Sensitive side (from the NASA Global Climate Change Website)
By Rosemary Sullivant,
NASA Jet Propulsion Laboratory
A little extra carbon dioxide in the air may, unfortunately, go further towards warming Earth than previously thought. A team of British and U.S. researchers have uncovered evidence [1] that Earth’s climate may be up to 50 percent more sensitive to long-term increases in atmospheric carbon dioxide than current climate models predict. The reason for the underestimation, they say, may be due to long-term changes in ice sheets and vegetation that are not well represented in today’s global climate models.Just how much will global temperature rise in response to increases in atmospheric carbon dioxide? This is one of the key questions that climate scientists need to answer. According to the climate models used in the most recent report from the Intergovernmental Panel on Climate Change (IPCC), doubling the amount of carbon dioxide in the atmosphere from pre-industrial levels is expected to warm Earth by about 3 degrees Celsius (5 degrees Fahrenheit), once the atmosphere and oceans spend a few years or decades adjusting and reaching a balance.
But according to a recent study by a team of researchers that includes Gavin Schmidt of NASA’s Goddard Institute for Space Studies, Earth’s climate is also influenced by other, much slower processes. These include changes in ice sheets, vegetation and aerosols, for example, that take place over hundreds and thousands of years.
Because of their complexity and long timescales, these processes are almost impossible to integrate into today’s climate computer models. As a result, it has been difficult to know just what their effect on Earth’s climate sensitivity would be.
To learn more about this sensitivity, Schmidt and his co-authors looked back 3 million years into Earth’s past. They used a computer model that describes the oceans and atmosphere to predict, retroactively, the climate of the mid-Pliocene — a period when both global temperatures and atmospheric carbon dioxide concentrations were higher than today. The model substantially underestimated just how high temperatures would go. When the researchers adapted the model to include the effects of long-term climate changes in vegetation and ice sheets, they were able to get a much closer representation of the warming in the Pliocene era.
The team found that it took much lower concentrations of atmospheric carbon dioxide to recreate the Pliocene’s warm climate than current models — which consider only the relatively fast-adjusting components of the climate — predict. Pliocene carbon dioxide levels are estimated to have been around 400 parts per million by volume (ppmv), while according to current simulations it would take 500 to 600 ppmv of carbon dioxide to bring about the warm temperatures of the Pliocene. As a result, the researchers estimate that Earth’s response to elevated concentrations of atmospheric carbon dioxide is 30 to 50 percent greater than previously calculated. In other words, the climate is more sensitive to carbon dioxide than we thought.
This higher sensitivity of the climate should be taken into account, the team concludes, when targets are set for limiting greenhouse gas emissions. The results of the study appear in Nature Geoscience.
Research paper: [1] Daniel J. Lunt et al., “Earth System Sensitivity Inferred from Pliocene Modelling and Data,” Nature Geoscience, Vol. 3, No. 1 (2010).
PDF Here
I’m amazed. How do they have the guts to publish stuff like this?
The models are wrong for the Pliocene (500-600 ppm needed vs the 400 that occurred) – admittedly deficient in a number of aspects (changes in ice sheets, vegetation and aerosols) – and the conclusion is: CO2 is even more sensitive?
OMG.
An easy question to ask is – wouldn’t we have seen this even GREATER warming revealed in the past 10 years or so – say, since 1998 ?
The answer seems to be: my model is right, the earth is wrong !
This is embarrassing !
geronimo says:
May 5, 2010 at 10:40 pm
“Is this what happened to cause the MWP? And if so what reversed it?”
Apparently we were saved from a runaway Medieval Warm Period by the black plagues. The decreased farming allowed trees to grow and suck up the CO2. If that small number of people had that great effect back then, what about now? Wow! They do throw in the Native Americans and accuse them of adding to the catastrophic farming; then, of course, Europeans introduced diseases and killed them off, also.
Gavin is trying to find sensitivity everywhere because work such as Miskolczi and Zagoni, based on real world confirmation of their work, is indicating that CO2 and water vapor interact to have a constant effect and the substitution of an inferior heat-trapping gas for water vapor may even cool the climate a tiny bit.
Gavin is really trying to give mouth-to-mouth to a dead horse.
“Because of their complexity and long timescales, these processes are almost impossible to integrate into today’s climate computer models.”
“When the researchers adapted the model to include the effects of long-term climate changes in vegetation and ice sheets,”
Is this not a contradiction?
Perhaps Gavin should always include a theme song with his work; how about “The Impossible Dream”.
This is all you need to know about this paper…
“Here we use a coupled atmosphere-ocean general circulation model to simulate the climate of the mid-Pliocene warm period (about three million years ago), and analyse the forcings and feedbacks that contributed to the relatively warm temperatures.”
where “coupled atmosphere-ocean general circulation model” is probably the notorious Model E…
There was an ice age during the Ordovician with CO2 levels an order of magnitude higher than today. Why did Gavin stop at 3 million years?
GISTEMP is in the same building with Gavin. If he had lunch with them once in a while, he would know that temperatures have only increased by 0.6C in the last 120 years.
Those of you who regularly visit this Website know that I frequently make comments built around my birdfeeder and the sometimes mythical birds that visit it. Like Fat Albert, the gluttonous dove, or Catlin’s warbler who can’t sing except a sad song for North Korea. [Don’t cry for me North Korea]. As you might imagine I am always on the lookout for a new bird for my birdfeeder. I have a new bird. It’s called the Schmidtbird.
Among the various bird attractions we have in our backyard are many hugh holly bushes. We had a bumper crop of holly berrys this year. What happened was astounding. The robins came for the berrys. I am not talking about twenty, or fifty, or even a hundred. I’m talking about a stunning array of multihundreds. Our backyard was alive with the sound of birds. Not one single Schmidtbird, however. None, nada, zip. Maybe I was offering the wrong kind of berry.
I’m sure everyone reading this knows what a dingleberry is. Three adults live in my house. Maybe if we all collect dingleberrys and I put them on the deck rail the Schmidtbird will come feed. I promise to take a picture and send it to Anthony. I’ll bet he posts it faster then a robin eats a holly berry.
> This higher sensitivity of the climate should be taken into account, the team concludes, when targets are set for limiting greenhouse gas emissions.
It would follow that the current climate models also need adjustment to reflect the higher sensitivity. That was we won’t have to wait as long to see them heading off in the wrong direction.
Ah, Gavin, what was that word we were looking for ? was it THIMK ? (as what goes on in your head ) or was it modol as in Sharon Stone. sarc off.
What amazing baloney. What a huge waste of taxpayer money. Amazing how they avoid periods of higher CO2 and lower temperatures than at present.
Combine with the first comment about the arctic declining and you have an epic amount of silly.
Yeh yeh, we get it Gavin. Here is the gist of study after study and it won’t cost tax payers a dime for the next one. In fact throw out that energy eating super computer and just do mind experiments. Write it up as follows:
Introduction
…the Earth is highly sensitive…
Literature Review
…catastrophic…
Problem
…much worse…
Methods
…the Earth is highly sensitive…
Results
…catastrophic…
Conclusion
…much worse…
Neil Crafter says: May 6, 2010 at 12:02 am
Assuming this is a genuine question and not a wind up …
Yes, it is a way of depicting the molecular bonds. The carbon dioxide molecule is linear with a carbon atom in the middle, flanked by two oxygen atoms (as shown). The molecular bonds consist of electrons shared between the oxygen atoms and the carbon atom. Notionally, each oxygen atom shares 2 electrons with the carbon while the carbon atom contributes 4 electrons. The so-called “double bond” is particularly stable. The rod, of course, is merely a way of picturing the arrangement.
“The team found that it took much lower concentrations of atmospheric carbon dioxide to recreate the Pliocene’s warm climate than current models — which consider only the relatively fast-adjusting components of the climate — predict.”
Interesting, the all to obvious conclusion should have been that something else (NOT CO2) is driving the climate because lower concentrations of CO2 in the past have produced much warmer climates. We all knew this.
Instead, the paper looks like a revisionist attempt to explain paleoclimates from the blinkered view that CO2 has to somehow be (even when data suggests the opposite) the main driver of climate.
Poppycock
This is part of the hideous and most silly prophet. I just didn´t know until a few minutes ago that AL BABY had taken the Nobel Peace Prize away from the hands of a woman, Irena Sendler, who saved 2,500 jewish children from being killed, during the II WW.
Could anyone have accepted the prize knowing this?. This abominable act says it all about how menacing is this guy for the world.
JER0ME at 1:48 am:
THAT was great! I have done that many times and every study/report should be edited(?) analyzed(?) that way! AND there should be a law in grant funding that says, “A $10,000 reimbursement to the Gov. funding agency must be made for every ‘more than’, ‘may be’, ‘expected to’, ‘may’, ‘models predict’, ‘not well represented’, ‘is expected’, ‘almost impossible to’, ‘difficult to know’, etc….. in your final report.”
Yeah, like that’ll ever happen..
It’s NOT SCIENCE if you’re guessing! And computer models (in most of these cases) are nothing more than higher speed guessing tools!
To our UK friends, thanks for funding this research (though I bet the US kicked in some “stimulus” money to fund Gavin and his Model E runs)…
http://www.sciencedaily.com/releases/2009/12/091206162955.htm
“This research was funded by the Research Council UK and the British Antarctic Survey.”
Meanwhile…Europe and the USA go further into debt…
A computer model to predict the past.
All computer algorithms only give the answer the programmer chose
This is just a cherrypicked short period of time where they can exaggerate the CO2 sensitivity value. There are a few cherrypick opportunities in the paleo record where you can numbers like this but for the vast majority of the rest of the record, it does not work and one can even get negative sensitivites.
3.5 million years ago, temperatures were about 2C higher and CO2 levels may have been close to 400 ppm (according to a few new estimates).
But this looks to be the highest CO2 levels in the last 24 million years. For the rest of the past 24 million years, CO2 levels were between 200 ppm and 350 ppm. It was as much as 4C warmer at these other periods when CO2 was actually lower.
Gavin and his partner Daniel Lunt, should run their climate models for the entire record rather than just cherrypick one short period when the numbers can be exaggerated.
This is from Mark Pagani in Nature last year. (CO2 and temperature over the last 50 million years – note the temperature chart is upside down really).
http://www.nature.com/nature/journal/v460/n7251/fig_tab/nature08133_F1.html#figure-title
Over half a century ago, a notorious propagandist once said “If you tell a lie big enough and keep repeating it, people will eventually come to believe it.”
It’s interesting to go back to the pre-global-warming-hysteria science and look at what scientists thought then. The consensus seemed to be that the Pliocene was warmer than the present mainly because there was a gap between North and South America that allowed circulation between the Atlantic and the Pacific. When that gap closed, it forced ocean circulation to the poles and within a million years or so you had cyclical glaciers/interglacials. No carbon dioxide surplus required. In other words it was much different planet back then. I see no reason to think the consensus was wrong back then.
I think Gavin and company are smart enough in their own way, but they have blind spots. They’re coming into this from sciences that don’t really deep-down understand how different the world of the past was. They come in and thrash around with stuff like this, and the people in sciences like geology and paleontology for the most part bite their tongues and mutter about people who think they’re experts on everything.
They also don’t deep-down grasp how much influence the presence or absence of certain key animals can influence climate. Take elephants for example. When poachers shoot out elephants in an area, in a lot of cases the area turns from savanna to forest. What does that do to the albedo of the area? Depends on the underlying soil. Now, in the Pliocene elephants or their equivalents (Mammoths and Mastodons) were on every continent except Australia and South America. They made it to South America either shortly before or shortly after the land-bridge formed. They went extinct over much of the world at the end of the last ice age (along with most of the other large mammals outside of Africa and tropical Asia. How did that change the way the ecology of most of the world’s land mass worked? Considerably. What impact did that have on the albedo of the earth? On wind speeds? I don’t know. I don’t think Gavin and company do either.
Speaking of unexpected climate impacts of large mammals, apparently over-whaling has an interesting impact: whale feces is rich in iron and apparently plays a major role in allowing plankton to survive in iron-poor parts of the ocean, which in turn increases the ocean’s ability to absorb CO2. Over-exploiting whales = less CO2 absorbed in the ocean. I’m guessing that we’ll find a lot of other subtle climate impacts of fewer whales as we start to really understand climate. I haven’t done the math yet, and I’ve never seen it documented, but I think fewer whales probably means at least some reduction in clouds over the oceans. A major impact? Don’t know.
Speaking of iron and plankton, apparently dust from large volcanoes is also a source of iron for iron-deficient parts of the ocean. It would be interesting to look for reductions in CO2 concentrations in the atmosphere after the big strato-volcanoes like Tambora or to a lesser extent Krakatoa or even Pinatubo. Any impact from Pinatubo would probably be masked by the stuff from fossil fuels, but the earlier volcanoes might have had a subtle downward impact on CO2 and thus (if we buy AGW) on temperatures just when thermometers were getting widespread enough for us to establish a base period.
These poor guys don’t seem to realise that the more they prosletyze this sort of nonsense, the more they are tightening the noose around their silly goose like necks. At risk of mixing metaphors – they’ve not only gone out on a limb, but have now begun sawing the branch from the trunk. Highly amusing.
They used a computer model that describes the oceans and atmosphere to predict, retroactively, the climate of the mid-Pliocene
To imagine things is human, to really go off the deep end faster than previously imagined is to use a computer model.
It’s ok to imagine, it’s in our nature to want to know.
But that is really all Gavin & C0. are doing here: Computer-aided imagination.
Fine. Just make sure that, before getting on the horn to stampede civilization over a cliff, you find a way to gather the geologic evidence that the rest of us can examine too.
If Gavin & C0.’s imagination is not tested with evidence, it remains in thier heads.
Pleasant dreams.
Gavin, as a subjective researcher, is unable to accept that global temperature differences are the driving forces that control the global concentrations of CO2 and that CO2 is not a driving force controlling temperature. Yes, there is a correlation and sea ice and land cover are significant factors, but a cause and effect relationship does not involve CO2 in the earth’s heat balance. http://www.kidswincom.net/CO2OLR.pdf.
A second major problem is trying to estimate response times using proxy data averages with time resolutions of thousands of years. http://www.kidswincom.net/climate.pdf.
“Because of their complexity and long timescales, these processes are almost impossible to integrate into today’s climate computer models. As a result, it has been difficult to know just what their effect on Earth’s climate sensitivity would be.”
So they are saying it can’t be modeled but it’s there none the less? To me this does nothing but add uncertainty. In fact, what they are saying is that they tried to test their models against Pliocene conditions and because they didn’t work they just spun it to the favor of their hypothesis rather than reporting it as a failure of their models. The headline on this piece by Sullivant should read “CLIMATE MODELS FAIL TEST.”
When I saw the use of models as a source of facts instead of observation, I shut it down. Compputer models of birds evolution give males and females the same feathers. How do modelers deal with discrepancies and changes?
This may be why Mann is going to court. He sat in an armchair and paid a student to write a model instead of doing field work and travel.
The love affair with unverified climate models continues.