change in the average ocean temperature of 0.001 C is not measurable with modern equipment.

There are to reasons: the RTD’s used do not have that precision and the uncertainty about any calculated value is far greater than 0.001. More like 0.5C. The rest is noise.

> …said Severinghaus. “It takes advantage of the fact that the atmosphere is well-mixed, so a single measurement anywhere in the world can give you the answer.”

Fact? Especially funny as the East Coast huddles While we here in SoCal are wearing shorts. The Noble gases are not even remotely well mixed. Ask anyone with a Radon detector in their basement.

Michael Jankowski

He’s referring to gas concentrations in the atmosphere, not temperature.

What do contained houses and basements have to do with atmospheric mixing?

Severinghaus is demonstrably wrong in his assertion that noble gases are well-mixed in the atmosphere.

Basement Radon detectors are not even common. Radon as a noble gas should be according to Severinghaus well-mixed. It is not.

Ian W

There are plumes of Radon from the various granite cities for example Aberdeen Scotland. So a measure of radon in Antarctica is unlikely to show the level of Radon on the East coast of Scotland or even the Northern Hemisphere. Well mixed only applies if there are no point sources of a gas.

This paper seems to be based on very shaky assumptions, the major one being that it is possible to know the temperature of the entire world ocean with an accuracy of a tenth of a degree. It is probably impossible to know the temperature of a swimming pool with an accuracy of tenth of a degree.

Crispin in Waterloo

They were careful to identify which noble gases are well mixed. Confirmation is easily checked by referring to measurements made at Earth Monitoring stations such as in the Arctic and Cape Point.

Rob Dawg,

Well mixed doesn’t mean that at every moment anywhere on earth exactly the same air composition is measured. Where huge sources (and/or sinks in the case of CO2) are at work, you will find much higher (or lower) ratio’s. Measure radon or CO2 in a floorless dome over a sandy soil and you measure a lot of both, much higher than in ambient air. Measure the same at the top of Mauna Loa or at the South Pole and you will find the same ratio’s, within the seasonal variability for CO2, which is mainly in the NH.

As the resolution of the WAIS divide ice core still is several hundred years, the fast mixing of any disturbance by local sources is completely averaged out and may reflect the solubility – thus temperature – of different gases in the oceans…

Jeff Id

The precision of a 50 year trend is much greater than the precision of a single measurement.

Not that I believe either without reading the paper.

“Determining changes in the average temperature of the entire world’s ocean has proven to be a nearly impossible task due to the distribution of different water masses.”
No WAY!?

From “Bereiter and colleagues’ work provides an unambiguous record of the average temperature of the entire ocean, from the surface to the greatest depths. However, it does not directly quantify surface temperatures — either global average surface temperature or sea surface temperatures, both of which are useful for understanding and quantifying glacial–interglacial temperature differences and processes. The authors do provide a rough estimate of average surface temperatures from their data, by using a cohort of models to estimate the ratio between sea surface temperature and mean ocean temperature. But this constrains surface temperatures only weakly, highlighting the need for more work in this area.

So, simultaneously, the sea surface temperature has risen by 0.1 but the study does not quantify surface temperature?

Moreover, there is relatively little time delay between changes in ocean temperature and corresponding changes in the noble-gas signal, compared with many other proxies — the ‘lag-time’ of the noble-gas tracer is less than 100 years.

Warming of 0.1°C ±0.2°C – oh.

Steve Zell

It’s possible that the ratio of one noble gas to another might be a proxy for temperature of the surface of water where these molecules were emitted, but as “rbabcock” rightly pointed out, these noble-gas measurements would have little relation to water temperatures more than 100 meters below the surface. These researchers can’t use the noble-gas concentration ratio to estimate the temperature of the entire ocean, but only the part within a few meters of the surface.

Another problem is that the researchers only measured noble-gas concentration in ice cores in Antarctica. These noble-gas molecules must have been dissolved in a raindrop or snowflake that landed on Antarctica in the past, which probably fell from a cloud located south of 60 degrees south latitude. It would be highly unlikely, if not impossible, for a raindrop that formed over the tropics or the Northern Hemisphere to travel horizontally for thousands of miles to Antarctica while falling only about one mile from a cloud.

This means that the noble-gas ratios in Antarctic ice may be a proxy for ocean surface temperatures within several miles of the coast of Antarctica, but by no means for the surface of the oceans of the entire earth. It is entirely possible that sea surface temperatures were rising in the tropics and/or Northern Hemisphere (or temperate areas of the Southern Hemisphere) while they were falling near Antarctica, and vice versa.

Steve Zell,

My objection too: the fastest reaction is from the surface layer (average 200 m), the rest would follow with much longer delays, as good as is the case for CO2 from the deeper oceans: a response time of about 800 years…

What they measure is not the noble gases which were dissolved in rain, they measure the noble gases in the enclosed air in the ice. Snow is about 80% air and 20% ice. When compacting, the air is fully enclosed at a depth below 70 meter. In between the air still can exchange molecules and atoms with the atmosphere at the surface, less and less with depth as the pores get smaller and smaller.

The Reverend Badger

Even if you spent a trillion dollars a year you are not going to get an accurate measure of the average temperature of the entire volume of all the oceans in the world to better than about +/- 2K.


I have been religiously monitoring argon, xenon and krypton gases ever since kindergarten.
Let me tell you! It is very exciting!


That’s very noble of you….


What do the microbes in the ice cores eat?

— Cinaed



Depends of the ice temperature and the availability of inclusions. At Vostok with ice average -40ºC, they just survive, without any growth, by repairing their DNA. For that reason they even use CO2 and oxydise traces of ammonia (NH4) to N2O as energy source. If all N2O was from this source, the difference in CO2 level would be less than 0.1 ppmv…
See further item K. in:

Pamela Gray

But does this not mean how much heat has been coughed up and out of the oceans? Since ice cores measure change in atmospheric gases, is this reflecting heat discharge or recharge?

Pamela Gray

Also, does this mean the oceans were overall calmer thus layered up with heat on the top, or mixed with heat not layered up?

Pamela Gray

Also, does this mean the oceans were overall calmer thus layered up with heat on the top, or mixed with heat not layered up?

Peter Sable

So how would one falsify such a method for estimating global sea temperature?

You could falsify the precision by taking hundreds of measurements across the planet at the same time over a period of several years and seeing if they disagree.

There’s no accurate measurement to compare it to. So you can’t falsify the accuracy.

It’s not even wrong.


Luc Ozade

Kudos to Mike Jonas, above, for his pinpointing of the most worrying aspect of this paper:
blockquote>Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.
I did spot this on reading the paper and am surprised that nobody else has replied to Mike’s comment.

Luc Ozade

That didn’t come out right – my keys are a bit sticky:

Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.

Luc Ozade

I do so wish people wouldn’t move on so quickly to the next article of the day. It’s one of my few beefs with WUWT about having so many to try and keep up with.


Not sure about that. If there is no lag between ocean temperatures and atmosphere composition it is obvious that ocean temperature changes are driving atmospheric changes and not the other way around. We have done the experiment and it takes a lot longer to change the temperature of the ocean than to change the composition of the atmosphere. That sort of kills the argument that CO₂ has been the climate driver of the past.

Precisely what we are seeing now is that ocean temperatures present a very important lag when we change atmospheric composition. The ocean has warmed by only 0.1°C, so that lag is bigger than 50 years.

Which brings us to the question of the temporal resolution. They analyze 10,000s of years. What does it mean no lag? ±50 years? ±200 years?


According to the ice cores the lag between surface temperatures and CO2 is 800 +/- 600 years.
As this research looked at total ocean temperatures, the lag still is the same, as the deep ocean turnover is about 800 years.
The noble gases were measured in the gas phase, as good as where CO2 is measured. Thus most of the historical CO2 increase/decrease was induced by the deep oceans…


Great science – maybe they can get a noble price….?

Geoff Sherrington

In the lab you measure the partitioning of inert gases between gas and liquid phases using apparatus that keeps the liquid stirred so that one source of uncertainty is minimised..
You can derive reproducible parameters that way.
When you get to oceans, they are not uniformly stirred. If you do not do your partitioning measurements for long enough time, you will not reach an equilibrated experiment so you can’t compare with lab constants. At best, you can make some assumptions about ocean mixing and get some data, but you will never know if it is correct. The assumptions you make about ocean mixing might require a time longer than yours. Geoff.


David wrote: Color me skeptical about the claim that the ratio of argon, krypton, and xenon measured anywhere on the planet or in ice core bubbles yields the average temperature of the world’s oceans to within 0.2 ºC.

Let’s be skeptical for a moment. Do the solubility of a gas vary with temperature? Check. In a simple enclosed system of water and a single gas, can measuring the amount of the gas in the air tell us the temperature of the water? Check. To within 0.2 degC? Possibly. If we make the system more complex and use a mixture of gases, can it still work? Check. Will this gas stay inside air bubble in ice caps? Maybe. CO2 is much larger. Maybe argon diffuses to fast.

The problem is that it takes about 1,000 years for the ocean to mix. Any air bubble being trapped today reflects the AVERAGE temperature of the ocean over the last thousand years. One may be able to measure krypton and xenon accurately enough to report temperature within 0.2 degC, but the time point associated with that temperature is broad and uncertain. This proxy can’t tell us anything useful about anthropogenic climate change because it responds too slowly.


There is only a problem with the smallest molecules/atoms at the time of bubble closing. krypton and xenon are large enough, but argon does show some diffusion in firn just before closing. See table 1 in:

As that work is also from Severinghaus (and Battle), I suppose that they have taken that into account

Ian W

Frank, the problem is that you cannot assert that you know the ‘average temperature of the world oceans’ to within a tenth of a degree. Indeed as any metrologist would tell you you probably cannot measure the temperature of a swimming pool with an accuracy of 0.1C, Just because the precision of the maths being used is tenths of a degree does not mean that the results are accurate within a tenth of a degree.

I am amazed that this paper passed peer review.

Well I think the answer lies in this sentence: “ We find that the mean global ocean temperature … has no lead or lag with atmospheric CO2“.

As Ferdinand and Frank point out one would think that the time for atmosphere/ocean equilibrium would be directly related to the 600-800-year average ocean turnover rate for the water to interface with the surface. This would cause exactly the lag and buffered response as CO2. In fact, if the ice core plots do not match for each type of gas that would be an indication of error or some unknown dynamics. This brings up a question if anyone knows if the CO2 levels in ice cores are normalized the fact that many gasses are fluctating in concentration with ocean temp, not just CO2. Thus the increase in ppm concentration of one gas is not necessarily an absolute increase (partial pressure). It could be that the other gases got diminished by greater absorption in the ocean.

Ron Graf,

The only corrections done are for gravitational enhancement: at a certain depth, there is no exchange anymore with the air at the surface due to wind and pressure changes.
In stagnant air, the heavier molecules and isotopes tend to sink to the bottom of the firn down to just before closing of the pores.
That is compensated for by measuring the 15N/14N ratio change, compared to the current air isotopic composition. The compensation anyway is less than 1% for CO2.

For other changes: all ratio’s are measured in dry air, thus water vapor is excluded. Argon is the largest item present besides nitrogen and oxygen at near 1%. Any changes in ocean temperature will affect the Ar/N2 ratio and the CO2/N2 ratio independent of each other, as per Henry’s law each gas will have its own equilibrium partial pressure independent of all others – even at full vacuum.

Thanks Ferdinand. Yes, Henry’s Law establishes gases that a gas’s partial pressure is based on its concentration inside the medium it’s dissolved in (at equilibrium). But the ppm concentration in that gases partial pressure relative to all the gases combined partial pressures. As global temperature mean changes all the gases increase or decrease in concentration in the ocean while changing their ppm component in air only because their solubility properties vary. If we can accurately measure krypton and xenon, knowing these gases’s solubility are unaffected by plankton concentrations or volcanic activity, they would show a clear baseline for the GMST and dissolved gas lag. If CO2 varies from that baseline one would suspect variation is indicating volcanoes or plankton or surface greening.

Max Hugoson

The first time I looked at this, I didn’t read through it thoroughly enough. The second time I found that Middleton did say: “Color me skeptical about the claim that the ratio of argon, krypton, and xenon measured anywhere on the planet or in ice core bubbles yields the average temperature of the world’s oceans to within 0.2 ºC.

Their work does seem to have yielded one useful result:

“Our precision is about 0.2 ºC (0.4 ºF) now, and the warming of the past 50 years is only about 0.1 ºC.”

The warming of the past 50 years is equal to half the margin of error of the new global ocean thermometer.”

It would seem that the standard definition of “precision” would indicate that if the “temperature rise” over the last 50 years was 0.1 C, you CANNOT SAY THAT WITH CERTAINTY, as it is less than your “measurements statistical fluctuation”. I.e., if you had an instrument measuring 0.000000 (forever)…and
it was putting out 0.0000, 0.005, 0.2000, -0.20000 any tabulation of any amount of the data points, which averaged to any value more or less than 0.2 or -0.2 (say a set of 10,000 data points, averaged to 0.05233423 …it would still mean 0.0 !!! I.e., the averaged number would have NO SIGNIFICANCE. But it’s nice to know, that their result has shown with 100% confidence that the change in “ocean temperature” over 50 years is LESS than 0.2 C upward and less than 0.2 C downward. (Another semantic brain twister.)