CO2 levels in 2100 will hit levels last seen when the Earth was 29°F h

[WIP]

Earth’s CO2 concentration is rapidly rising to a level not seen in ∼30 to 100 million years, and Earth’s climate was extremely warm at these levels of CO2. If the world reaches such concentrations of atmospheric CO2, positive feedback processes can amplify global warming beyond current modeling estimates. The human species and global ecosystems will be placed in a climate state never before experienced in their evolutionary history and at an unprecedented rate. Note that these conclusions arise from observations from Earth’s past and not specifically from climate models. Will we, as a species, listen to these messages from the past in order to avoid repeating history?

http://climateprogress.org/2011/01/13/science-kiehl-ncar-paleoclimate-lessons-from-earths-hot-past/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+climateprogress%2FlCrX+%28Climate+Progress%29

Ever since reading Under A Green Sky two years ago by paleontologist Peter Ward, I've come to the conclusion that we can have a better grasp of future climatic change by examining past examples of when Co2 levels went up 2 to 3 times present levels and caused mass extinctions, than we can get from climate models predicting future changes. And Joe Romm's Climate Progress has a disturbing examination of recent published studies in Science, Nature, and from NASA's Goddard Institute, which includes a number of studies detailing how melting of Arctic permafrost accelerated and amplified positive feedbacks in the past, and what they can tell us about our near future:

The disinformers claim that projections of dangerous future warming from greenhouse gas emissions are based on computer models. In fact, ClimateProgress readers know that the paleoclimate data is considerably more worrisome than the models (see Hansen: ‘Long-term’ climate sensitivity of 6°C for doubled CO2). That’s mainly because the vast majority of the models largely ignore key amplifying carbon-cycle feedbacks, such as the methane emissions from melting tundra (see Are Scientists Underestimating Climate Change).

...........

The NCAR release is here: “Earth’s hot past could be prologue to future climate.” The study begins by noting:

Climate models are invaluable tools for understanding Earth’s climate system. But examination of the real world also provides insights into the role of greenhouse gases (carbon dioxide) in determining Earth’s climate. Not only can much be learned by looking at the observational evidence from Earth’s past, but such know ledge can provide context for future climate change.

...........

Indeed, in the release, Kiehl notes his study “found that carbon dioxide may have at least twice the effect on global temperatures than currently projected by computer models of global climate.”

Why is the ‘real world’ warming so much greater than the models? The vast majority of the models focus on the equilibrium climate sensitivity — typically estimated at about 3°C for double CO2 (equivalent to about ¾°C per W/m2) — only includes fast feedbacks, such as water vapor and sea ice. As Hansen has explained in deriving his 6°C ‘long-term’ sensitivity:

...........

NSF issues world a wake-up call: “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.”

Methane release from the not-so-perma-frost is the most dangerous amplifying feedback in the entire carbon cycle. The permafrost permamelt contains a staggering “1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere,” much of which would be released as methane. Methane is is 25 times as potent a heat-trapping gas as CO2 over a 100 year time horizon, but 72 times as potent over 20 years! The carbon is locked in a freezer in the part of the planet warming up the fastest (see “Tundra 4: Permafrost loss linked to Arctic sea ice loss“). Half the land-based permafrost would vanish by mid-century on our current emissions path (see “Tundra, Part 2: The point of no return” and below). No climate model currently incorporates the amplifying feedback from methane released by a defrosting tundra.

...........

In the longer term, past 2100, if we were to get anywhere near the kind of warming that Kiehl’s analysis of the paleoclimate data suggests we are headed to, that could render large tracts of the planet uninhabitable. That was the conclusion of a recent PNAS paper coauthored by Matthew Huber, professor of earth and atmospheric sciences at Purdue (release here).

http://climateprogress.org/2011/01/13/science-kiehl-ncar-paleoclimate-lessons-from-earths-hot-past/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+climateprogress%2FlCrX+%28Climate+Progress%29

[wyly]

I recall a couple of years back there was a climatologist(I wish I could recall his name) who withdrew from the debate...he was of the opinion that it was too late, that we had passed the tipping point and mass extinction was inevitable and so was the end of humanity...was he being to pessimistic or is he correct...

[TimG]

Earths CO2 concentration is rapidly rising to a level not seen in ∼30 to 100 million years, and Earths climate was extremely warm at these levels of CO2

CO2 is one many plausible explanations for the warmth. The layout of the oceans and continents was completely different and we have no data on what was happening to cloud cover. The claim that CO2 had something to do with the warmth is nothing but an unverifiable hypothesis. It is not fact.

Note that these conclusions arise from observations from Earths past and not specifically from climate models

We have next to no data on past climate. All claims of the distant past are made by first developing a paleo climate model and checking if the little bit of data we have is consistent with the climate model. If there are inconsistencies they usually are ignored if the narrative behind the model is accepted. In this case, "the CO2 is the primary driver of climate" narrative is the dominant narrative so all analyses of past climate must fit into that narrative. People who propose other narratives are ridiculed like Wegener was ridiculed for suggesting the continents drifted over time.

For example:

http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf

Edited January 14, 2011 by TimG

[Shady]

I love that they use they word "may", so when they're wrong, they can cover their asses. Anyways, who cares. Obviously technology will be much different 100 years from now. Give it a rest already alarmists.

[WIP]

I recall a couple of years back there was a climatologist(I wish I could recall his name) who withdrew from the debate...he was of the opinion that it was too late, that we had passed the tipping point and mass extinction was inevitable and so was the end of humanity...was he being to pessimistic or is he correct...

I'm thinking it was most likely James Lovelock, who is most known for the Gaia Hypothesis, which he created to explain how life has modified the planet, and how natural feedback from living organisms could balance the extreme variations that would occur without the presence of life. Unfortunately, the new age crowd took his metaphor to 'think of the Earth as a living organism' as literal truth and started worshipping a mother goddess that will protect the planet. He's over 90 years old now, and still apparently in excellent health, as he is still writing, doing interviews and public lectures. Unfortunately, he has had to spend most of the last 30 years trying to correct all of the misconceptions generated by Gaia. He did not intend it to mean that the Earth was conscious or alive, nor did he intend it to mean that Mother Nature will just fix all of the crap that we subject the environment to.

He has become darkly pessimistic about the future of the human race in recent years, because of the combined effects of overpopulation (Earth currently supports three times the number of people that can be sustained permanently), and rapidly rising greenhouse gas levels. He was the first to predict that we will reach a tipping point where stopping global warming will become impossible because of methane released in Arctic permafrost, and CO2 absorption stopping and possibly reversing in the world's oceans. And all of this goes on without any serious collective attempts to halt the march to extinction. Lovelock sees catastrophic climate change and mass population extinctions as inevitable by the end of this century, and the remaining issue will be whether we will do enough to stop complete disaster and future extinction of the human race entirely.....and I have to say, I am stuck having to agree with him on almost everything so far.

[WIP]

I love that they use they word "may", so when they're wrong, they can cover their asses. Anyways, who cares. Obviously technology will be much different 100 years from now. Give it a rest already alarmists.

Yes, lemmings never seem to be able to see when they are approaching the edge of a cliff either.

[WIP]

CO2 is one many plausible explanations for the warmth. The layout of the oceans and continents was completely different and we have no data on what was happening to cloud cover. The claim that CO2 had something to do with the warmth is nothing but an unverifiable hypothesis. It is not fact.

Yes, the relationship between CO2 and the Greenhouse Effect has been established science for over a hundred years. This is not a debateable issue any more. If you increase carbon in the atmosphere, it is going to retain more energy from the Sun.

And some past extinctions coincide with the breakup of continents. But the breakup of the supercontinent - Pangea, was also a time of high volcanic activity. The Permian-Triassic Extinction, which is the main subject of Peter Ward's research; finds that the creation of slow moving volcanic activity - the flood basalts formed in Siberia, were a time when carbon levels were extremely high, and the world's oceans suffered almost total extinction of life...except for hydrogen sulfite-producing bacteria.

Up till recent times, paleontologists were looking for asteroid hits to explain periods of mass extinction...especially after Luis Alvarez linked the K-T Extinction that killed the dinosaurs to the asteroid that hit the Yucatan 63 million years ago. But Alvarez's former grad student (Peter Ward) has noticed that volcanic activity (including at the K-T) is likely the most significant factor. Fastforwarding to the present: the reason why Ward and a few other paleontologists are stepping in to the climate debate, is because we are creating the same conditions in a much shorter period of time than previous extinctions.

We have next to no data on past climate. All claims of the distant past are made by first developing a paleo climate model and checking if the little bit of data we have is consistent with the climate model. If there are inconsistencies they usually are ignored if the narrative behind the model is accepted. In this case, "the CO2 is the primary driver of climate" narrative is the dominant narrative so all analyses of past climate must fit into that narrative. People who propose other narratives are ridiculed like Wegener was ridiculed for suggesting the continents drifted over time.

For example:

http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf

Your link is a little dated, since it seems to be made up of research that is at least ten to twenty years old. More recent developments in paleoclimate research have developed more accurate chemical tests that correlate more closely with other methods of analysis. The following study from last year, which I have posted numerous times previously, can accurately plot CO2 levels back 20 million years, and as the headline notes, we have to go back 15 million years to a time when atmospheric CO2 levels were this high. Chemical analysis of rocks may not be as accurate as ice core samples, but it's getting better:

Last Time Carbon Dioxide Levels Were This High: 15 Million Years Ago, Scientists Report

[TimG]

Yes, the relationship between CO2 and the Greenhouse Effect has been established science for over a hundred years.

The relationship exists but we have no reliable way to quantify the magnitude of the effect. The current narrative presumes that nothing other than CO2 matters. It is likely wrong. CO2 is one of many factors and a climate may haveen been warm for reasons unrelated to CO2.

Fastforwarding to the present: the reason why Ward and a few other paleontologists are stepping in to the climate debate, is because...

Don't be naive. Ward is jumping on the CO2 band wagon because it gets him funding. Scientists need to eat too. He could be right but lets not pretend his motives are altruistic.

YesMore recent developments in paleoclimate research have developed more accurate chemical tests that correlate more closely with other methods of analysis.

Who cares about CO2? The problem is we don't know what the *temperature* was 100 million years ago nor do we have data on the average cloud cover. We can guess that it was warmer than today but we don't have a numerical value. To get around this paleo researchers ASSUME that CO2 is the only thing that affects temps and they estimate the temps from the CO2 levels. This means that none of these recent paleo claims provide evidence supporting the CO2-climate link because that link is the starting assumption. Edited January 14, 2011 by TimG

[TimG]

Yes, lemmings never seem to be able to see when they are approaching the edge of a cliff either.

I find it extremely ironic that you use an analogy based on a fiction created by Disney:

http://www.snopes.com/disney/films/lemmings.asp

Lemming suicide is fiction. Contrary to popular belief, lemmings do not periodically hurl themselves off of cliffs and into the sea. Cyclical explosions in population do occasionally induce lemmings to attempt to migrate to areas of lesser population density.

Lesson: believing something does not make it is true.

Edited January 14, 2011 by TimG

[Guest TrueMetis]

The relationship exists but we have no reliable way to quantify the magnitude of the effect. The current narrative presumes that nothing other than CO2 matters. It is likely wrong. CO2 is one of many factors and a climate may haveen been warm for reasons unrelated to CO2.

I'm going to say this again that CO2 warms and how much it warms by can be determined by basic physics, and of course there are other factors climate scientists know these factors quite well because they discovered them.

[TimG]

I'm going to say this again that CO2 warms and how much it warms by can be determined by basic physics

A complete myth. They can calculate the change in radiative forcing but going from radiative forcing to a specific temparature change is a non-trivial problem which has not been solved mathematically. All of the science is based on an estimate the relationship and those estimates are far from perfect.

Here is a discussion of the problems with the current methods:

http://judithcurry.com/2010/12/14/co2-no-feedback-sensitivity-part-ii/

of course there are other factors climate scientists know these factors quite well because they discovered them.

And ignored them. Clouds are a good example. A 10% change in cloud cover can cause significant warming or cooling yet paleoclimate scientists always assume that average cloud cover was the same as today even thought they have no reasonable basis to make that assumption. If there were fewer clouds 100 million years ago because of changes in vegetation, land distribution, cosmic rays or whatever then that would explain the warmth without CO2.

Bottom line: science is only as reliable as its assumptions. In the case of paleoclimate there are so many assumptions it not reasonable to put much weight on their conclusions. They might be true. Might not. We can't know and neither do the scientists working in the field.

[Shady]

Yes, lemmings never seem to be able to see when they are approaching the edge of a cliff either.

Your alarmism is amusing. Do you actually think we'll be using combustion engines, etc in the year 2100?

[Bonam]

He has become darkly pessimistic about the future of the human race in recent years, because of the combined effects of overpopulation (Earth currently supports three times the number of people that can be sustained permanently)

Sorry but what the heck does that mean and how was that calculated? Who said the Earth can permanently support exactly 2.3 billion people? Permanently support at what level of comfort and at what level of technology? These kinds of predictions are utterly meaningless. The Earth's carrying capacity for human civilization is determined almost entirely by the technology of that civilization rather than by anything else, as can be clearly seen by the strong correlation between technological progress and the Earth's human population.

You make that statement with such confidence but it is utterly arbitrary.

[waldo]

CO2 is one many plausible explanations for the warmth. The layout of the oceans and continents was completely different and we have no data on what was happening to cloud cover. The claim that CO2 had something to do with the warmth is nothing but an unverifiable hypothesis. It is not fact.

CO2 most certainly was a factor in paleo-climate temperature... as was, for example, solar luminosity and paleogeography - a recent MLW thread spoke directly to this in relation to discussion of CO2-temperature correlation within a paleo-climate. You won't find, as I'm aware, any position that presumes on CO2, to the exclusivity of all other natural influences... whether that's for considerations of paleo-climate or 'modern-day climate'.

We have next to no data on past climate. All claims of the distant past are made by first developing a paleo climate model and checking if the little bit of data we have is consistent with the climate model. If there are inconsistencies they usually are ignored if the narrative behind the model is accepted. In this case, "the CO2 is the primary driver of climate" narrative is the dominant narrative so all analyses of past climate must fit into that narrative. People who propose other narratives are ridiculed like Wegener was ridiculed for suggesting the continents drifted over time.

For example:

http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf

again, perhaps you should actually have a look at analysis of related paleo-climate studies... CO2 is most certainly a primary driver of modern-day climate (as well as a feedback). Perhaps you could elaborate on how this modern-day, as you call it, "narrative", presumes to impart, as you state, "ridicule" upon alternative 'narratives', particularly within your highlighted paleo-climate periods. Where's the so-called ridicule you speak to in relation to your posted study/paper link... it's a paper that went through the rigour of peer-response and simply didn't hold up to scientific scrutiny - cosmic ray flux is heavily studied and published upon... of course it is. Your linked Shaviv/Veizer paper was heavily manipulated and hyped to offer a conclusion for lower current climate sensitivity based upon a correlation between cosmic ray flux and temperature over hundreds of millions of years... notwithstanding the conflicting statement within the paper itself; specifically, "As a final qualification, we emphasize that our conclusion about the dominance of the CRF over climate variability is valid only on multimillion year time scales. At shorter time scales, other climatic factors may play an important role..."

one of several responses to your linked Shaviv/Veizer paper: - Rahmstorf et al - AGU Eos,Vol. 85, No. 4, 27 January 2004... standard operating procedure... scientists responding to published science... this is your stated ridicule???

Conclusion

Two main conclusions result from our analysis of Shaviv and Veizer [2003].The first is that the correlation of CRF and climate over the past 520 m.y.appears to not hold up under scrutiny. Even if we accept the questionable assumption that meteorite clusters give information on CRF variations,we find that the evidence for a link between CRF and climate amounts to little more than a similarity in the average periods of the CRF variations and a heavily smoothed temperature reconstruction. Phase agreement is poor. The authors applied several adjustments to the data to artificially enhance the correlation.We thus find that the existence of a correlation has not been convincingly demonstrated.

Our second conclusion is independent of the first. Whether there is a link of CRF and temperature or not, the authors’ estimate of the effect of a CO2 doubling on climate is highly questionable. It is based on a simple and incomplete regression analysis that implicitly assumes that climate variations on time scales of millions of years, for different configurations of continents and ocean currents, for much higher CO2 levels than at present, and with unaccounted causes and contributing factors, can give direct quantitative information about the effect of rapid CO2 doubling from pre-industrial climate.The complexity and non-linearity of the climate system does not allow such a simple statistical derivation of climate sensitivity without a physical understanding of the key processes and feedbacks. We thus conclude that Shaviv and Veizer [2003] provide no cause for revising current estimates of climate sensitivity to CO2.

in any case... I find it quite interesting to read this abstract from a 2007 paper co-authored by the same Veizer - (Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era) that co-authored your linked Shaviv/Veizer (2003) paper; specifically to this concluding statement:

Our results are consistent with the proposal that increased atmospheric carbon dioxide concentrations drive or amplify increased global temperatures

Huh! Say what... hey TimG, what happened in those intervening 4 years? Did Veizer 'get religion'?... was he 'reborn'?

[waldo]

For example:

http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf

I love that they use they word "may", so when they're wrong, they can cover their asses.

hey Professor! How was the box? Are ya any..... cooler?

oh, wait... that's the 'skeptical' paper TimG linked to - you weren't referencing that paper... were you? Given all those uses of "may" within that paper, your vaunted ShadyAnalysis seems to have misfired. At least your hiatus hasn't interrupted and/or interfered with your consistency level!

[TimG]

You won't find, as I'm aware, any position that presumes on CO2, to the exclusivity of all other natural influences

Yes. CAGW Scientists are quite dishonest when it comes to such things. If they are left to their own devices teh will talk of nothing except CO2 but as soon as they are confronted with the rediculousness of the that position they stare at their shoes while the acknowledge other factors. IOW, some caveat in the fine print does not make up for their single minded obsession with one factor.

Your linked Shaviv/Veizer paper was heavily manipulated and hyped to offer a conclusion for lower current climate sensitivity based upon a correlation between cosmic ray flux and temperature over hundreds of millions of years.

That is the opinion of the CO2 mafia which does not mean much. It Shaviv has answered his critics. The paper is a reasonable hypothesis that cannot be rufuted with any data available today. There have been many other examples of scientists who were told their hypothesis were refuted only to be vindicated decades later. Only a buffoon completely rejects a plausible physical hypothesis simply because the data we have today is sparse and contradictory.

is valid only on multimillion year time scales. At shorter time scales, other climatic factors may play an important role

You are nothing but a alarmist talking point bot. Did you happen to notice this thread was talking about climate over multimillion years scales? I am guessing you just saw the words 'comic rays' which triggered the 'cosmic rays CAGW spam' subroutine. Edited January 15, 2011 by TimG

[waldo]

Here is a discussion of the problems with the current methods:

whaaa! Such a surprise you'd champion the bag-lady, dotty aunt of climate science... she exhausted any credibility she had a few short weeks into her sham/scam. I was particularly impressed with her opening comment that she put a whole day into thinking about her post ... blog science rules! Why should scientists bother spending decades/careers on specialized and targeted research/study - JC nailed it in a day! Let's see her push that blogfest up into a published paper (/snarc).

[WIP]

The relationship exists but we have no reliable way to quantify the magnitude of the effect. The current narrative presumes that nothing other than CO2 matters. It is likely wrong. CO2 is one of many factors and a climate may haveen been warm for reasons unrelated to CO2.

Since there is a lengthy rebuttal of your objections to CO2 being a crucial factor in climate change in post#14, there's not much point to repeating ad nauseum.

Don't be naive. Ward is jumping on the CO2 band wagon because it gets him funding. Scientists need to eat too. He could be right but lets not pretend his motives are altruistic.

You never heard of him before, but you already know his motivations. I've been following his writing since he collaborated with Donald Brownlee on Rare Earth, which attempts to throw a little cold water on the common belief found in Star Trek and the thoughts of Carl Sagan and many others, that the Universe is teeming with advanced extraterrestrial civilizations. Ward and Brownlee took a hard look at limited range of habitable zones in our galaxy, and concluded that planets supporting complex life forms would be extremely rare.

Later, from some of his public lectures, I learned that Ward put his scientific career in jeopardy while working for Luis Alvarez in the Canary Islands, at a rock strata from the time of the P-T Extinction. He was supposed to be looking for evidence of large asteroid impact, which Alvarez became convinced was the cause of all mass extinctions. Instead, Ward started moving in the direction of natural earth changes - mainly volcanic activity - causing "The Great Dying" at the end of the Permian. He ended up with his research funding cut by the Alvarez team, and having to look for new employment and finding some other ways to raise funds and continue his own research. So, to me that sounds like someone who is dedicated to his work and in search of the truth, not easy money!

[WIP]

Your alarmism is amusing. Do you actually think we'll be using combustion engines, etc in the year 2100?

Maybe not; but those jetpacks and flying cars may add to greenhouse gas levels.

[waldo]

Yes. CAGW Scientists are quite dishonest when it comes to such things. If they are left to their own devices teh will talk of nothing except CO2 but as soon as they are confronted with the rediculousness of the that position they stare at their shoes while the acknowledge other factors. IOW, some caveat in the fine print does not make up for their single minded obsession with one factor.

just who are your "CAGW Scientists"... oh... you mean working climatologists? Your cartoonish assessment doesn't stand up to published science or public statements. Again, whether paleo-climate or 'modern-day' climate, all influences are considered not to the exclusion of any influences. As always, don't hesitate to step forward and make your case for an alternative to CO2 for the relatively current accelerated warming. It seems you have a hankering for cosmic rays - hey? Have at er...

That is the opinion of the CO2 mafia which does not mean much. It Shaviv has answered his critics. The paper is a reasonable hypothesis that cannot be rufuted with any data available today. There have been many other examples of scientists who were told their hypothesis were refuted only to be vindicated decades later. Only a buffoon completely rejects a plausible physical hypothesis simply because the data we have today is sparse and contradictory.

"CO2 mafia"??? I realize you and your denier brethern have an ever growing frustration with an inability to present an alternative to CO2... but really, "mafia"? Really? Shaviv hasn't answered his critics... certainly not based on your linked 2003 paper... certainly not on his followup 2005 paper. I referenced one example of a clear and precise refutation to your linked 2003 Shaviv/Veizer paper - Rahmstorf et al - AGU Eos,Vol. 85, No. 4, 27 January 2004. Hey now... I note you've dropped reference to Veizer - why so? How is it that when you presume to make your TimG case 'for whatever'... you never qualify it with presumed sparse and contradictory data... you know, like you regularly trot out when you presume to chastise and/or denigrate today's consensus science.

You are nothing but a alarmist talking point bot. Did you happen to notice this thread was talking about climate over multimillion years scales? I am guessing you just saw the words 'comic rays' which triggered the 'cosmic rays CAGW spam' subroutine.

bloody hell! You linked to a paper with a position that presumes on galactic cosmic rays... where one of it's co-author's, Shaviv, publicly made inferences to present day sensitivity levels... where the denialsphere hyped the paper to the nth degree in terms of presenting a basis for reduced current sensitivity. And you're calling me out for addressing the paper in terms of both paleo-climate and 'modern-day' climate aspects?

Edited January 15, 2011 by waldo

[WIP]

Sorry but what the heck does that mean and how was that calculated? Who said the Earth can permanently support exactly 2.3 billion people? Permanently support at what level of comfort and at what level of technology? These kinds of predictions are utterly meaningless. The Earth's carrying capacity for human civilization is determined almost entirely by the technology of that civilization rather than by anything else, as can be clearly seen by the strong correlation between technological progress and the Earth's human population.

You make that statement with such confidence but it is utterly arbitrary.

I'm not sure if James Lovelock is still actively doing scientific research, but the numbers that are gathered to estimate human ecological footprint (basically, what we are taking from our natural environment) has come from a number of sources; and although the numbers fluctuate...think of China's impact for example, which has substantially increased over the last 25 years with their rapid industrialization program -- the world population (which will reach 7 billion this year) is consuming about 25% more resources than Earth is producing – during any given time period. And that means we are consuming our resource base. Obviously this 25% overshoot is not sustainable:

We maintain this overshoot by liquidating the Earth’s resources. Overshoot is a vastly underestimated threat to human well-being and the health of the planet, and one that is not adequately addressed.

Today humanity uses the equivalent of 1.5 planets to provide the resources we use and absorb our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year.

Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s, we will need the equivalent of two Earths to support us. And of course, we only have one.

http://www.footprintnetwork.org/en/index.php/GFN/page/footprint_basics_overview/

Another crucial point to understand is this: the longer we overshoot and consume more resources than the sustainable level, the more the long-term “sustainable level” actually declines! So, the longer we are taking out more than is being put back, the less the level of sustainable consumption of resources, and we may end up four, five or six times the sustainable level.

Edited January 15, 2011 by WIP

[Bonam]

I'm not sure if James Lovelock is still actively doing scientific research, but the numbers that are gathered to estimate human ecological footprint (basically, what we are taking from our natural environment) has come from a number of sources; and although the numbers fluctuate...think of China's impact for example, which has substantially increased over the last 25 years with their rapid industrialization program -- the world population (which will reach 7 billion this year) is consuming about 25% more resources than Earth is producing – during any given time period. And that means we are consuming our resource base. Obviously this 25% overshoot is not sustainable:

We maintain this overshoot by liquidating the Earth’s resources. Overshoot is a vastly underestimated threat to human well-being and the health of the planet, and one that is not adequately addressed.

Today humanity uses the equivalent of 1.5 planets to provide the resources we use and absorb our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year.

Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s, we will need the equivalent of two Earths to support us. And of course, we only have one.

http://www.footprintnetwork.org/en/index.php/GFN/page/footprint_basics_overview/

Another crucial point to understand is this: the longer we overshoot and consume more resources than the sustainable level, the more the long-term “sustainable level” actually declines! So, the longer we are taking out more than is being put back, the less the level of sustainable consumption of resources, and we may end up four, five or six times the sustainable level.

All of which is in dire contradiction with your prior claim of us presently being three times over the Earth's capacity. Again, that speaks to the deep inherent ambiguity of any such estimates. And, again, any such estimate depends far more on our level of technological advancement than it does on the Earth itself. How does a simple technological advance, like, for example, an all-electric car, or a fusion power plant, or a genetically modified crop, or a wood material substitute, etc, affect that estimate? Such advances are constantly being made, allowing us to support an ever growing number of humans on Earth. The only real fundamental limitation is the availability of energy, and we have not even begun to tap even a tiny fraction of the energy available.

[Shady]

Another crucial point to understand is this: the longer we overshoot and consume more resources than the sustainable level

Complete nonsense. Just more sterilization/one-child policy/totalitarianism disguised as climate alarmism.

[waldo]

That is the opinion of the CO2 mafia which does not mean much. It Shaviv has answered his critics. The paper is a reasonable hypothesis that cannot be rufuted with any data available today. There have been many other examples of scientists who were told their hypothesis were refuted only to be vindicated decades later. Only a buffoon completely rejects a plausible physical hypothesis simply because the data we have today is sparse and contradictory.

"CO2 mafia"??? I realize you and your denier brethern have an ever growing frustration with an inability to present an alternative to CO2... but really, "mafia"? Really? Shaviv hasn't answered his critics... certainly not based on your linked 2003 paper... certainly not on his followup 2005 paper. I referenced one example of a clear and precise refutation to your linked 2003 Shaviv/Veizer paper - Rahmstorf et al - AGU Eos,Vol. 85, No. 4, 27 January 2004. Hey now... I note you've dropped reference to Veizer - why so? How is it that when you presume to make your TimG case 'for whatever'... you never qualify it with presumed sparse and contradictory data... you know, like you regularly trot out when you presume to chastise and/or denigrate today's consensus science.

would you like... more? I referenced this paper in a prior MLW thread relative to paleo-climate CO2-to-temperature correlation - CO2 as a primary driver of Phanerozoic climate - Royer et at (2004) - Geological Society of America...

Royer et al (also) corrected your linked Shaviv/Veizer paper's δ18O record for the effect of changing pH (re: values of calcitic shells over the Phanerozoic)... effectively presenting a corrected climate record that no longer followed the Shaviv/Veizer 'cosmic ray model' but, rather, correlated well with the Geocarb III CO2 reconstruction.

your blinding group-think prevents you from acknowledging that your favoured 'anything but CO2' alternatives have been... and continue to be... properly addressed within the science - per norm... per standard operating procedure... per peer-review/peer response. You just have difficulty with the outcome - hey?

[TimG]

Since there is a lengthy rebuttal of your objections to CO2 being a crucial factor in climate change in post#14, there's not much point to repeating ad nauseum.

A rebuttal? Hardly. Waldos response can be summarized as:

1) A blantently false assertion that 'other factors' are considered when he knows perfectly well that other factors are ignored or minimized in the recent literature. CO2 is treated as the master 'control knob' for paleoclimate (those are the exact words used by scientists).

2) An irrelevant spew on the effect of cosmic rays on current climate when we were talking about paleo climate.

Shaviv has answered is critics but Waldo - in a true CAGW fashion - stops reading one he finds some talking points he can repeat ad nausium. For the record: here is a summary of Shavivs response:

5. The work of Shaviv & Veizer (2003) was proven wrong. The work of Shaviv & Veizer attracted two published criticisms (Royer et al. 2004 and Rahmstorf et al. 2004). The first was a real scientific critic, where it was argued that the 18O/16O based temperature reconstructions (of Veizer et al. 2000) has an unaccounted systematic error, due to ocean pH, and hence the atmospheric pCO2 level. Shaviv (2005) considered this effect and showed that instead of an upper limit to the effect of CO2 doubling, of 1°C, Earth's sensitivity increases to 1-1.5°C, but the basic conclusion that CRF appears to be the dominant climate driver remains valid (as later independently confirmed by Wallman 2004). Rahmstorf et al. 2004 published a comment stating that almost all Veizer and I did was wrong. We showed in our response why every comment is irrelevant or invalid. In their response to the rebuttal, Rahmstorf et al. did not address any of our rebuttal comments (I presume because they could not). Instead, they used faulty statistics to demonstrate that our results are statistically insignificant. (Basically, they used Bartlett's formula for the effective number of degrees of freedom in a limit where the original derivation breaks down).

http://www.sciencebits.com/RealClimateSlurs

3) An pathetic ad hom attack on a climate scientist who is willing publically discuss the gaps and problems with the numerical theory behind the CO2 - temperature link.

When it comes to science I see no difference between CAGW proponents and Intelligent Design proponents. Both groups of people have decided that they already know the answer they want and ignore all ideas that go against it.

Edited January 15, 2011 by TimG