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Blog: Science Report: CO2 Not Responsible for Past Warming
Michael Asher (Blog) - October 17, 2007 3:42 PM
Print E-mail del.icio.us 147 comment(s) - last by Andy35W.. on Nov 14 at 8:10 AM

New Research links retreating ice sheets to climate change -- not the other way around.
Major new study disputes primary link to greenhouse gas warming

Its the strongest evidence for the Greenhouse Gas theory of global warming -- that warm periods in the earth's past were typically accompanied by rises in atmospheric carbon dioxide.  But that evidence is under serious attack, from new research funded by the U.S. National Science Foundation.

The research team, led by Paleoclimatologist Lowell Stott, demonstrated CO2 levels after the last Ice Age started to rise some 1,300 years after the warming began.  According to Stott, earlier researchers had cause and effect reversed -- CO2 increases were the result of warming, and not the original cause.  Stott's paper is not the first to show CO2 rises followed warming trends, but it is one of the most detailed and thorough rebuttals of the linkage.

The work comes hot on the heels of other research downgrading CO2's importance in climate change.  Earlier this year, the Belgian Royal Meteorological Institute issued a study saying CO2 effects had been "grossly overstated."  Dr. Steven Schwartz of Brookhaven National Labs concluded that CO2-based warming had been overstated by some 400%, and a pair of Chinese researchers used mathematical modeling to demonstrate the majority of current warming was natural in origin.

Stott's findings are important for two reasons.  First, they directly challenge the correlation between CO2 and warming.  As Stott himself points out, CO2 is still likely a contributor to climate change, but its role needs to be reevaluated.

The results also weaken the belief that present-day atmospheric CO2 increases must be anthromorphic -- human-induced.  Stott's model showed how the warming generated changed ocean conditions, which then generated massive releases of CO2 from the ocean into the atmosphere.   As natural CO2 sources still constitutes more than 97% of all emissions, this may not come as much of a surprise.

But if CO2 didn't cause the warming, what did?  Stott's model links the forcing to periodic changes in the Earth's orbit which increase solar radiation over Antarctica.  This eventually causes ice sheet retreat, which lowers ocean albedo, reflectivity.  Additional warming is generated, a feedback effect which over 1,000 or more years, transports heat via deep-sea currents to the Northern Hemisphere.  The model also explains why surface measurements of solar insolation fail to correlate with warming ... the heat transport process is very slow, and thus surface warming lags centuries behind changes in solar output.

Stott is a professor at the University of Southern California, and a reviewer for the United Nations' Intergovernmental Panel on Climate Change. 

The Nobel Foundation recently announced the IPCC as a corecipient of the 2007 Nobel Peace Prize.

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This is not new!
By pliny on 10/18/2007 8:51:01 AM , Rating: 2
It is just not true to say that AGW implies a belief that past warmings were caused by CO2 forcing. Nor is the observation that CO2 lagged warming in past deglaciations new. The IPCC report (AR3) of 2001 had this to say
quote:
From a detailed study of the last three glacial terminations in the Vostok ice core, Fischer et al. (1999) conclude that CO2 increases started 600 ± 400 years after the Antarctic warming.
http://www.grida.no/climate/ipcc_tar/wg1/072.htm#2...




RE: This is not new!
By masher2 (blog) on 10/18/2007 9:04:22 AM , Rating: 2
You left out the most important part of that quote:

quote:
However, considering the large uncertainty in the ages of the CO2 and ice (1,000 years or more if we consider the ice accumulation rate uncertainty), Petit et al. (1999) felt it premature to ascertain the sign of the phase relationship between CO2 and Antarctic temperature at the initiation of the terminations. In any event, CO2 changes parallel Antarctic temperature changes during deglaciations.
This shows the IPCC clinging to the assumption that CO2 contributed greatly to ending those ice ages. This new study, however, shows the action was primarily over before CO2 rose substantially.


RE: This is not new!
By pliny on 10/18/2007 9:47:42 AM , Rating: 2
They are just saying that the 1999 evidence has enough error that you can't be certain of the phase relation. This isn't "clinging", because they never asserted the relation that you say they are clinging to. And they say CO2 "parallels" temperature, which is true. That is a neutral statement - doesn't say whether it is before or after.


RE: This is not new!
By LogicallyGenius on 10/20/07, Rating: 0
RE: This is not new!
By TomZ on 10/18/2007 9:06:33 AM , Rating: 3
I don't think you're paying very close attention to the AGW rhetoric. For example, in An Inconvenient Truth, Al Gore discusses at great length about past history rises in CO2 that "caused" past temperature rises. Then he goes on to talk about our current "skyrocketing" CO2 levels, saying that we are causing those, and therefore, we are causing the current global warming.

In addition, I just have to laugh at your statement in another post where you are basically saying that this time the temperature rise is different, i.e., there is a different mechanism in play now compared to other times in history. Obviously you are implying that humans are causing the current rise, but you completely ignore the fact that the current warming trend started some 250 years ago before humans had the technology to cause any sort of significant rise in CO2 or other GHGs.


RE: This is not new!
By pliny on 10/18/2007 9:24:57 AM , Rating: 1
I'm not sure what Al Gore says - he may have mis-stated it. I believe that this was one of the areas where the British judge said that he was out of line with the mainstream. I do know that scientists do not believe that past warmings were CO2 driven. I do imply that humans are causing the current rise, due to the 150 Gt of carbon we have put into the atmosphere. That is the CO2 forcing. It may be that there was some small temperature rise 250 years ago caused by something else.


RE: This is not new!
By masher2 (blog) on 10/18/2007 9:29:31 AM , Rating: 1
> "I do know that scientists do not believe that past warmings were CO2 driven"

From IPCC 2001 (your own link, above):

quote:
This is consistent with a significant contribution of these greenhouse gases to the glacial-interglacial changes...


RE: This is not new!
By pliny on 10/18/2007 9:39:01 AM , Rating: 2
To complete the quote:
quote:
This is consistent with a significant contribution of these greenhouse gases to the glacial-interglacial changes by amplifying the initial orbital forcing (Petit et al., 1999).

ie something else (orbital forcing) started the warming, and the gases that were driven out by warming provided positive feedback which caused further warming. but that is feedback, not a forcing. And as they (IPCC) say, that is consistent with a delayed CO2 rise, observed by both Petit (1999) and Stott.


RE: This is not new!
By masher2 (blog) on 10/18/07, Rating: -1
RE: This is not new!
By pliny on 10/18/2007 10:05:51 AM , Rating: 3
No, Stott is careful about timing, he says:
quote:

nor can its early onset between 19-17 ka B.P. be attributed to CO2 forcing
. That is consistent with the possibility of later amplification.

The earlier result was between 200 and 1000 years delay; Stott says 1300 (with no error limits). Not very much difference there.


RE: This is not new!
By pliny on 10/18/2007 10:14:39 AM , Rating: 2
Incidentally, the fact that we're trying to glean the IPCC's view from a single non-committal paragraph buried deep in the AR3 is a clear indication that it is not true that
quote:
Its the strongest evidence for the Greenhouse Gas theory of global warming -- that warm periods in the earth's past were typically accompanied by rises in atmospheric carbon dioxide.

If that were their strongest evidence, they would be much more upfront with it!


RE: This is not new!
By masher2 (blog) on 10/18/2007 10:39:18 AM , Rating: 1
> "If that were their strongest evidence, they would be much more upfront with it! "

If you believe they have stonger evidence for CO2's role in forcing, then put it forth here. A simple radiative forcing calculation doesn't give rise to anywhere near the level of warming the IPCC predicts.

The only evidence for CO2's role in climate change is the correlation in the geologic record, and the projections of GCM models. Remove the geologic correlation, and that leaves only the GCMs, which are based on thousands of ad-hoc parameters, and have failed utterly in predictive ability.


RE: This is not new!
By pliny on 10/18/2007 10:58:41 AM , Rating: 2
No the primary evidence for CO2's role in climate change is the greenhouse effect. You can calculate, by a fairly simple 1D analysis, the IR heat absorbed. And you can verify, by looking at the satellite-measured spectrum of outgoing IR, the radiation that has been absorbed. Comes to roughly 2 W/m2. Arrhenius could see that in 1896. And sure, you then need to adjust for clouds, aerosols, feedback etc, which is where the GCM's come in.

There were essentially no pre-instrumental temperature or CO2 estimates to correlate in the 1980's, when AGW gained widespread scientific acceptance, leading to the Kyoto meeting.


RE: This is not new!
By masher2 (blog) on 10/18/2007 11:13:33 AM , Rating: 1
> "the primary evidence for CO2's role in climate change is the greenhouse effect. You can calculate, by a fairly simple 1D analysis, the IR heat absorbed"

Which is what I said. However, that calculation results in an expected rise of only 0.6 - 1.0 degrees for the first doubling of CO2. The IPCC predicts 2.5 degrees, possibly more.

The difference is anticipated feedback effects, which are extrapolated from GCM models, whose parameters derived from "best guess" estimates of climate response, taken largely from analysis of the Earth's response to past conditions. Where else would they come from?

If one removes the geologic record from the equation, a simple radiative forcing delta calculation (aka "greenhouse effect") leads only to a minor degree of warming, most of which we've already experienced.


RE: This is not new!
By pliny on 10/18/2007 6:10:35 PM , Rating: 2
Yes, it's true that positive feedback amplifies the GHG effect by a factor of 2 or more, and that ultimately the best estimate of this factor comes from the climate history. But that has little to do with what is discussed here. The strongest feedback by far is from water vapor. More heat, more vapor, which is a GHG, then more heat. The feedback role (as opposed to the driver role) of CO2 is minor in comparison.


RE: This is not new!
By masher2 (blog) on 10/18/2007 6:50:43 PM , Rating: 2
> "The feedback role (as opposed to the driver role) of CO2 is minor in comparison. "

You might want to inform the IPCC of your theories, as they clash strongly with their own opinion. Again, from your earlier link:

quote:
This is consistent with a significant contribution of [CO2] to the glacial-interglacial changes by amplifying the initial orbital forcing


RE: This is not new!
By pliny on 10/18/2007 7:43:32 PM , Rating: 2
No need to do that - they know!
quote:
Water vapour feedback continues to be the most consistently important feedback accounting for the large warming predicted by general circulation models in response to a doubling of CO2. Water vapour feedback acting alone approximately doubles the warming from what it would be for fixed water vapour (Cess et al., 1990; Hall and Manabe, 1999; Schneider et al., 1999; Held and Soden, 2000). Furthermore, water vapour feedback acts to amplify other feedbacks in models, such as cloud feedback and ice albedo feedback.

http://www.grida.no/climate/ipcc_tar/wg1/268.htm


RE: This is not new!
By grenableu on 10/18/2007 11:49:23 AM , Rating: 2
Even my son's 8th-grade science book shows a graph linking CO2 to previous warming of the Earth. You can't toss this study away that lightly.


RE: This is not new!
By murphyslabrat on 10/18/2007 4:32:17 PM , Rating: 2
People believed the earth to be flat for hundreds of years, and they even taught it to kids. Does that give any cause to believe it true?


RE: This is not new!
By TomZ on 10/18/2007 4:55:02 PM , Rating: 2
Luckily my kids are too young to learn about this stuff in school, otherwise I'd have to go in there and kick some teacher @ss if I came across something like AGW in their textbooks. LOL.


RE: This is not new!
By pliny on 10/18/2007 6:19:42 PM , Rating: 2
Well, I can't check that textbook. But I can check the IPCC 2007 summary doc, which is here:
http://www.ipcc.ch/SPM2feb07.pdf
I can find no trace of this alleged fundamental argument that past warmings were driven by CO2. Can anyone?


RE: This is not new!
By masher2 (blog) on 10/18/2007 6:52:43 PM , Rating: 2
> "I can find no trace of this alleged fundamental argument that past warmings were driven by CO2. Can anyone? "

You won't find any fundamental arguments of any sort in that link. The IPCC "Summary for Policymakers" is written by politicians for politicians, and contains no science or underlying arguments. It just states conclusions, without attempting to explain how it arrives at them.


RE: This is not new!
By pliny on 10/18/2007 7:40:03 PM , Rating: 2
Well, where can we find it? If, as you say, "Its the strongest evidence for the Greenhouse Gas theory of global warming", then some quotable scientist must be asserting it somewhere. I looked for places in the IPCC AR3 "scientific basis" http://www.grida.no/climate/ipcc_tar/wg1/index.htm and this noncommittal reference that we've discussed was all I could find. And the AR3 has plenty of other evidence.


RE: This is not new!
By pliny on 10/19/2007 12:14:07 AM , Rating: 3
More details here. Stott discusses this work on his website here:
http://earth.usc.edu/~stott/ProjectsFolder/Project...
quote:

Climate model simulations utilizing the history of greenhouse gases, ice-sheet orography and orbital forcing demonstrate that austral spring insolation combined with sea ice-albedo feedbacks were key factors responsible for this warming. Atmospheric CO2 was a contributing factor but would not have been the trigger that initiated deglacial warming.

quote:

Clearly CO2 forcing was a contributing factor to the warming, but was not responsible for much of the warming that took place globally.


So Stott and the IPCC(2001) agree - something else started it, and later CO2 feedback may have been a factor.


OK but?
By Misty Dingos on 10/17/2007 4:19:00 PM , Rating: 5
Does this mean that Al is going to give back the Nobel Peace Prize? After all he has done is scared the crap out of a bunch of kids. Not a very peacefull thing to do.




RE: OK but?
By jskirwin on 10/17/2007 4:30:34 PM , Rating: 5
quote:
Does this mean that Al is going to give back the Nobel Peace Prize?


Too late. He already used his half to pay last month's electric bill.


RE: OK but?
By porkpie on 10/17/2007 4:43:06 PM , Rating: 5
If that post doesn't deserve a +6, then nothing does.


RE: OK but?
By murphyslabrat on 10/18/2007 4:33:42 PM , Rating: 4
Whee I'm gonna reply and get lots of up-rates, too!


RE: OK but?
By TomZ on 10/18/2007 4:55:42 PM , Rating: 3
Ride the wave!


RE: OK but?
By murphyslabrat on 10/22/2007 10:12:20 AM , Rating: 2
Holy cow, I didn't think anyone would actually uprate me!


RE: OK but?
By johnsonx on 10/17/2007 6:30:37 PM , Rating: 2
I posted this once before, but again I find it fitting:

http://www.paulshanklin.com/audio/p_spastic17.mp3


RE: OK but?
By murphyslabrat on 10/18/2007 4:38:16 PM , Rating: 2
Thanks a lot, I just got scolded for being too loud in the library. That down-right slanderous, and I couldn't stop laughing.


RE: OK but?
By MrPickins on 10/18/2007 5:53:52 PM , Rating: 2
Wish I could "6" ya!


Wait a second...
By clovell on 10/17/2007 4:43:32 PM , Rating: 3
If...
quote:
The research team, led by Paleoclimatologist Lowell Stott, demonstrated CO2 levels after the last Ice Age started to rise some 1,300 years after the warming began.
than how do we get to...
quote:
As Stott himself points out, CO2 is still likely a contributor to climate change, but its role needs to be reevaluated.
I mean - how can A contribute to B if A comes after B ?

Or are we talking about climate change in a broader sense than simply warming?




RE: Wait a second...
By masher2 (blog) on 10/17/2007 4:57:48 PM , Rating: 3
Stott was implying that CO2 is still likely a contributor to warming as a feedback process, just not a direct forcing agent. In other words:

Warming occurs -> releasing more CO2 -> causing additional warming.


RE: Wait a second...
By clovell on 10/17/2007 5:08:35 PM , Rating: 2
Ah, that makes sense. So, assuming that's the case - wouldn't that change the dynamics of the AGW debate significantly? I mean, the CO2 is being released naturally - far in excess of what we have control over. Furthermore, it's no longer the driving force behind the warming.

The question would now become, if CO2 isn't the root cause of the warming, then what is? This paper indicates that changes in the Earth's orbit cause the warming, and that's not something we can really change. So...?


RE: Wait a second...
By onelittleindian on 10/17/2007 5:22:26 PM , Rating: 2
quote:
wouldn't that change the dynamics of the AGW debate significantly? I mean, the CO2 is being released naturally - far in excess of what we have control over
You hit the nail on the head there. And thats exactly why you won't see CNN's "science/environmental" reporters covering this story.


RE: Wait a second...
By TomZ on 10/17/2007 7:25:52 PM , Rating: 2
Damn right about that - because if humans are not causing global warming, then the whole political movement goes down the tubes. How can the environmentalists try to control our lives without such a fear factor in play? On to the next crisis!


RE: Wait a second...
By Kuroyama on 10/18/2007 3:50:47 AM , Rating: 2
Actually, they do cover a fair number of these stories, just their spin is always the opposite of Masher's.


RE: Wait a second...
By chsh1ca on 10/18/2007 3:22:18 PM , Rating: 2
It's sad that reporting scientific findings requires spin in either direction.


correlation?
By Kuroyama on 10/17/2007 4:30:09 PM , Rating: 2
quote:
First, they directly challenge the correlation between CO2 and warming.

I think you mean they challenge causality, as in CO2 causes warming. It sounds like there is still a correlation, apparently between (temp.change+1300years) and CO2 changes.




RE: correlation?
By masher2 (blog) on 10/17/2007 4:59:53 PM , Rating: 2
Good point, but the research does in a way challenge the correlation as well...or rather, supplants it with a new corrrelation, biased with a strong latency factor.


RE: correlation?
By JasonMick (blog) on 10/17/2007 5:43:04 PM , Rating: 2
There's no latency factor, I think what you wanted to say is that for this time period it appears to reverse the correlation.

A latency factor would imply CO2 was still causing the warming, just later than expected.

But you are correct that it does attempt to supplant it! =D


RE: correlation?
By masher2 (blog) on 10/17/2007 6:21:19 PM , Rating: 2
> "a latency factor would imply CO2 was still causing the warming"

No, because correlation does not imply causation. There is a correlation between CO2 and temperature rise. But due to the latency, its clear CO2 is not the causative agent -- the temperature rise itself is.


RE: correlation?
By chsh1ca on 10/18/2007 3:27:18 PM , Rating: 2
The only clear thing any of the recent research has shown us is that we lack sufficient data to accurately state anything when it comes to climate change. Maybe in 50-250 years we'll have a better idea, but right now it's a big question mark.


RE: correlation?
By murphyslabrat on 10/18/2007 4:48:40 PM , Rating: 2
The study does talk about a latency factor, that CO2, while not the agent of change, is a product of warming as well as a catalyst for warming. So, the warmer it gets, the more CO2 is released, and the larger the affect of the CO2 population is on the rising temperatures.

a causes b, which results in c, and c affects b.

a=change in orbit, b=changing temperatures, c=CO2 population.


ocean warming
By duesd001 on 10/17/2007 10:18:18 PM , Rating: 2
The ocean is a major reservoir for CO2, until it heats up then it very quickly loses its ability to hold dissolved gases. It would be interesting to know if there was a pH change in the ocean which coincided with the rise in deep ocean temperatures. Does the temp continue to rise as CO2 is released from the ocean? Does it speed up? Slow down? Are there any other atmospheric phenomena that could explain the temperature changes? It is after all the oceans that make our planet livable, by slowing and moderating changes in temperature and atmospheric composition. Like most complex arguments, proponents on both sides over simplify and distort small pieces of scientific research to support their claims.
Some facts:
Climate change is happening
We don't know how much fossil fuel we have left
we know that much of the fossil fuels that are left will be extremely expensive to extract
Everything that we do everyday is tied to our use of fossil fuels
Change is slow
$10 per gallon for gas will greatly disrupt our economy and food supply

Changes in our lifestyles and habits will happen: Slowly and on our terms or dictated by a situation out of our control.
Daniel Duesing




RE: ocean warming
By barclay on 10/17/2007 11:34:03 PM , Rating: 2
> "We don't know how much fossil fuel we have left
we know that much of the fossil fuels that are left will be extremely expensive to extract"

While this may be true of oil, coal appears to be stable in terms of extraction expenses and will likely continue to be for the next century or more.
http://www.eia.doe.gov/cneaf/electricity/epm/epm_s...

In either case, the real question is, should market forces or government set the pace of migration away from fossil fuels?

If it is just a matter of energy needs, the market is ideal-- alternative sources of energy will be increasingly used as the price of existing sources increase in cost. It is efficient and smooth.
In order for government to be justified in interfering, two questions need to be answered:
1. Do fossil fuels produce negative externalities (reworded -- does the CO2 released from fossil fuels negatively affect the earth's climate)?
2. Do the costs associated with a worst climate outweigh the costs associated with accelerating the move away from fossil fuels?


RE: ocean warming
By andrinoaa on 10/18/2007 12:30:23 AM , Rating: 2
If you rely on market forces for everything, we would be in a very bad state. The market cannot fix everything! Yes , I repeat, the market cannot fix everything. The market is a tool of human organization. Thus it has flaws.
We subsidise antisocial behaviour ie mining asbestos. If the market was perfect, the cleanup costs would be included in the price of fuel but it insn't!
Us humans need to determine outcomes not let the "market" have its whims. The market is there to SERVE US not to be the ultimate goal. Individual freedom is good, but some times we come together to form government and form laws because we know that without limitations we are like children who will self destruct ie "Lord of the flies".
William Golding was more insiteful of human behaviour then Ms Bronte


RE: ocean warming
By Kuroyama on 10/18/2007 1:02:08 AM , Rating: 2
Actually, I think his comments were pretty fair as he acknowledged the existence of externalities, and only left open the issue of whether these are sufficient to justify government intervention.

The best role for government is to add in a tax equal to the expected cleanup costs, and then put that money in some sort of trust fund to pay for it when the time comes. Likewise for other negative externalities. But then be fair and at least for coal factor in some amount of benefit for decreased reliance on overseas oil supplies. Once the externalities are accounted for then let the market figure out the rest.

Alas, politics always messes with everything. For Republicans "tax" is a nasty swear word, while for Democrats oil and coal companies are evil and should be punished, so alas I have no faith that more than a feeble attempt at a proper accounting for externalities can ever be implemented.


Things never change...
By Captain Orgazmo on 10/17/2007 6:31:34 PM , Rating: 4
This whole debate, Al Gore and the zealots vs. reason, reminds me of an old quote about human nature, from the novel Shirley by Charlotte Bronte (author of Jane Eyre):

"Note well! Whenever you present the actual, simple, truth, it is somehow always denounced as a lie: they disown it, cast it off, throw it on the parish; whereas the product of your own imagination, the mere figment, the sheer fiction, is adapted, termed pretty, proper, sweetly natural: the little spurious wretch gets all the comfits - the honest, lawful bantling all the cuffs. Such is the way of the world..."

How well it fits today's issues, considering it was written in 1849. People are more willing to accept Al Gore and David Suzuki's extravagant fiction, rather than dull old science. Human nature is so predictable, so illogical... too bad Spock can't run for president (not born in the USA).




RE: Things never change...
By andrinoaa on 10/18/2007 12:12:14 AM , Rating: 1
Why is it that we believe once peice of science yet discard another? How much evidence do some people need before it hits them in the head?
Marine scientists in the Great Barrier Reef have discovered the the ocean is becoming acidic: carbonic acid! It is absorbing more co2. This may seem to go against the flow but is a consequence of lots of CO2 in the atmosphere. There is a balance of the CO2 content in the atmosphere and in the oceans (don't know what the specific ratio is ). If more is released into the atmosphere, to maintain the balance, more is absorbed by the oceans. Do you guys who think us humans have no effect whatsoever know what will happen if the oceans become too acidic? My info suggests basic food stocks , ie plankton , will become scarce and so will everything above in the food chain.
I for one think that we could be infor a double wammy.
Every peice of evidence is dismissed, scientists who have studied these things for long periods are dismissed as "the green industry" and zealots. Canarys have never had it so bad!
By all means, disagree, but please , introduce your 20years of research. Get the facts straight. The reason we have a global warming scenario at the moment is that lots of independant scientific research units have come to similar conclusions.. Are they all wrong? Have we got a generation of shizzen housen scientists?
PS. Charlotte Bronte wasn't a scientist and for every wise tale there is an opposite - think before you leap, he who hesitates is lost, which one is right?
Captain orgazmo, take your hand off it!


RE: Things never change...
By Captain Orgazmo on 10/18/2007 2:03:45 AM , Rating: 2
Actually, people who present statistics that do not go with the popular belief of man-made global warming are the ones who are dismissed and called "deniers". I challenge you to "introduce your 20 years of research". Then compare it to the last 40 years of research that suggested we were in for another ice age.

I'm pretty sure I'm wasting my time writing this, as your English is so terrible I'm not even sure if you were agreeing or disagreeing with my post. If your first language is not English, I apologize, but if it is, please attempt to organize your thoughts before vomiting them onto this website.


Quote by Scott
By howtochooseausername on 10/18/2007 2:19:34 PM , Rating: 2
I found the following quote by Scott:

quote:
“I don’t want anyone to leave thinking that this is evidence that CO2 doesn’t affect climate,” Stott cautioned. “It does, but the important point is that CO2 is not the beginning and end of climate change.”


I think its important to understand that this paper does not say that today's warming is not caused by Greenhouse Gases. Rather it only says that in the past the warming that the earth experienced appears not to have been immediately caused by CO2 in the atmosphere. I hope everyone understands that distinction.




RE: Quote by Scott
By TomZ on 10/18/2007 2:33:36 PM , Rating: 2
But today's belief in AGW is explained as a direct causal relationship between CO2 and global warming, based on (misinterpreted) historical data. So this research begins to take apart one of the key "assumptions" of the AGW belief system. I hope that is clear, too.


RE: Quote by Scott
By murphyslabrat on 10/18/2007 5:04:17 PM , Rating: 2
No, it is not talking about "only in the past" it is saying that CO2 does strongly influence the temperature, but it is not solely the product of man-made (not woman-made either) gases. It is saying that there is a natural cycle that affects the CO2 population and temperatures, and that it has nothing to do with humans.


Minor mistake
By DeepBlue1975 on 10/19/2007 9:22:51 AM , Rating: 2
quote:

Its the strongest evidence for the Greenhouse Gas theory of global warming


Should be "It's", not "Its".

PS: Nice article!




Fear!
By Googer on 10/19/2007 10:40:16 PM , Rating: 2
This just goes to prove how much of a Fear Mongerer Al Gore really is and he is doing it for capital gains in the form of scaring you in to buying "carbon credits" from a company he owns and in to paying to see his propaganda films.




Word switcharoo
By EidolWays on 10/20/2007 6:44:57 PM , Rating: 2
It's worth briefly noting that "anthromorphic" isn't a word. The properly spelled word, "anthropomorphic", isn't appropriate in this case either because it means "human-shaped." The right word, and the word used in a lot of the comments here, is "anthropogenic", meaning "human-born."




By Andy35W on 11/14/2007 8:10:31 AM , Rating: 2
Though that theory seems to being debunked somewhat

http://news.bbc.co.uk/2/hi/science/nature/7092655....

One of the problems climate change skeptics have is they cannot settle on another theory that causes it. People who quote their work don't seem to care as long as it debunks humans being the cause.




vote one for graft!
By GlassHouse69 on 10/18/2007 6:57:38 PM , Rating: 1
It is amazing what 10 billion dollars in payoffs can accomplish!

Go Bush!




Interesting...
By JasonMick (blog) on 10/17/07, Rating: -1
RE: Interesting...
By TomZ on 10/17/2007 4:30:19 PM , Rating: 2
quote:
I don't see this new study as conclusive proof of anything

The point isn't to prove anything - the objective is to report on another study that is helping to deconstruct the myth of human-induced global warming.


RE: Interesting...
By JasonMick (blog) on 10/17/07, Rating: -1
RE: Interesting...
By TomZ on 10/17/2007 4:46:56 PM , Rating: 3
I disagree. At least one element of the study - the observation that CO2 rise happens some 1300 years after the temperature rises - helps to disprove the assertion that CO2 rise has in the past led to (caused) higher global temperatures. This causation is a core belief in the AGW mythology.


RE: Interesting...
By JasonMick (blog) on 10/17/07, Rating: -1
RE: Interesting...
By TomZ on 10/17/2007 5:29:07 PM , Rating: 3
quote:
Do you understand what I mean?

Yes, I understand, but I also disagree. The conditions don't have to be identical, because the relevant part of the study IMO is that CO2 rise lags temperature rise by 1300 years. This indicates that, for the period of the study at least, that it is an error to conclude that CO2 rise causes global warming based on historical data.


RE: Interesting...
By JasonMick (blog) on 10/17/07, Rating: -1
RE: Interesting...
By porkpie on 10/17/2007 5:55:52 PM , Rating: 3
quote:
This scenario is not relevant to modern warming
Which part do you not understand? The study is relevant because past warming has been used as evidence to blame modern warming on CO2.

Now, there are only two possibilities. Either past conditions were similar to modern ones or they weren't.

If they WERE similar, then modern warming is probably happening for the same reason as the past.

If they WEREN'T similar, then you can't use past events to justify blaming CO2 on modern warming.

You keep trying to reverse things. The study isn't proving anything. Its REMOVING proof from those who blame GHGs based on past events.


RE: Interesting...
By TomZ on 10/17/2007 7:12:37 PM , Rating: 4
quote:
You keep trying to reverse things. The study isn't proving anything. Its REMOVING proof from those who blame GHGs based on past events.

Thank you - that is the same point I'm trying to get across.

And shame on the downraters of my posts above - if you disagree, please speak up. It is pretty lame to just rate me down without even understanding the discussion. Jason's pretty wrong here, and I'm the one getting downrated.


RE: Interesting...
By drebo on 10/17/07, Rating: -1
RE: Interesting...
By TomZ on 10/17/2007 8:47:27 PM , Rating: 2
Yes, the "proof by repeated assertion" method.


RE: Interesting...
By DNAgent on 10/18/2007 9:58:50 AM , Rating: 5
Do you honestly believe that "conservatives" never use that tactic? Please...don't act like the screaming of insubstantial beliefs is limited to a specific world view. There are plenty of people from the farthest reaches of the left to the farthest reaches of the right and everywhere in between who destroy chances at calm and logical conversation by acting this way. Using the "liberal" and "conservative" tags does not help...it just places people in neat unrealistic boxes as targets for unjustified hatemongering.


RE: Interesting...
By Bioniccrackmonk on 10/17/2007 8:31:36 PM , Rating: 2
Unfortunately, on this site, if you post then your votes are dismissed, so we will never know who is doing what for votes.


RE: Interesting...
By Kuroyama on 10/17/2007 10:40:05 PM , Rating: 2
Exactly. Somebody or bodies thinks TomZ is way off mark, and since voting and commenting are mutually exclusive here then they've chosen to use voting to express that. I think his remarks are relevant in this case, regardless of correctness or not, so I wouldn't do that. On the other hand, I'd mod down almost all the people responding to TomZ's latest post, because their comments contribute nothing (just as with this last sentence of mine).


RE: Interesting...
By onelittleindian on 10/17/2007 8:53:09 PM , Rating: 4
quote:
And shame on the downraters of my posts above - if you disagree, please speak up. It is pretty lame to just rate me down without even understanding the discussion
I've found that hardcore environmentalists are pretty much dead-set against free speech and open, honest debate. So don't take it too personally.


RE: Interesting...
By pliny on 10/18/2007 8:02:12 AM , Rating: 2
A core belief in AGW? TomZ, do you have any evidence for that? AGW describes to the present warming, caused by CO2 from fossil fuels. Past warmings were caused by something else, not necessarily known, although Stott's paper may help to elucidate it. I don't think anyone says they were caused by CO2, although Gore did manage to confuse this issue. CO2 was driven out of the ocean (and other reservoirs) by the warming, and so yes, lagged the warming. A passive response. Typically a rise of 3-4C produced a rise in CO2 of about 100 ppm. This may have provided positive feedback, but not much - the rise in CO2 is less than our modern fossil fuel driven increase. Water vapor feedback is much greater.

The present situation is unrelated. The extra CO2 in the air is not coming out of the oceans; it comes from our burning fossil fuels. It leads the warming.


RE: Interesting...
By porkpie on 10/18/2007 8:48:30 AM , Rating: 4
quote:
I don't think anyone says they were caused by CO2
Many scientists did believe just that. The idea was the co2 increased for whatever reason, and that made the earth warm up. Now they see the real scenario was "the earth warmed up for whatever reason and that made the co2 rise".

quote:
The extra CO2 in the air is not coming out of the oceans; it comes from our burning fossil fuels
But we don't know that. We DO know that 97% of the co2 is coming from natural sources. We ASSUME that, because co2 is rising, that the 3% we add is causing it to happen. But that assumption is looking more and more silly as time goes on.


RE: Interesting...
By pliny on 10/18/07, Rating: 0
RE: Interesting...
By masher2 (blog) on 10/18/2007 9:21:40 AM , Rating: 3
quote:
Isotopic studies establish beyond doubt that the extra CO2 in the air has a fossil fuel origin.
Sorry, but this is incorrect. Isotopic studies establish that the increase is coming from "old" CO2 (i.e. containing little to no 14C) as thus is not "recently" biologic in origin. However, this does't preclude other natural CO2 sources.

The 13C profile of atmospheric and SS CO2 has slightly declined as well. This argues against outgassing of CO2 from the ocean surface. However, it does fit nicely with the theory that atmospheric CO2 from an earlier, higher-concentration era was captured and stored by natural processes, and is now being re-released.


RE: Interesting...
By pliny on 10/18/07, Rating: -1
RE: Interesting...
By masher2 (blog) on 10/18/2007 9:37:50 AM , Rating: 5
It's even more farfetched to believe that, out of all the thousands of times a warming Earth has released vast amounts of CO2, that this time is different, and that natural rise isn't happening for some strange reason.


RE: Interesting...
By pliny on 10/18/2007 10:22:22 AM , Rating: 1
No, past releases haven't been vast - typically less than 100 ppm. Past CO2 levels (in the last 650000 years) haven't exceeded 300 ppm - we're now at nearly 390. That's different!
http://news.bbc.co.uk/2/hi/science/nature/4467420....


RE: Interesting...
By masher2 (blog) on 10/18/2007 10:31:11 AM , Rating: 5
> "past releases haven't been vast - typically less than 100 ppm. Past CO2 levels (in the last 650000 years) haven't exceeded 300 ppm "

CO2 levels have surpassed 3,000 ppm (8x current levels) many times in the Earth's history. 650,000 years is a very brief period, geologically speaking.

In any case, you're missing the point. The correlation between CO2 and temperature is very weak in the geologic record, and weakened further by research such as the focus of this article. Excluding that record, there's no reason to believe that CO2 levels of 3,000 or even 30,000 ppm will lead to catastrophic warming, due to saturation effects. It simply becomes a nonissue.


RE: Interesting...
By pliny on 10/18/2007 10:43:39 AM , Rating: 2
Well, I think you're missing the point. Correlation between past CO2 and temperature rise is not part of the argument for AGW. Only in the present circumstances is it argued that CO2, from an anthropogenic source, is forcing global warming. Past correlations may be interesting, but are not part of the argument.

650000 years covers a lot of ice age events, certainly including the one in Stott's paper.


RE: Interesting...
By onelittleindian on 10/18/2007 11:18:08 AM , Rating: 2
quote:
Past correlations may be interesting, but are not part of the argument.
Which part of the IPCC saying CO2 made a "significant contribution" to climate change did you fail to understand?

quote:
Only in the present circumstances is it argued that CO2 is forcing global warming
So this period is different than all the other thousands of times the earth has warmed up? Yeah, that's real likely.


RE: Interesting...
By grenableu on 10/18/2007 11:29:30 AM , Rating: 2
quote:
Correlation between past CO2 and temperature rise is not part of the argument for AGW.
So you're admitting Al Gore is full of crap?


RE: Interesting...
By blaster5k on 10/18/2007 9:58:11 AM , Rating: 2
That 3% (if that's what the figure is) is enough. You don't find it slightly odd that atmospheric CO2 levels went from 280 ppmv in 1800 to 315 ppmv in 1958 to 380 ppmv today? All evidence indicates that CO2 levels were fairly stable at 270-280 ppmv for a thousand years before that. Even when you look back 650,000 years, there is no evidence of a change that drastic.

That the change we're seeing right now is so sudden and coincidentally correlates well with the rates of CO2 produced by fossil fuels and land use changes should be a red flag. I suppose it's also coincidence that the balance of carbon isotopes in the atmosphere has shifted in response to fossil fuel generated emissions? Or that the CO2 level increases in Antarctic lag the northern hemisphere by a few years (since that's where most of the man made CO2 emissions are coming from)?

I think the politicizing of the issue has caused a lot of misinformation to be spread, but there is some legitimate concern. The way I see it, without our putting out the carbon emissions, we wouldn't be able to support the population we have now and not with the standard of living and life expectancy increases. A lot of the green folks don't get that part and remain insistent on ineffective solutions.

I do strongly recommend researching the issue and reading through the evidence that scientists provide for warming. It's really not based on a lot of the junk you read in the news or on one of those crazy environmentalist websites. I used to be in denial too.