Global warming: Our best guess is likely wrong

Jul 14, 2009
A new study suggests scientists' best predictions about global warming might be incorrect. Credit: Rice University/Photos.com

No one knows exactly how much Earth's climate will warm due to carbon emissions, but a new study this week suggests scientists' best predictions about global warming might be incorrect.

The study, which appears in , found that explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth's ancient past. The study, which was published online today, contains an analysis of published records from a period of rapid climatic warming about 55 million years ago known as the Palaeocene-Eocene thermal maximum, or PETM.

"In a nutshell, theoretical models cannot explain what we observe in the geological record," said oceanographer Gerald Dickens, a co-author of the study and professor of Earth science at Rice University. "There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models."

During the PETM, for reasons that are still unknown, the amount of carbon in Earth's atmosphere rose rapidly. For this reason, the PETM, which has been identified in hundreds of sediment core samples worldwide, is probably the best ancient climate analogue for present-day Earth.

In addition to rapidly rising levels of , global surface temperatures rose dramatically during the PETM. Average temperatures worldwide rose by about 7 degrees Celsius -- about 13 degrees Fahrenheit -- in the relatively short geological span of about 10,000 years.

Many of the findings come from studies of core samples drilled from the deep seafloor over the past two decades. When oceanographers study these samples, they can see changes in the during the PETM.

"You go along a core and everything's the same, the same, the same, and then suddenly you pass this time line and the carbon chemistry is completely different," Dickens said. "This has been documented time and again at sites all over the world."

Based on findings related to oceanic acidity levels during the PETM and on calculations about the cycling of carbon among the oceans, air, plants and soil, Dickens and co-authors Richard Zeebe of the University of Hawaii and James Zachos of the University of California-Santa Cruz determined that the level of carbon dioxide in the atmosphere increased by about 70 percent during the PETM.

That's significant because it does not represent a doubling of atmospheric carbon dioxide. Since the start of the industrial revolution, carbon dioxide levels are believed to have risen by about one-third, largely due to the burning of fossil fuels. If present rates of fossil-fuel consumption continue, the doubling of carbon dioxide from fossil fuels will occur sometime within the next century or two.

Doubling of atmospheric carbon dioxide is an oft-talked-about threshold, and today's climate models include accepted values for the climate's sensitivity to doubling. Using these accepted values and the PETM carbon data, the researchers found that the models could only explain about half of the warming that Earth experienced 55 million years ago.

The conclusion, Dickens said, is that something other than caused much of the heating during the PETM. "Some feedback loop or other processes that aren't accounted for in these models -- the same ones used by the IPCC for current best estimates of 21st Century warming -- caused a substantial portion of the warming that occurred during the PETM."

Source: Rice University (news : web)

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User comments : 54

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barkster
3 / 5 (14) Jul 14, 2009
The conclusion, Dickens said, is that something other than carbon dioxide caused much of the heating during the PETM.

HA! Wait till I tell the EPA about THIS! Then maybe we can "cap and trade" our greedy excessive use of Oxygen and Nitrogen, too! :-b
Canman
3.9 / 5 (9) Jul 14, 2009
Are our best estimates of projected temps too high, too low, or do we not know which direction they would be flawed?
gmurphy
2.8 / 5 (13) Jul 14, 2009
the title of this article is misleading, the content of the article talks about an event 55 million years ago.
tpb
4.3 / 5 (13) Jul 14, 2009
Chicken-egg again, during the Palaeocene-Eocene, did the CO2 go up because the earth warmed, or did the CO2 go up, and then the earth warmed.
From this article it looks like the earth may have warmed for some unknown reason, and Co2 went up from ocean outgassing.
PPihkala
4.2 / 5 (6) Jul 14, 2009
How about the effect of permafrost buried CO2 and more significantly methane. Methane is more potent gas in terms of temperature rise. And with >5 C of temperature rise, I bet there were no permafrost left, releasing anything under it.
kerry
2 / 5 (5) Jul 14, 2009
@barkster:

Why are you so eager to believe this article as opposed to other global warming articles..?

Props to my university for this study! RICE! FIGHT! NEVER DIE!
ealex
3.9 / 5 (9) Jul 14, 2009
Title is again (Boo Physorg editors) misleading and exagerrates the actual findings.


Azpod
3 / 5 (15) Jul 14, 2009
Title is misleading, yes. But the article itself is a very interesting admission that our current climate models, which predict utter disaster in the next 40-90 years, are flawed at best. And if those models are predicting a PETM-like enormous rise in temperature based on the % rise in CO2 during the PETM, then they're grossly over exaggerated (something I've been saying for a while now.)
dick214
3.1 / 5 (15) Jul 14, 2009
What I see here is the usual Utopian myopic which ignores the virtual loss of fish in the Gulf of Mexico, especially around the mouth of the Mississippi and for many hundreds of miles out to sea in all directions; the vast loss of fish throughout the entire oceanic system; the extensive melting of polar ice and loss of glaciers as well as the gross extinction of a myriad of land species; the devastation of not only potable water but, also of water that can be rendered potable by any feasible economic treatment process; the tremendous reduction of air quality throughout the world to near Soilent Green levels; and the increased dependence upon chemicals to support agricultural plant growth and sustenance. Through all of this and more I frankly don't see any cause for sending up a yippee.
deatopmg
3.1 / 5 (14) Jul 14, 2009
The PETM warming couldn't be due to the sun having a hiccup, for one reason or another, could it? Nah, silly me, what a stupid idea - never mind.

Couldn't possibly put a variable solar output (I.R to X-ray and solar wind) into the failing models.
fleem
2 / 5 (18) Jul 14, 2009
"Since the start of the industrial revolution, carbon dioxide levels are believed to have risen by about one-third, largely due to the burning of fossil fuels."

Blatant lie.

"If present rates of fossil-fuel consumption continue, the doubling of carbon dioxide from fossil fuels will occur sometime within the next century or two."

Blatant lie.

"Doubling of atmospheric carbon dioxide is an oft-talked-about threshold"

Blatant lie.

"and today's climate models include accepted values for the climate's sensitivity to doubling."

Blatant lie.
ormondotvos
3 / 5 (4) Jul 14, 2009
Is there a paleontology of solar output?
CWFlink
3.9 / 5 (11) Jul 14, 2009
GLOBAL FACT: ...almost all of our scientific discoveries for centuries (forever?) have been based on a recurring observation: OUR BEST GUESSES are almost always WRONG.

As scientists, the first and deepest lesson we should have etched into our psyche is that we deal with THEORY and HYPOTHESIS and that FACT only comes afrer repeatable, independently verified experiments over extended periods of time! And even then these "facts" are recognized as only being "accepted fact within the limits of experimental error".

It is astounding to me that we allow our political and emotional sides to go off, half-cocked, when so much is clearly UNKNOWN. We are terrified about today's equivalent of "the population bomb" or the "china symdrome" or the "silent spring" or the "coming ice age".... all predictions of doom that were vastly over dramatized. Observed fact, but here we go doing it all again!

Certainly... we may tomorrow be hit by an unexpected beam of radiation from the sun or a rock wipping this instant from the other side of the sun at half the speed of light. More likely, our earth could up-chuck a major flow of magma, cloud the skys and freeze us all to death.

And frankly, we have little more ability to end global warming through politics than we have of stopping any of those potential disasters!

But as scientists, we MUST demand models that are consistent with the historical record, both short AND LONG, and we must have at least a very healthy level of humility and self criticism before making earth changing predictions....

Unless we are really in it just for the money and we want to get in on the bottom of the "next big thing" .... and THIS is far more likely to be true cause of "global warming" than ANY model published to date!
brianweymes
3.2 / 5 (11) Jul 15, 2009
Wow physorg users have acted surprisingly mature on this article. "Wrong" can mean a lot of things. More than likely the current models used to estimate climate are off by something, how much is a different question, and to what benefit/harm to us, is also an open question. Seeing as this though describes an inconsistency from an event 55 million years ago, it's unlikely to bring anything crashing down. It just means we need to go back, analyse the data and do more science to discover the problem, if this holds up. Not to scream that the models are all wrong while throwing out everything else.
Fakeer
3.4 / 5 (11) Jul 15, 2009
Hmm, everyone in here now is suddenly a geoscientist stating FACTS (which they just read in an article somewhere else that made them feel more comfortable). This speculative topic is far from being fundamental to be argued upon by the plebs. If you are not a scientist but still like to sound off on this subject then you are only a political talking head.

The more important question is not if you believe CO2 is causing warming. The aspect here is more of a personal nature which asks - whether you feel there is a need for mankind to explore alternative sustained energy sources and maybe in the process reduce dependence on fossil fuels.
Egnite
2 / 5 (8) Jul 15, 2009
Yeah, our plants thrive on CO2 and we even put it in our soft drinks so excessive amounts are hardly a problem, just ask coca cola to drop prices and increase production :-O The pollution that comes with burning carbon based fuels are the killers, to our environment and slowly to ourselves. Why ban smoking in pubs when your happy to walk around in the filthy air breathing in second hand fuel fumes? Oh wait, main stream media hasn't told you thats a problem (yet) so who cares eh? Carcinogens are everywhere yet the media has us worrying about the gas we expell when we breath, is that honestly our biggest danger atm? lol, our populations have their heads so far up thier asses they don't even notice they're eating carcinogens in thier convienence foods, then they wonder why cancer is on the rise?

But back to the subject, personally I would trust any climate model as much as I trust the 5day forecast.
toyo
3 / 5 (11) Jul 15, 2009
So what's new?
Whoever thinks that scientists can actually predict anything to do with 'global warming' are sadly self-delusional.
The system that they are trying to 'model' is far, far more complex than any of their simplistic models.
For instance: weather models, that have had far more study done on them, by far more people for a far greater amount of time, and are consequently much more sophisticated, can only predict the weather fairly closely for about 3 days!
Gimme a break!
Johannes
3.8 / 5 (13) Jul 15, 2009
@Fakeer,

Scientific thinking isn't restricted to official scientist. And a fact is a fact even if you belong to the plebs.

But I'm curious; do we all have to be geoscientist to be allowed to talk about this subject or is it alright to be a scientist of another discipline?

Al least you disqualify yourself as a scientist with your social engineering response.

J.
Velanarris
4 / 5 (13) Jul 15, 2009
Well done study. The fact we require a study to state that our knowledge of climate is incomplete is astounding.

As for whether CO2 is causative orcorrelative is outside the scope of the article, as is the warming potential of CO2.

What is inside the scope, and central to the global warming hypothesis is whether the PETM shows evidence of a mechanism (natural or not) that explains warming either with or without carbon chemistry.
tkjtkj
3 / 5 (12) Jul 15, 2009
Title is misleading, yes. But the article itself is a very interesting admission that our current climate models, which predict utter disaster in the next 40-90 years, are flawed at best. And if those models are predicting a PETM-like enormous rise in temperature based on the % rise in CO2 during the PETM, then they're grossly over exaggerated (something I've been saying for a while now.)


I think your thinking is incorrect. The implication of the article is that GW will be WORSE than predicted by 'assumed' CO2 effects, for there is an ADDITIONAL process possibly at work which could augment temperature consequences. This news is bad for the ostrich-people who continue to deny the seriousness of this problem!

E_L_Earnhardt
3 / 5 (10) Jul 15, 2009
The major source of "warming" for our earth is the "SUN"! Highly reflective surfaces could send some of it BACK! Then we could make all the carbon we wanted to and be happy!
iknow
2.8 / 5 (13) Jul 15, 2009
So what's new?

... more sophisticated, can only predict the weather fairly closely for about 3 days!

Gimme a break!


3 DAY prediction? Try that in UK and see what happens. The weather report changes from morning to afternoon..let alone 3 days.

Every singe computer simulation of "GloWarm(tm)" has been so sadly mistaken that they cant ever replicate the historical data with any degree if accuracy... stuff that happened! How can you trust that to predict anything?
3432682
3.1 / 5 (9) Jul 15, 2009
Nice to see a reasonable discussion here.
Velanarris
4 / 5 (12) Jul 15, 2009

I think your thinking is incorrect. The implication of the article is that GW will be WORSE than predicted by 'assumed' CO2 effects, for there is an ADDITIONAL process possibly at work which could augment temperature consequences. This news is bad for the ostrich-people who continue to deny the seriousness of this problem!
No, that's incorrect. The implication of the article is that we don't know enough to make any prediction, be it of disaster or status quo. The article rather clearly states that we haven't enough information on the feedbacks and other mechanisms of the climate system to accurately predict anything.

There's no statement made about the seriousness of the problem or whether it will be worse or better.
Roach
3.8 / 5 (10) Jul 15, 2009
But Vel, LOOK AT THE MAP!!! IT"S ORANGE!!!! THAT"S PROOF!!! WE"RE ALL GOING TO DIE!!!!! AGHHHH!!!!! actually hawaii looks pretty good, it's blue.... or is it a political distribution map? Oh crap.
Shootist
2.9 / 5 (18) Jul 15, 2009
Historically CO2 levels ONLY go up AFTER warming has occurred.

But no one pays attention to history, or the Scientific Method, for that matter.
BobSage
2.8 / 5 (13) Jul 15, 2009
The Earth is a complex adaptive system. Ipso facto, there is no possible way to predict how various inputs will effect its operation. Forget it!

We can't predict the weather a week from now. We'll never be able to do so. Yet Al Gore & Co. predict the weather 40 yeas from now. What a joke.
lengould100
2 / 5 (13) Jul 15, 2009

I think your thinking is incorrect. The implication of the article is that GW will be WORSE than predicted by 'assumed' CO2 effects, for there is an ADDITIONAL process possibly at work which could augment temperature consequences. This news is bad for the ostrich-people who continue to deny the seriousness of this problem!

No, that's incorrect. The implication of the article is that we don't know enough to make any prediction, be it of disaster or status quo. The article rather clearly states that we haven't enough information on the feedbacks and other mechanisms of the climate system to accurately predict anything.

There's no statement made about the seriousness of the problem or whether it will be worse or better.


Actually, the corelation between CO2 and earth surface temperature is explicitly stated in the article. The whole point of it is that when Co2 levels increased at a time 55 million yrs in the past, the temperature increased A LOT MORE than present climate models predict. That's real bad news.
lengould100
1.9 / 5 (18) Jul 15, 2009
The Earth is a complex adaptive system. Ipso facto, there is no possible way to predict how various inputs will effect its operation. Forget it!



We can't predict the weather a week from now. We'll never be able to do so. Yet Al Gore & Co. predict the weather 40 yeas from now. What a joke.

You dummies trying to say we can never ever predict anything in the future because we cannot yet predict weather are pissing me off! How many times do you have to be told. Weather and climate ARE NOT THE SAME THINGS!!! Climate is the AVERAGE of weather across long time periods and large areas. Climate is MUCH more predictable than weather.
SDMike
3 / 5 (11) Jul 15, 2009
An excellent point has been made above. The earth's climate is complex because it is the result of many systems. These systems may each have positive or negative feedback loops. The systems interact with one another. Since any one of these systems is sufficiently complex that it can be a chaotic system, modeling is beyond current capability (see emergent properties). Interacting chaotic systems are certainly beyond the capabilities of available computer modeling.
Velanarris
3.4 / 5 (9) Jul 15, 2009
Conversly, the more thoroughly a system is understood, the less chaotic it appears.

Prime example: electric current.
djr
3 / 5 (6) Jul 15, 2009
It is so interesting - any time there is an article on physorg that may support the notion that we are facing a problem with global warming - people immediately jump all over the article and argue as to why the researchers are wrong - and must be pushing a personal agenda. If the article may appear to question the issue of AGW - same immediate response - but now - isn't great to see objective research that disproves AGW. It is so tiresome. Yes the issue is complex - and the scientist seem to me to be struggling the best they can to understand - and to make predictions to the best of their ability. Climate and weather are certainly different and it is just wrong to suggest that becuz we have trouble predicting tmrws weather - we therefore cannot make any predictions about future climate. Scientific concensus is that we face a serious problem - and it is smart to be worried - and studying that problem carefully. Why can't you deniers just let the scientists do their job - and keep us informed as the data and their understanding develops. If we have a problem - we need to know about it - and the scientists say the data is pretty compelling. If they develop their understanding - and tell us false alarm - we developed alternative energy sources - and took a giant leap forward technologically - where is the problem? Why the need to spread misinformation about current scientific consensus??????
jsa09
4 / 5 (4) Jul 16, 2009
@djr
It is so interesting - any time there is an article on physorg that may support the notion that we are facing a problem with global warming - people immediately jump all over the article and argue as to why the researchers are wrong - and must be pushing a personal agenda. If the article may appear to question the issue of AGW - same immediate response - but now - isn't great to see objective research that disproves AGW. It is so tiresome.

The problem is not the research per se - at least that is the way I see it. The problem is that so many articles quote a study that may or may not indicate that the climate is changing and automatically put that down to Man Made Global Warming without a shred of evidence. If the articles made their point and did not do this there would be less criticism from the deniers.

It is good that people are studying this stuff and models are handy tools (so are some of the modelers). We have to remember that a model is a model of limited value and that the story they tell us has limited benefit.

If we see a few more humble modelers then I think we will see a bit more Kudos to the modelers.

Bitflux
4.2 / 5 (5) Jul 16, 2009
Wow a lot of interesting comments, i see two trends here: Criticism of other people, and the need to play the right and wrong game.
The only way to tell who is wrong or right, is to know the entire truth and i dont know anybody that does that.
I think its great that someone wants to find out how our planet is working and has the courage to take on a task of that immense size. Every bit of information helps build the big picture, criticism makes people withhold information. Whats tricky is the intent behind the information. I've heard a sentence often used in science is "publish or die", is that how we want science to work for us?
chelovek
1 / 5 (1) Jul 16, 2009
There exist another interesting study on the net. If you are interested of it, please type the title "LETHAL KICKBACK OF LARGE-SCALE RENEWABLE ENERGY EXPLOITATION" into any search engine.
Choice
3.7 / 5 (3) Jul 16, 2009
Let's be clear here: this article is saying that our current models don't explain well with what happened 55 million years ago. This means that there is some factor missing from our current models. That factor could still be caused by, triggered, or otherwise related to rising CO2 levels like this: CO2 levels rise>>>factor X occurs (triggered by CO2 levels)>>>temperature rises. Or it could be CO2 levels rise////factor X occurs (unrelated to CO2)>>>temperature rises. Our current models are missing this factor X. This finding suggests neither that CO2 was or was not a contributing cause of PETM, merely that CO2 was not the sole direct explanatory cause ("Using these accepted values and the PETM carbon data, the researchers found that the models could only explain about half of the warming that Earth experienced 55 million years ago.") Cascading causes or other positive feedback loops, possibly triggered by CO2, have not been excluded by this study. Neither has another totally non-CO2 related cause been excluded either. The articles does conclude that half of the PETM is attributable to CO2 levels using our current models.
Egnite
1 / 5 (3) Jul 16, 2009
Please take an hr or two to study this report and all will be explained about what's happening to our climate...and much more.

http://www.projec...2_08.pdf

Some pretty crazy ideas there eh? lol
GrayMouser
2.3 / 5 (9) Jul 16, 2009
You dummies trying to say we can never ever predict anything in the future because we cannot yet predict weather are pissing me off! How many times do you have to be told. Weather and climate ARE NOT THE SAME THINGS!!! Climate is the AVERAGE of weather across long time periods and large areas. Climate is MUCH more predictable than weather.

It may be much more predictable but they haven't been able to predict the last 30 years, or in this case, a period 55 million years ago.

Predicting historic climate is the Holy Grail of climate models because they can be checked against what is already know. If they can't do that they have no basis to claim the ability to predict future weather.

Recent research has shown that better methods for modeling climate (than GCM) may exist:
http://www.wisn.c...ail.html

From my own point, as a software engineer, finding that some people in the US government and the IPCC have admitted that the quality of the climate models is a complete unknown is an indication that they may be starting in the direction of validating the quality of the software before waving the results about like some kind of revelation.
mo411
3.8 / 5 (4) Jul 17, 2009
Unknown? Nah, its that glowing thing in the center of the solar system. This is 101 which I guess is why Al and others missed it...
Nartoon
2.7 / 5 (7) Jul 18, 2009
I am a denier. I deny AGW because I never read any reports of how CO2 could cause the problem, other than believe us. Whereas the opposite view supply many reports from real scientists that appear to disprove the AGW crowd. They are all scientists, but the AGW crowd seem to have much more to gain from their perspective. Why won't any AGW'er ever debate? All they do is show funny slides and movies and say the science is settled -- I don't think a real scientist would ever say that.
iamcrazy
1 / 5 (1) Jul 18, 2009
if we want god to come back we need the world to end. can we please start ww3 already
John_balls
1 / 5 (4) Jul 18, 2009
I am a denier. I deny AGW because I never read any reports of how CO2 could cause the problem, other than believe us. Whereas the opposite view supply many reports from real scientists that appear to disprove the AGW crowd. They are all scientists, but the AGW crowd seem to have much more to gain from their perspective. Why won't any AGW'er ever debate? All they do is show funny slides and movies and say the science is settled -- I don't think a real scientist would ever say that.

Don't you have some cartoons to watch??
snwboardn
5 / 5 (3) Jul 18, 2009
You dummies trying to say we can never ever predict anything in the future because we cannot yet predict weather are pissing me off! How many times do you have to be told. Weather and climate ARE NOT THE SAME THINGS!!! Climate is the AVERAGE of weather across long time periods and large areas. Climate is MUCH more predictable than weather.




So what will be the mean temperature of the earth next year? Since it is so easy to predict...













dachpyarvile
1.9 / 5 (8) Jul 19, 2009


I think your thinking is incorrect. The implication of the article is that GW will be WORSE than predicted by 'assumed' CO2 effects, for there is an ADDITIONAL process possibly at work which could augment temperature consequences. This news is bad for the ostrich-people who continue to deny the seriousness of this problem!



No, that's incorrect. The implication of the article is that we don't know enough to make any prediction, be it of disaster or status quo. The article rather clearly states that we haven't enough information on the feedbacks and other mechanisms of the climate system to accurately predict anything.



There's no statement made about the seriousness of the problem or whether it will be worse or better.





Actually, the corelation between CO2 and earth surface temperature is explicitly stated in the article. The whole point of it is that when Co2 levels increased at a time 55 million yrs in the past, the temperature increased A LOT MORE than present climate models predict. That's real bad news.


We already know you do not understand the science, len. Proof of that was in your comments in another thread that use of Ethanol would not reduce CO2 levels.

1000 years ago the Arctic climate was at least 4° to 5°C higher than today, and perhaps more. We know this because of a number of findings in Greenland (deep graves dug 1000 years ago with hand tools which are frozen solid today, historical records of people swimming in waters off Greenland whereas temperatures today would assure a quick hypothermic death, species of fish near the shores that are not present today, species that do not like water as cold as at present, crop pollens, etc.) and in places ranging from Alaska to Norway.

There was not a massive melting of the GIS or flooding coastlines like the gloom and doom Gorians say will happen. And, yet, CO2 was not at the root of the rise in temperatures 1000 years ago, or even 2000 years or so ago during the Roman Warm Period.

The article is right. We do not know enough to make the sorts of gloom and doom predictions that are being made, based on faulty models and misreading of the data, not to mention failure to look into the facts of history and prehistory.
KCD
2 / 5 (4) Jul 19, 2009
Well. I do agree to the article. Earth HAD experienced global warmings and it is repeating.

MrGhaz
not rated yet Jul 19, 2009
Over the past 40 years, the Earth%u2019s average temperature has risen by 0.2 to 0.3°C. In Malaysia, the temperature is rising by about 0.18°C every decade.
Birger
5 / 5 (2) Jul 20, 2009
Wow a lot of interesting comments, i see two trends here: Criticism of other people, and the need to play the right and wrong game.
The only way to tell who is wrong or right, is to know the entire truth and i dont know anybody that does that.

I absolutely agree. Climate is much more "chaotic" than, say, the orbital mechanics of the Solar system. I do not find it surprising that it is hard to come up with a computer model that can explain the changes 55 million years ago, based on our incomplete knowledge of how the climate worked back then.
For instance, since we obviously lack exact measurements of trace gasses or seasonal temperature variations, we have to rely on "proxy" measurements of preserved indirect traces that do not necessarily have a 1:1 relation to what we really want to measure. Getting the CO2 level or temperature wrong to the extent mentioned in this article (as opposed to being wrong by a factor of 10) is probably no disgrace.
Being aware of the flaw is in itself exciting news, now climate modellers can go ahead and search for the subtle causes that has thrown the existing paleoclimate models off track. The experience can then be applied to models of the current climate.
PaulLove
5 / 5 (2) Jul 20, 2009
So the climate seems cyclical we've been hotter and colder, my home's location has been under glaciers repeatedly. Are humans responsible for global warming certainly 6 billion of us radiating at 98.6 degrees has to have an effect. I'm just sort of wondering who the fellow was who ran in front jammed a flag in the sand and said this dynamic system should move no further than this.
Duude
1.7 / 5 (6) Jul 21, 2009
Anyone with half a brain realizes that when scientists take a hard stand without clearly enough complete data, they are only using half a brain. The arrogance of man to assume that he has a handle on the amount of carbon released naturally from volcanoes even when not particularly active whether above or below the ocean. How arrogant of man to assume that the solar cycles which we have tracked for years have nothing to do with climate change. How arrogant for scientists to assume that an increase in carbon will necessarily raise temperatures at all. How arrogant of scientists to even assume they actually fully understand the thaw and freeze cycle of the polar caps through history considering that they haven't been tracking them very long, and admit now they're uncovering substantial errors in their calculations that could still be errors of their errors. How arrogant of scientists to have once scoffed at theories of gravity and to have held steady for so long with the idea that the Earth was flat.
Damon_Hastings
2.6 / 5 (5) Jul 21, 2009
The below is a response to much earlier comments that just annoyed me too much to ignore.

Guys, this article is saying that human-induced global warming could be *worse* than we thought. It's *not* an argument against human-induced global warming. From the article:

Some feedback loop or other processes that aren't accounted for in these models -- caused a substantial portion of the warming that occurred during the PETM.

In other words, there could be more feedback loops that will make global warming even worse than we thought. This says nothing about humans being blameless. Please read the article before commenting on it.

As for the PETM, yes, the warming preceded the CO2 increase, and yes, that means the PETM was not initiated by CO2. And no, that does not prove that global warming today is caused by something other than CO2. Geez.
Velanarris
3.7 / 5 (3) Jul 21, 2009
The below is a response to much earlier comments that just annoyed me too much to ignore.

Guys, this article is saying that human-induced global warming could be *worse* than we thought. It's *not* an argument against human-induced global warming. From the article:

Some feedback loop or other processes that aren't accounted for in these models -- caused a substantial portion of the warming that occurred during the PETM.


In other words, there could be more feedback loops that will make global warming even worse than we thought. This says nothing about humans being blameless. Please read the article before commenting on it.

As for the PETM, yes, the warming preceded the CO2 increase, and yes, that means the PETM was not initiated by CO2. And no, that does not prove that global warming today is caused by something other than CO2. Geez.

It also states that our current models, the only evidence for AGW, do not take all factors into account. It states our knowledge of the climate system is lacking. And it makes no statement about warming and CO2 relationships outside of the basis GHG statement.

The only thing the article says is "we don't know".

Which is exactly what our point is. Read all the comments before commenting.
MorganW
5 / 5 (1) Jul 27, 2009
Will someone please just tell me once and for all, what the damn temperature is SUPPOSED TO BE for God's sake???
It goes up and it goes down - can't we just f***ing deal with it? I'm so goddamn tired with all this back and forth B.S. from both sides! NONE of you has a f***ing clue one way or another. The hubris in thinking that we can exist outside of our environment or adapt it to whatever arbitrary climate we think is "perfect" is insane.
jsa09
not rated yet Sep 09, 2009
the temperature should be 75 degrees and it should rain at night only on Wednesday and Thursday. Many people will agree with me on this and you will find that many people are willing to drop stuff into clouds to make it rain because they feel that it should rain when they want it to.

You will find that many people are happy or at least willing to drop stuff into the oceans or the upper atmosphere just to cool the planet down or warm it up depending on what part of nature they don't like.

I remember going to church groups when I was young and hearing that man has the god-given right to do whatever he wants.
Velanarris
1 / 5 (1) Sep 10, 2009
I remember going to church groups when I was young and hearing that man has the god-given right to do whatever he wants.
Except everything the church doesn't want him to do.