Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Is it safe to double atmospheric Carbon Dioxide over a 200 year period?

Posted on 24 December 2010 by fingerprinter

We are on track to double pre-industrial atmospheric carbon dioxide concentrations. In assessing the risk, the above question is much more fundamental than asking how much the climate warmed over the 20th century. So what’s the answer?

Society has standard approaches for assessing risk and safety. When it comes to assessing risk for major intervention, this approach entails a null hypothesis, or base assumption, that things are unsafe until proven safe.  Examples occur in medicine, engineering and just about every human activity. In medicine, a drug company can not assume that a new vaccine is safe, with the burden of proof on others to prove it is unsafe. Note that this is different to determining whether the vaccine is effective, where the null hypothesis could be that there is no association between the vaccine and immunity. Rather, the null hypothesis for the risk assessment relates to the question, can I use this vaccine for a major public vaccination program?

When it comes to carbon pollution, the normal convention for risk assessment goes right out the window. The scientific null hypothesis that there is no association between carbon dioxide and climate change is easily broken. But the public risk question really relates to doubling the atmospheric carbon dioxide concentration in 200 years. In other words, is altering atmospheric chemistry in that manner safe?  In the weird world of greenhouse policy, we would like everyone to assume that putting 3.6 billion tons of carbon into the atmosphere is entirely safe, with the onus on climatologists to prove otherwise.

Taking the wrong null hypothesis has serious implications for the way the science is assessed. Going back to our medical analogy, even a relatively small amount of evidence that the vaccine is unsafe is enough to inform a risk assessment. In other words, the null hypothesis stands. You need to produce a great deal of evidence to satisfy authorities that the vaccine is safe.

In the assessment of carbon pollution, we have this the wrong way around. Small uncertainties in the conventional science are used to reinforce the notion that doubling atmospheric carbon dioxide is entirely safe. Most importantly, and somewhat amazingly when you stop to think about it, major polluters and proponents of continued carbon pollution have never proved that their product is safe. Not only that, they haven’t even been asked, by governments and the public alike, to prove that their product is safe.

This means that, to date, we have no studies demonstrating that the climate system is insensitive to such increases in carbon dioxide, and a mountain of evidence indicating that doubling atmospheric carbon dioxide will result in dramatic climate change. Yet still, we refuse to really accept the risks. One of the biggest reasons for this is that the skeptics have been successful in limiting public discussion to 20th century global mean temperature. In reality, the case against doubling atmospheric carbon dioxide is well established before we look at the 20th century climate record.

One of the most certain things in climate science is that increasing carbon dioxide warms the climate system. Doubling atmospheric concentrations is sure to cause significant warming of the climate system. And doubling a over a 200 year period represents one of the most rapid changes in atmospheric carbon dioxide in the history of the Earth.

The certainty that carbon dioxide warms the climate system does not rely on any 20th century climate observations, such as employed in fingerprinting studies. These studies seek to determine how much the 40% increase in carbon dioxide over the 20th century has already affected the climate. Rather, the evidence against increasing carbon dioxide is much more fundamental.

The first place to look is of course the paleoclimate record. Over the last several decades of research, the sensitivity of the climate system to changes in carbon dioxide has been established through ice core samples and other proxy climate indicators. In short, past climates with high atmospheric carbon dioxide concentrations were very warm, unless incoming solar radiation was low. Rapid changes in carbon dioxide (such as due to planetary volcanic activity or asteroid strikes) resulted in rapid changes in the climate system. The literature on this topic remains unchallenged; in the Earth’s geological history, if carbon dioxide concentrations increased, the planet warmed.

The second and more important place to look is the fundamental physics and chemistry- using mathematical modelling. Models used in climate come in different shapes and sizes. Some of the most basic models, such as the behaviour of gases exposed to radiation of different wavelengths, are well established physical models.

Far from being controversial, numerical models are used in all modern fields of science. Mathematical models are implicit in our understanding of the universe. For example, the governing equation for the gravitational effect is also 'just a model'.  In fact, it’s the very definition of a model, since we do not actually understand how gravity works. However our mathematical model of the nature of gravity has been verified through countless observations. We are quite certain that our mathematical model of gravity accurately describes the Newtonian universe. These principles are not negotiable like the tenets of social sciences or economics. They are fundamental laws. The universe doesn't fudge fundamental laws of scale.

Similarly, the mathematical model of the organisation of an atom; neutrons, protons, electrons, is just a model. We cannot actually look inside an atom. But the model has been verified and it holds as a fundamental certainty.

The mathematical model of how atoms absorb and re-emit radiation in discrete energy packets and in discrete wavelengths is also a model. It also faithfully describes the universe. A whole heap of technology is built on the certainty of this model. If these models did not work, then most of the appliances in your house would also not work, including the microwave oven and the television.

Therefore we can faithfully model how radiation passing through layers of radiative gas will be absorbed and re-emitted. There is nothing speculative about this either. This is fundamental physics and chemistry, text book material rather than brand new science.


(Image created by Robert A. Rohde / Global Warming Art)

If anyone seriously thinks that our understanding of radiation is wrong, then could they please publish that alternative theory in a proper scientific journal so we can all absorb a new reality? You will need to overturn more than 100 years of physics in the process. You will also likely win a Nobel Prize for your efforts. The incentive is there.

You see, you can't just say you don't agree with the fundamental laws of physics, or that you are not convinced by them, and leave it at that. At least, not if you want to be taken seriously in the scientific community (as opposed to simply confusing the public with red herrings). As an aside, I suspect that being taken seriously by the science community has never been a key priority for the skeptics.  By publishing almost exclusively on blogs and in the opinion sections of newspapers, and eschewing peer-reviewed scientific journals, they have staked out their real audience. Contributing to science has nothing to do with it.

Now where were we? Oh yes, we understand entirely how radiative gases like carbon dioxide absorb and re-emit radiation from physics, quantum physics and chemistry. We also understand the physics of radiation (for example the Stephan Boltzmann relationship). We understand entirely that if you increase the concentrations of carbon dioxide in the atmosphere, you will warm the surface of the planet. This result is repeatable (you get the same answer) using a simple model of radiation physics alone (just a couple of lines of code) or using a fully coupled atmosphere-ocean-sea-ice model with turbulent mixing. People have been trying to break this result for fifty years and have not. That’s how science works.

The sensitivity of the atmosphere to greenhouse gases can also be observed on nearby planets (Mars and Venus) and is consistent with the maths. The maths is also supported by the observed feedback mechanism between temperature and carbon dioxide in the ice-core record and other paleo indicators. If you double or even triple atmospheric carbon dioxide, which we will do sometime this century or early next, you will significantly warm the climate system. This is well above a 95% probability, and is hence a near certainty. No one has disproved any of this in the literature. No drug would make it onto the market with that kind of evidence running against it.

The climate system is complex, so the fundamental physics operates over many interacting variables. As such, many things can act to slow down the rate of warming or amplify it, such as the warming-water vapour feedback mechanism. But the system is not that complex, and is certainly far less complex than the human body. And the complexity of the system cannot change the radiative properties of carbon dioxide. Hence, over time, and given the rate of carbon dioxide increases that are proposed, warming will be set in train and is assured from the fundamental physics. Hence we are certain from all the science that the mean trajectory we are now on is a warming trajectory. Small uncertainties in the rate of future warming are irrelevant to the risk assessment. That’s like pinning the risk assessment associated with childhood exposure to UV radiation to uncertainty in the exact age that skin cancer is most likely to occur.

The climate of the deep past has shown that we are nowhere near the natural limits of warming for planet Earth. In other words, the current state of the climate has more things that can amplify warming than it does things that will keep a lid on the warming. There are mechanisms that limit warming, but we have plenty of room to warm given that the level of pre-industrial carbon dioxide was very low in relation to extremely warm climates in the distant past. This level of warming is more than enough to elevate sea level and change the predominant patterns of global climate. The uncertainties in the context of the enhanced greenhouse effect are actually more worrying than they are reassuring. This is a concept that the public does not understand very well.

Guess what? I haven’t even talked about a 20th century thermometer reading, and we already have heaps of evidence against the safety of rapidly doubling atmospheric carbon dioxide. The matching greenhouse fingerprints in the 20th century climate record are really the final nail of evidence.  If there is some study that contradicts the fundamental science, then where is it? No one has managed to find an alternative solution after decades of trying. While the skeptics will throw up the occasional vaguely set-out paper from fringe (and mostly non peer-reviewed) journals, they can not produce a set of key papers which demonstrate that doubling atmospheric chemistry has no significant effect on the climate system. And that is what they wish to prove is it not? It is certainly what they should be required to do.

So people should ask the skeptics their own set of questions. Why have they never produced a repeatable formulation of the physics as they see it? Why have they never developed their own climate models, and performed their own model experiments? Why have they never produced their own paleoclimate reconstructions? Why have they never compiled their own record of surface temperature?  Apparently, the lack of published research showing the inert nature of atmospheric carbon dioxide changes is the result of a long running, worldwide scientific conspiracy.

But that too doesn't stand up. With all the money supposedly at stake, the complete lack of credible research by the skeptics points to a complete inability to successfully argue their case in scientific circles. If destroying the conventional science was as easy as they suggest, the major polluters would have funded such research twenty years ago, and moved on. Again, the incentive is there, and large companies are more than capable of funding and producing credible research. But, importantly, they have not attempted to do so.

0 0

Printable Version  |  Link to this page

Comments

Prev  1  2  3  Next

Comments 51 to 100 out of 109:

  1. it sounds very much like the cheapest and most reliable nightmare.
    0 0
  2. #46: "The plants are going to love it but nobody listens the them ... " Nice of gc to entertain with his Lorax imitation. Unfortunately, messing with Mother Nature can produce surprising results: The direct, physiological response of plants to elevated CO2 generally acts to weaken the earth’s hydrologic cycle by lowering transpiration rates across the globe. Lowering transpiration alone would tend to enhance soil moisture. However, reduced recirculation of water in the atmosphere, which lowers precipitation, leads to more arid conditions overall (simulated global soil moisture decreases by 1%), particularly in the Tropics and midlatitudes. And if altering the hydrologic cycle isn't a big enough gamble, here's evidence for another unintended consequence: Elevated levels of atmospheric carbon dioxide (CO2), a consequence of anthropogenic global change, can profoundly affect the interactions between crop plants and insect pests and may promote yet another form of global change: the rapid establishment of invasive species. So that could add famine, locusts and probable cattle diseases to our list. Just how many Biblical-style plagues do the deniers consider 'safe'?
    0 0
  3. archiesteel (#48), According to the FACE experiment (Nicolas School of the Environment), CO2 does make plants grow more. When CO2 concentrations are increased, plants grow faster until scarcity of some other nutrient intervenes. You don't need university researchers to tell you this kind of thing. Enhancing the CO2 in greenhouses has been a common practice for decades. If you are right, global temperatures will rise as a result of doubling the CO2 concentration in the atmosphere. However, you are in error to link desertification to increased temperatures. It is falling temperatures that increase desertification, while rising temperatures cause increased precipitation.
    0 0
  4. Re: gallopingcamel You need to read Dai et al 2010, then. Hope your Christmas was merry, The Yooper
    0 0
  5. It's also worth mentioning that commercial greenhouses using CO2 enriching maintain between 800 to 1200 ppm CO2 content. If we have to get there to see any "benefit" we'll end up with quite an interesting geo-engineering experience, especially if it's done in just another few decades.
    0 0
  6. #53: "Enhancing the CO2 in greenhouses has been a common practice" And we are comparing the artificial, closed environment of commercial greenhouses to the open atmosphere because ...? Does it occur to you that moisture content in a commercial greenhouse is also controllable? "in error to link desertification to increased temperatures." Or not: "more arid conditions" "Increased drought frequency will likely cause major changes in vegetation cover." "An Australian study offers further confirmation of the climate change phenomenon – arid regions are indeed becoming drier and higher rainfall regions wetter" Interestingly, there seems to be reports of both extreme drought and floods. Are we up to 7 out of 10 yet?
    0 0
  7. @gallopingcamel: as others have pointed out, it's not just as simple as doubling CO2. In a greenhouse you control temperature, moisture and the amount of nutrients the plants get. You are the perfect example of the old saying, "a little knowledge is dangerous." I suggest you learn more about growing plants (I myself have spent a lot of time working in a greenhouse at my sister's farm) before pushing the myth that "increased atmospheric CO2 will have a beneficial effect on plant growth" when there is *no* indication this would be the case.
    0 0
    Moderator Response: As GP perfectly well knows, there are other threads that are appropriate for his repetition of these arguments. Deletions will commence soon.
  8. It’s probably futile to draw your attention yet again to the science that informs our understanding on these issues gallopingcamel, but in the seasonal spirit let’s have another go.
    gallopingcamel:”You don't need university researchers to tell you this kind of thing. Enhancing the CO2 in greenhouses has been a common practice for decades.”
    Sadly, that only works under conditions of optimal water and fertilization supplementation. In the real world that’s not how the vast majority of food crops are grown. If you were to properly assess the FACE experiments that aim to characterize the effects of CO2 supplementation under field conditions, the picture isn’t so rosy: S. P. Long, et al (2006) Food for Thought: Lower-Than-Expected Crop Yield Stimulation with Rising CO2 Concentrations Science 312, 1918-1921 abstract A. D. B. Leakey et al. (2009) Elevated CO2 effects on plant carbon, nitrogen, and water relations: six important lessons from FACE J. Exp. Botany 60, 2859-2876
    “More broadly, the stimulation of seed yield in response to growth in elevated [CO2] is ~50% lower in FACE experiments than in enclosure studies for the world’s four most important crops (Long et al., 2006; Ainsworth, 2008; Ainsworth et al., 2008a). With the caveat that FACE experiments have been limited in number and geographical coverage, the much lower elevated [CO2] fertilization factor on yield observed under agronomicaly relevant conditions has potentially serious implications for projections of world food supply……………. Most important though will be understanding why our major food crops fail to achieve the improved production under elevated [CO2] that can be achieved in protected environments and by some non-crop species.”
    J.A. Langley & J. P. Megonigal (2010) Ecosystem response to elevated CO2 levels limited by nitrogen-induced plant species shift Nature 466, 96–99 abstract This reiterates that any [CO2] effect requires enhanced N (nitrogen) nutrient as is well known, but the combined effects of [CO2]/N are likely to be counterproductive with respect to plant growth in natural ecosystems due to CO2/N-induced shifts in plant species. So natural ecosystems may respond poorly to enhanced [CO2] due to water and nutrient limitation and species shifts. In other words the terrestrial ecosystem is likely increasingly to falter as a sink to "mop up" large amounts of enhanced anthropogenic [CO2]. Managed agricultural production may cope with enhanced [CO2] but is likely to become more expensive to support due to nutrient and water limitations, as indicated by FACE studies (e.g. as in the first two papers above).
    gallopingcamel: ” However, you are in error to link desertification to increased temperatures. It is falling temperatures that increase desertification, while rising temperatures cause increased precipitation”
    Wrong. The predictions on changing precipitation patterns in a warming world are borne out by real world observations. The latitude band from around the equator to near 30 oN has become drier as the Earth has warmed during the 20th century, much as predicted, and will continue to do so. This latitudinal band of reduced precipitation will widen as the Earth continues to warm (and so Amazonia, for example, is expected to dry progressively towards the South as the Earth warms). The higher latitudes (especially above 50o N and below 10 o) have seen enhanced precipitation. Global warming and shifts in precipitation regimes is expected (and already observed) to lead to amplification of extreme precipitation events (one could cite more papers on this, but Allen et al. 2008 is a decent starting point). In other words those parts of the world that are water-limited are becoming more susceptible to drought as global warming proceeds…those areas of the world that don’t need more rain (higher latitudes) are getting more: X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 abstract RP Allen et al. (2008) Atmospheric warming and the amplification of precipitation extreme Science 321, 1481-1484 abstract
    0 0
    Moderator Response: Since there already is a history of comments on this topic on the thread CO2 Is Not a Pollutant, how about everybody respond over there.
  9. this article actually doesn't address what it claims to address. in the argument 'is it safe', this article merely addresses whether or not increased CO2 causes warming - not whether that warming is safe or unsafe. i am a skeptic. the holes in the alarmism arguments are large enough to drive a CO2 belching truck through. there has been no verified, demonstrable evidence yet presented that there have been any harmful effects due to the less than one degree C of global warming over the last century. there has been considerable anecdotal evidence suggested. much of it wrong. we here in the US were relentlessly warned after hurricane katrina that this was a sign of 'things to come'. we all know how that turned out. rising sea levels have not been empirically demonstrated to date. anecdotally yes. south sea islands going under? no. subsidence, yes. there has been no statistically significant increase in global temperature in the last *fifteen years* - all while china has increased its belchings of CO2 by many orders of magnitude. no, all i ask is that climate "science* give me something more concrete than ridiculous computer models with no basis in reality. all i ask is actual, verifiable PROOF that harm has occurred. now, does my skepticism mean i'm against reducing dependence on petroleum, that i'm against clean air? not in the slightest. it's likely that oil will run out someday. as a feedstock for a huge number of extremely important products that have made life better for all humans, i'm in favor of conserving petroleum for uses more constructive than driving about on a sunday afternoon. we need power to run our modern world - and we need to find alternatives. what i am against is extreme policies that can harm just as many people as global warming is claimed may be harmed. alarmism is harmful in itself. it does not advance the science or the argument. running about, screaming that the sky is falling, is not having the effect the promulgators desire. encourage conservation. work on creating the ultimate solar panel. be constructive, rather than alarmist, and you'll accomplish a hell of a lot more, and alienate a hell of a lot fewer people.
    0 0
  10. Anastrophe's post is nothing but a rote recapitulation of standard denialist dogma. Do we really need it here? Can't we at least have some creative skepticism?
    0 0
  11. @Anastrophe, I refer you to the It's not bad for a few examples on how a 0.15C rise per decade is dangerous. BTW, it's "alarmism" to be prepared to deal with bad stuff, it's survival. "Alarmism" is the term contrarians use to denigrate those who understand the scientific consensus. The truth of the matter is that alarmism is much less of a threat right now than is apathy.
    0 0
  12. I was trying to answer the question "Is it safe to double atmospheric Carbon Dioxide over a 200 year period" but rather than get bleeped, I will try a different approach. Atmospheric carbon dioxide concentrations have varied over a wide range since life appeared on land. For the sake of argument I suggest a range of 190 to 7,000 ppm, although the error bars at the high end leave plenty of room for debate. Modern CO2 levels are quite close to the low end of the range and even with a doubling will remain at levels that have been well tolerated by living things over hundreds of millions of years through both climate optimums and ice ages. So the answer to the question is "YES". The arguments for CO2 driven catastrophe arise from an inclination to see only negative consequences from changing conditions as if the status quo represents some kind of "golden age". The "fingerprinter" is guilty of making all kinds of statements that are contrary to what the science tells us. For example: "The first place to look is of course the paleoclimate record. Over the last several decades of research, the sensitivity of the climate system to changes in carbon dioxide has been established through ice core samples and other proxy climate indicators." The ice core records such as Vostok and GISP/GRIP show no such thing. To the contrary they show the sensitivity of carbon dioxide concentrations in the atmosphere to changing temperatures.
    0 0
  13. @gallopingcamel: looking at past values of CO2 is useless if you don't adjust it for lower solar input, as was the case when it was in the high end of that range. The last time CO2 concentrations were this high with a similar solar output, temperatures were 5 to 7 degrees warmer than today. So the answer to the question is really "NO". The "CO2 lags temperature" argument is also junk, as shown elsewhere on this site. Also, it would be nice if you admitted you were wrong about increased atmospheric CO2 automatically being good for plants.
    0 0
  14. @dhogaza, you offer nothing but rote dismissal of my comments. is it really necessary for you to attempt to dismiss my thoughts, rather than actually addressing them? @archiesteel, i just skimmed the article you directed me to. it has a lot of "might" and "may" and "could" to it; it provides no science to back up the anecdotal claims it makes. again, show me the proof that the small warming that has occurred has actually caused harm. not speculations about what might, may, could happen if we warm further. evidence of harm that has occurred. there is none as yet. only anecdote. and i'll note that the word alarmism well predates your colloquial claim that it's used to denigrate 'those who understand the scientific consensus'. show me what harm has occurred. show me how screaming that the sky if falling is useful.
    0 0
  15. anastrophe (@59), You make excellent points. Like you I want to improve the environment by limiting the pollution of our air and water. However, I don't see CO2 as a "Pollutant" given that all plants would die without it. From basic physics it is clear that CO2 concentrations in the atmosphere have an effect on radiative heat transfer but the experts are still arguing about the net effect on global climate after "feedbacks" are taken into account.
    0 0
  16. @anastrophe: please show me proof that the many recent extreme weather events have not been made worse by the increase of energy in the global weather system caused by AGW. Thanks. BTW, the Intermediate version of the "It's not bad" argument provides ample sources for you to educate yourself. @gallopingcamel: a pollutant is not simply determined by toxicity, but also by the harm it causes in large concentrations. Increased CO2 is harmful, and won't by itself help plant growth. As for the net effect of AGW, experts may disagree on details, but they pretty much all agree it will be bad.
    0 0
  17. @archiesteel: um, that's not how science works. science needs to show that recent extreme weather events have been made worse. so far, if it seems to support the AGW theory, then AGW proponents claim that weather events have to do with changing climate. if they don't support the AGW theory, AGW proponents claim 'that's weather, not climate'. witness the dismissal of last winter's record snowfalls in the US, and dismissal of this winter's crippling snow in europe - all called "just weather". a heatwave? why, that's not weather, that's clear and present proof of global warming! it's for those claiming that there is harm to show that harm has occurred. just like this article - which claims that it's about showing that rising CO2 is isn't safe, when all it addresses is that CO2 has risen. the sources in intermediate seem to all be talking about 'expected' harm. a typical example iis http://www.sciencemag.org/content/323/5913/447.short - "are the likely cause". i want science, not guessing.
    0 0
  18. "rising CO2 is isn't safe" - should be "rising CO2 isn't safe".
    0 0
  19. What about this post in WUWT: CO2: Ice Cores vs. Plant Stomata http://wattsupwiththat.com/2010/12/26/co2-ice-cores-vs-plant-stomata/ It states that: -Plant stomata suggest that the pre-industrial CO2 levels were commonly in the 360 to 390ppmv range. (source: Kouwenberg, 2004. APPLICATION OF CONIFER NEEDLES IN THE RECONSTRUCTION OF HOLOCENE CO2 LEVELS. PhD Thesis. Laboratory of Palaeobotany and Palynology, University of Utrecht.) -Plant stomata data show much greater variability of atmospheric CO2 over the last 1,000 years than the ice cores and that CO2 levels have often been between 300 and 340ppmv over the last millennium, including a 120ppmv rise from the late 12th Century through the mid 14th Century. (source: Kouwenberg et al., 2005." Atmospheric CO2 fluctuations during the last millennium reconstructed by stomatal frequency analysis of Tsuga heterophylla needles". GEOLOGY, January 2005.) -A recent study (Van Hoof et al., 2005) demonstrated that the ice core CO2 data essentially represent a low-frequency, century to multi-century moving average of past atmospheric CO2 levels.The stomata data routinely show that atmospheric CO2 levels were higher than the ice cores do. (source:Van Hoof et al., 2005. Atmospheric CO2 during the 13th century AD: reconciliation of data from ice core measurements and stomatal frequency analysis. Tellus (2005), 57B, 351–355.) This is not the tipical nonsensical stuff found in blogs like WattsUpWithThat. John Cook, what do you think about these studies that show high levels of CO2 in recent past? (By the way it seems like an interesting material for a post)
    0 0
  20. "This is not the tipical nonsensical stuff found in blogs like WattsUpWithThat. " Actually, yes, it is, and a couple of the more knowledgeable denialists over there point out why. Ferdinand Engelbeen's response, for instance.
    0 0
  21. Sorry, the paper's presumably not nonsense, but the WUWT post interpreting them is. Has WUWT ever been right about *any* paper they claim proves portions of climate science to be wrong?
    0 0
  22. #67: "show that harm has occurred." Consider looking around a bit before coming to what may be pre-conceived conclusions. Try the Extreme weather thread or Its freaking cold, for starters. "i want science, not guessing. " You may have heard that large portions of modern science are entirely concerned with the study of increasing and decreasing probabilities of various events. If you choose to call that 'guessing', that's your privilege. Although, I suppose you shouldn't use anything you have that uses LEDs or integrated circuits if you can't tolerate guessing.
    0 0
  23. " witness the dismissal of last winter's record snowfalls in the US, and dismissal of this winter's crippling snow in europe - all called "just weather". a heatwave? why, that's not weather, that's clear and present proof of global warming!" 1. heavy snowfall is not a reliable indicator of a colder winter. Nor'easters, for instance, get their moisture while traveling across the atlantic offshore of the southern US. When that portion of the atlantic warms, more moisture is evaporated into the storm system, which then dumps more snow when it hits the colder air inland and northward. 2. Parts of Europe during this cold spell have been having century events. The Russian heat wave, on the other hand, was unprecedented in the last 1,000 years, according to Russian scientists who have made proxy reconstructions of past climate conditions there. 3. Thus far December has seen extremely warm weather in the arctic. The push of warm air north has led to arctic air infiltrading part of Europe and part of North America. 4. As you can see, much of North America (and the US) has been warmer than normal, not colder than normal. Compare this to the fact that the 2010 meteorological year (Dec 2009-Nov 2010) has been the warmest on record, globally. 5. About twice as many record highs have been broken than record lows in the last few years. None of them individually point to global warming. The trend towards more high than low records being broken is however consistent with global warming, and inconsistent with global cooling.
    0 0
    Moderator Response: [Daniel Bailey] Fixed text.
  24. "Although, I suppose you shouldn't use anything you have that uses LEDs or integrated circuits if you can't tolerate guessing." Or godly-dice-rolling tunneling diodes ...
    0 0
  25. From Peru at 08:56 AM on 27 December, 2010 Peru, from a quick perusal of your link it seems that Dave Middleton is posting much the same stuff that he posted here under the topic Plant stomata show higher and more variable CO2 levels last summer. His arguments were not very convincing then and you might want to consider whether he has addressed the criticism from posters here, in his new post that you linked to.
    0 0
  26. anastrophe - you have to learn how science works before claiming "i want science". Scientists speak the language of probabilities, not absolutes. Scientists always use worlds like "likely" and "probable" and "possible". To claim that's not science simply reveals that you don't understand science. As for current harm, the WHO states "The global warming that has occurred since the 1970s was causing over 140,000 excess deaths annually by the year 2004." Now, I'm sure you'll call this an "anecdote" just like you'll call any evidence you don't want to believe an "anecdote", so I'm not going to waste time giving you more evidence. But more importantly, we're not worried about current temperatures. If the planet stopped warming right now, we'd be fine. We're worried about the potential for catastrophic climate change if the planet warms another couple of degrees. Your argument, aside from being wrong, is a strawman. From Peru #69 - the short answer is that plant stomata are an indirect and thus imperfect measurement of atmospheric CO2. More factors impact stomatal density than must CO2. That's why climate scientists use air trapped in ice cores to *directly* measure past CO2 levels, rather than stomata.
    0 0
  27. The second sentence in my last paragraph should read "...than *just* CO2". For more details see the link provided by chris in #75.
    0 0
  28. The stomata "issue" has has its own thread here. It should be noted that there are some issues with the papers in question that have been discussed elsewhere on SS. The "skeptics" continue with their incoherent ramblings.
    0 0
  29. dana1981 (@76), That WHO study is a good example of seeking out bad news while ignoring good news. Fortunately there are other studies with a more balanced approach that tell us what anyone with a grain of common sense already knows. Falling temperatures are much more dangerous than rising temperatures when we are talking "Climate Change".
    0 0
  30. A couple of points related to some posts here. 1. Rate of change needs to be considered in determining risk to society. Simply pointing to the total range of past CO2 changes is not sufficient. This also ignores that civilisation has only existed during the Holocene. 2. Climate science is not actually concerned with economics. Economic cost, or a cost benefit analysis of CO2 mitigation, is best left to other experts and should not influence the science. Our job is to define the physical risk posed by altering atmospheric chemistry. 3. I will note however that the cost of mitigation is poorly defined compared to the risks of CO2 increases over the next century. The literature on the economic cost is nowhere near as well developed as the scientific literature, so I would argue that it is the other side of the public debate that is being alarmist- by definition. Doubling atmospheric CO2 in 200 years is a drastic intervention in the climate system. If you claim mitigation is equally as drastic, then point to a peer reviewed body of work that has performed that analysis; i.e. has compared cost versus cost. 4. There is no way that governments would allow climate scientists to openly experiment with the climate system. If Chinese scientists proposed quadrupling atmospheric CO2 (from current concentrations) over 40 years, as a counter intuitive way to stabilize the climate system, and the Chinese government intended on immediately following their advice unilaterally (supposing it were possible), it is doubtful that people would retain their supposed confusion over unsafe until proven safe. The question then becomes, on what scientific basis would the rest of the world let them do it? I do believe that most of the skeptics I have come across would actually be in favor of allowing that course of action, since they believe that such a change in CO2 is unlikely to have a tangible effect on anything. There would be those however, that would suddenly becomes champions of the consensus literature.
    0 0
  31. dana1981@76: Stoma is not perfect to detect levels of co2, and ice core samples are not perfect either. There is considerable literature showing that ice cores difuse much more than previously thought. The error bars indicate that recent past co2 could have been as low as 195ppmv or as high as 395ppmb. This is in line with the stoma research.
    0 0
  32. gallopingcamel #79 - I've found that uninformed "common sense" is usually wrong. Anyway we're not talking about falling vs. rising temperatures. We're talking about rapidly rising vs. hopefully stabilizing temperatures. Camburn #81 - my philosophy is not to believe what random people on the internet say unless they're able to provide supporting evidence. If there is "considerable literature", surely that won't be a problem.
    0 0
  33. #79: "Falling temperatures are much more dangerous" We've been through this elsewhere on SkS; you can find it if you search. The research says it's about a wash. The major difference being hot weather health effects are more immediate; cold weather effects take longer to make a statistical impact, if I recall correctly.
    0 0
  34. Actually, we went through this specific issue with GC on the Canada thread, specifically comments 51-72 (changes in Cold-Related-Mortality vs changes in Heat-Related-Mortality in a warming world). The Christidis et al study, IIRC. Human adaptation to cold is better than to warm. We can always burn enough CO2 to keep the ice ages at bay. Unfortunately, due to the rising obesity trends, there's a limit to modifiable behaviours to deal with heat and humidity. JunkScienceCO2Science is a big disinformer site. The Yooper
    0 0
  35. "There is considerable literature showing that ice cores difuse much more than previously thought." Well, Camburn, provide references that support your case. Hopefully ones that spell "Diffuse" correctly. And are published in reputable venues.
    0 0
  36. #84: Oh, Canada! Wasn't that the place where the warming is much faster than the global average? The slope of the 30-year trend in this region is 5 to 6 C/century -- a rate of warming that's much higher than the rest of the world. Happy holidays to you and yours!
    0 0
  37. Re: muoncounter (86)
    ♪♫♪♫ "Oh, Canada, where the acid-rain falls freely on the oil-shale-besotted plains..." ♫♪♫♪
    (with nary a dint of effort, I can turn any tragedy into a Rodgers and Hammerstein musical) We should be so lucky to get the full 200 years of this post to double our atmospheric concentrations of CO2... Thanks for the kind words & same to you, muoncounter, same to you. The Yooper
    0 0
  38. @anastrophe: "@archiesteel: um, that's not how science works. science needs to show that recent extreme weather events have been made worse." Science does not respond to your whim. Science tries to explain observed phenomenon. What to do about what science tells us is another matter entirely. "so far, if it seems to support the AGW theory, then AGW proponents claim that weather events have to do with changing climate." No, they don't. Weather is weather, and climate is climate. Don't use strawman arguments if you want to be taken seriously. "witness the dismissal of last winter's record snowfalls in the US, and dismissal of this winter's crippling snow in europe - all called "just weather". Indeed, because when you focus on just these events (i.e. cherry-picking) you don't get the correct picture. Climate is global, and so you must look at global temperatures. Last winter was warmer than average globally, and the coming winter probably even so. Sorry for completely destroying your argument, but is *is* pretty old. "a heatwave? why, that's not weather, that's clear and present proof of global warming!" Strawman argument. No one says this. "it's for those claiming that there is harm to show that harm has occurred." Tell that to residents of the Maldives. "Hope for the best, expect the worst" is the best survival strategy. If it were up to you, we'd wait until the whole neihborhood was ablaze before calling the fire dept.
    0 0
  39. @Camburn: "Stoma is not perfect to detect levels of co2, and ice core samples are not perfect either." Ice cores are a lot more precise than plant stoma. "There is considerable literature showing that ice cores difuse much more than previously thought." Not really. "The error bars indicate that recent past co2 could have been as low as 195ppmv or as high as 395ppmb. This is in line with the stoma research." Do you have sources to support these affirmations?
    0 0
  40. @gc: "Falling temperatures are much more dangerous than rising temperatures" We're not dealing with falling temperatures.
    0 0
  41. The role of the sceptic is to point out the flaws in the popular comments on AGW, of which this thread is a good example. If you see a signpost pointing in the wrong direction, you perform a service by taking it down. There are several different popular theories of AGW, and like all “scientific” theories they stand or fall on the principle of falsification. As Einstein said, 20,000 observations may confirm a theory – it only takes one to refute it. Here are three: 1) One view of AGW (which I suspect caerbannog 28 favours)is that CO2 will accumulate in the cold, dry, upper atmosphere where water vapour cannot interfere with its impact. The energy absorption in this region will increase rapidly because CO2 will be the principal “greenhouse” gas. The temperature increase will then cascade through lower layers, warming the surface. You can test idea this by comparing the UAH satellite temperature trends over the last 30 years: Lower troposphere ; 1.4 degrees C per century Upper troposphere : 0.5 degrees C per century, a factor of almost three in the wrong direction 2) Another popular theory is the “back-radiation” idea. A single-slab model of the atmosphere will absorb heat from the surface, radiate half to space, and half back to warm the ground. Relative to a bare rock earth, the surface must radiate double the energy, because the output to space from the atmosphere must be the same as the solar input. To achieve this, the surface temperature must increase by a factor equal to the fourth root of 2, or 19%. From a bare rock temperature of 255 K, this theory gives an increase of 48 degrees C, which is plausible. To test this theory, RWWoods built his greenhouses. One, made of glass, absorbed outgoing radiation. The other, made of salt, did not. There was no measurable temperature difference in the interiors. 3) All CO2 based AGW theories depend on the ability of CO2 to absorb energy. If the molecules could trap and transfer heat to the atmosphere, increasing the CO2 concentration in air would generate steadily increasing temperatures. Angstrom (he of the unit) tried it. He found that, as soon as all the available energy output from a source had been absorbed, temperatures in the air ceased to rise. You can see a comparison of air (385 parts per million) and 100% CO2 here: http://www.espere.net/Unitedkingdom/water/uk_overview.htm
    0 0
    Moderator Response: [muoncounter] Vastly off-topic, which quickly leads to deletion. All three of your 'signposts' are thoroughly discussed and dismissed in other threads. Try using the search box to find more appropriate places if you want to rehash these denial 'chestnuts'.
  42. Please take the stomata-CO2 variability red herring "argument" here. And again, the spin that some faux science web sites have tried to put on the papers is nothing more than spin. And I doubt that any of the "skeptics" here have actually read the papers with a skeptical eye. Really, the incessant whining, strawmen, red herrings and other diversionary tactics employed by the contrarians and wanna-be "skeptics" is now getting highly annoying.
    0 0
  43. For those trying to argue that people have not been dying becasue of anthropogenic climate disruption, please consider the wise words of Dr. Kevin Trenberth to the New York Times recently: "It’s not the right question to ask if this storm or that storm is due to global warming, or is it natural variability. Nowadays, there’s always an element of both." Also research has shown that anthropogenic climate disruption played a role in the European heat wave which killed about 40 000 people. And preliminary statistical analysis and has shown that the Russian heat wave (which also killed thousands) was probably also, in part, attributable to climate disruption. And there are more examples where those came from.
    0 0
  44. In regards to Trenberth's quote of "there's always an element of both," this should make people even more concerned about small changes in global temperature. When you take that naturally variable signal, one with a number of peaks and troughs each year, then you turn the knob so that the overall signal is higher... that means you end up with much higher peaks and troughs that don't reach quite as low. And I think this hits straight to the heart of the safely issue that this thread is supposed to be about. It's that variability in the rising signal that is going to cause the most disruption. The 2C global average is not going to hurt anyone (optimistically hoping we can keep it below 2C), but the amplified peaks are going to get very very ugly.
    0 0
  45. See also the Extreme weather thread, especially the Hansen quote here.
    0 0
  46. Is there any point in reducing my "carbon footprint" by 50% (even if I could) if the Earths population is set to double in the next 50 or 100 years ? Surely carbon use is an effect and population growth a cause, and not one which politicians will relish tackling ?
    0 0
  47. #97: "Is there any point in reducing my "carbon footprint"... " Some would call it 'leading by example' and argue its the right thing to do. Some would say you'd be contributing to wider causes (energy independence included). But if not, I suppose we could all say the same thing and justify going on with business as usual. The climate forecasts for that scenario are very unpretty. You should be aware that the developed world has the highest emissions per capita. Most of the population growth is in places where the per capita rate is much smaller. Here is a prior thread for this discussion.
    0 0
  48. I'm not against reducing energy dependence, being more efficient or saving the planet's resources, as that all seems quite sensible. I am against "leading by example" if it's not a good example. Trying to deal with an effect if the underlying cause is not dealt with, and is increasing at an alarming rate, isn't going to help. I take the point that the developed world has the highest emissions, but as the rest of the world develops, their emissions will increase too. By the time the population reaches 15 or 20 billion, many more will be highly developed, using plenty of fossil fuel and with not much of the stuff left (maybe that's when we'll stop using it !!) I know there are no easy answers, as disease and pestilence (and maybe war to a lesser extent) have been the only things to reduce populations significantly in the past. However if we keep bleating about carbon footprint whilst ignore population growth we will achieve exactly nothing, or worse.
    0 0
  49. The developing nations do not have to follow the same industrialization path that the developed nations did. They have clearly stated that they will not change for us but with us. Refusing to change because they might not is playing a game of chicken that there is no benefit in winning. Focusing on population growth only delays the inevitable. Population is not the issue; what the population does is.
    0 0
  50. I wouldn't refuse to change, I try - I've walked to work several times recently, and wear a pullover and turn down the heating. I think changing our lifestyle drastically would help. But.... 1800AD - less than 1 billion people 1900AD - more than 1 billion people 2000AD - 6 billion 2100AD - ??? (i'm thinking it's not linear) Don't deal in cliches, do the math What nations/governments etc "have clearly stated" may not happen. Population is the issue. 300 million people in 1000AD caused no global warming (did they cause the little ice age by not keeping enough cattle to produce enough methane ?)
    0 0

Prev  1  2  3  Next

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us