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Preventing Misinformation

Posted on 22 March 2011 by dana1981

A few individuals and groups have queried Skeptical Science about a misleading and myth-filled climate page from  The page is actually a re-post of a document put together by amateur astronomer Gregg D. Thompson.  We at Skeptical Science aim to please, so here we will examine the claims made in this document.  Since it consists almost entirely of long-debunked myths, most of our response will consist of linking to existing rebuttals in the Skeptical Science database.  Unfortunately, but unsurprisingly, the document contains no supporting evidence or references, so we will evaluate its arguments on their own merit (and lack thereof).

Human Emissions are Small

The document begins by making a number of irrelevant and misleading statements about human carbon dioxide (CO2) emissions.  The three principle misleading statements and errors are:

"CO2 is less than a mere four 100ths of 1% [of the atmosphere]"

"Humans produce only 3% [of global CO2 emissions]"

"If the public were aware that man-made CO2 is so incredibly small there would be very little belief in a climate disaster"

These statements presume that anything that is present as a small proportion can have no effect, which is clearly nonsense.  In reality, the percentages of CO2 in the atmosphere and of human CO2 emissions are irrelevant to the risk that those emissons pose. A very small proportion of arsenic in drinking water can be very dangerous, for example. 99% of the atmosphere is composed of non-greenhouse gases, so the entire greenhouse effect is caused by the remaining 1%

The second statement ignores the fact that although natural emissions are much larger than human emissions, the natural carbon cycle is in balance.  Natural carbon sinks absorb more than natural carbon sources emit, and human emissions upset that balance.  That's why humans are responsible for the 40% increase in atmospheric CO2 over the past 150 years.

CO2 as a Pollutant

"CO2 is a harmless, trace gas. It is as necessary for life - just as oxygen and nitrogen are. It is a natural gas that is clear, tasteless and odourless. It is in no way a pollutant."

They key to qualifying as a "pollutant" is whether it poses a threat to public health and welfare.  CO2 clearly creates this threat through climate change, and thus qualifies as a pollutant.  The fact that CO2 is colorless, tasteless, and odorless is completely irrelevant.  The argument that CO2 is necessary for life, implying that it therefore can never cause harm, is nonsense.  Water is equally necessary for life, but too much of it can be fatal.

The Greenhouse Effect

"There is no proof at all [that CO2 causes a greenhouse effect]. The Intergovernmental Panel for Climate Change (the IPCC) has never produced any proof. There are, however the following proofs that it can’t cause a greenhouse effect."

The fact that CO2 is a greenhouse gas has been known for over a century.  John Tyndall measured the CO2 greenhouse effect in laboratory experiments in 1859.  To claim that there is no proof that CO2 causes a greenhouse effect is, to be blunt, a sign of extreme ignorance regarding basic climate science, and a red flag that Thompson and have not done their homework.

"It is true that CO2 can absorb heat a little faster than nitrogen and oxygen but it becomes no hotter because it cannot absorb anymore heat than there is available to the other gases. This is against the laws of thermodynamics."

If this argument were true, the greenhouse effect would not exist, which is obviously not the case.  It has been debunked in The Greenhouse Effect and the 2nd Law of Thermodynamics.

"Even if CO2 levels were many times higher, radiative heating physics shows that it would make virtually no difference to temperature because it has a very limited heating ability. With CO2, the more there is, the less it heats because it quickly becomes saturated."

The document goes from arguing that CO2 is not a greenhouse gas, to arguing that the greenhouse effect does not exist, to arguing that the greenhouse effect exists, but atmospheric CO2 is saturated.  The number of self-contradictions is rather appalling.  Regardless, the atmospheric CO2 greenhouse effect is not saturated.  Adding more CO2 to the atmosphere effectively adds more layers to absorb outgoing infrared radiation and re-emit some of it back towards the surface, increasing global warming.

More Greenhouse Misunderstandings

"The planets Venus and Mars have atmospheres that are almost entirely CO2 (97%) yet they have no ‘runaway’ greenhouse heating effect. Their temperatures are stable."

The temperatures of Venus and Mars are stable because the amount of CO2 in their atmospheres is stable.  A "runaway greenhouse effect" occurs when something warms the planet, triggering positive feedbacks which warm it further; however, even this  does not mean the planet continues warming infinitely, forever.  In fact, positive feedbacks do not necessarily lead to 'runaway warming'

Venus appears to have undergone a runaway greenhouse effect long ago in its history, but has now stabilised.  Venus is twice as hot as Mercury, despite being twice as far from the Sun, in large part because of the greenhouse gases in its atmosphere.  And Mars isn't particularly hot because its atmosphere is thin and has little water vapor - another greenhouse gas.

"The geological record over hundreds of millions of years has shown that CO2 has had no affect whatsoever on climate. At times, CO2 was hundreds of times higher, yet there were ice ages."

CO2 is not the only factor which impacts global temperatures, but to infer that it therefore cannot have any effect is nonsense, akin to saying that not all deaths are due to cancer, therefore no deaths are due to cancer. 

Over billions of years, the Sun has become gradually brighter.  Over millions of years, movements of continents and the rise and fall of mountain ranges has had great effects on our climate.  Over tens of thousands of years, Milankovich cycles have increased and decreased seasonality, leading to periods of greater ice cover which in turn reflect away sunlight, cooling the planet.  However, through it all the geologic record tells us that the climate is quite sensitive to CO2, and that CO2 is the principle control knob for the Earth's temperature.

Medieval Misinformation

"Earth was considerably warmer during the Roman Warming and the Medieval Warming"

This is simply false.  Every peer-reviewed millenial temperature reconstruction shows current temperatures hotter than during the Roman and Medieval periods.

Water Vapor

"Water vapour is 4% of the air and that‘s 100 times as much as CO2. Water vapour absorbs 33 times as much heat as CO2 making CO2’s contribution insignificant."

Water vapor is a feedback, not a forcing.  Furthermore, as Lacis et al. (2010) found:

"Because carbon dioxide accounts for 80% of the non-condensing GHG forcing in the current climate atmosphere, atmospheric carbon dioxide therefore qualifies as the principal control knob that governs the temperature of Earth."

Winter Temperatures

"Over the last few years Earth has had much colder winters"

This is another blatantly false statement.  The average global surface temperature continues to rise during every season.  In fact, winters are warming faster than summers!


Arctic Ice and Glaciers

"the Arctic has re-frozen and glaciers that were receding are now surging due to the heavy snow falls."

Once again, the document makes completely false assertions.  Arctic sea ice continues to decline rapidly, as does global glacier mass.

Blaming the Sun

"as the Sun is now entering probably 2-4 decades of low solar activity, this is expected to cause global cooling."

Solar activity has been flat over the past half century, during which time global surface temperatures increased over a half degreee Celsius.  The Sun is not driving global temperatures.

The 1934 Myth

"The hottest records in the USA and Greenland were in the 1930s due to a strong solar cycle."

First of all, the USA and Greenland are not the world.  The global surface air temperature is currently approximatley 0.6°C hotter than it was during the 1930s.  Secondly, today's temperatures are hotter than the 1930s even in the USA and Greenland.

Mid-Century Cooling

"It became cooler from 1940 to 1970. This was due to a weak solar cycle."

The mid-century cooling was not caused by the Sun.  In fact, solar activity increased slightly between 1940 and 1970.

Recent Temperatures

"It has again become increasingly colder since 2006 due to another weak solar cycle."

Although five years is far too short of a timespan to determine a significant trend, the trend since 2006 is positive (warming).  2009 and 2010 were two of the hottest years on record, despite the weak solar cycle.


"We were told CFCs caused the Ozone ‘hole’ yet after billions of dollars were spent removing CFCs over 30 years, the slight depletion of Ozone at the South Pole has not changed. Scientists now think it is natural."

The ozone layer is recovering, and scientists still think its depletion was caused by human chlorofluorocarbon (CFC) emissions, because that's what the scientific evidence indicates.   However, we only started seriously reducing CFC emissions 20 years ago (with the Montreal Protocol - the ozone version of the Kyoto Protocol), and CFCs have a long atmospheric lifetime, so the recovery will take time.  There are of course ozone "skeptic" scientists just like there are global warming "skeptic" scientists, but the consensus and evidence are not in their favor.

Carbon Pricing

"A carbon tax will have a disastrous impact on lower and middle income earners."

Fear of a carbon tax may be the underlying motivation behind this ill-conceived document.  However, the benefits of carbon pricing outweigh its costs, and results in smaller economic impacts on lower and middle income households.

Gish Gallop City!

As you can see, this document is little more than a Gish Gallop of Moncktonian proportions.  It's merely a result of Thompson not taking the time to learn some basic climate science, putting together a document full of misleading misunderstandings and misinformation, and propagating that misinformation.

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Comments 1 to 50 out of 72:

  1. We should also prevent these myths: 1. Global warming is 'worse than expected' Since 1979, satellite and surface measurements indicate warming trends at less than the IPCC best estimate for the "low" scenario. 2. Global warming is 'unprecedented' The period from 1910 to 1945 ( thirty five years ) had the same surface temperature trends ( CRU and GISS ) as the period since 1979. 3. Global warming is accelerating. Temperature trends for most of the satellite and surface records are lower from 1995 to present than they are for the period 1979 to present. Temperature trends for ALL of the satellite and surface records (RSS,UAH,CRU.GISS)are lower from 2001 to present than they are for the period 1995 to present.
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  2. I think it needs to be made clear that humans produce nearly 100% of the NET annual global increase in CO2 emissions, and the 3% [of global CO2 emissions]" refers to human contribution to TURNOVER, a largely irrelevant quantity.
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  3. ClimateWatcher #1 - you are incorrect. The warming is well within the IPCC range of projections, and the current warming trend is larger than the early 20th century trend. perseus #2 - was that not clear?
    "although natural emissions are much larger than human emissions, the natural carbon cycle is in balance. Natural carbon sinks absorb more than natural carbon sources emit, and human emissions upset that balance. That's why humans are responsible for the 40% increase in atmospheric CO2 over the past 150 years."
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  4. dana1981: You may wish to alter this phrase: "Over billions of years, the Sun has become gradually dimmer."
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  5. Dana - A nice little summary of refutations of almost all the major denier idiocies. It amazes me that such clearly idiotic documents are still being put up on the web.
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  6. Climatewatcher, whether the current warming is unprecedented or not is irrelevant to determining the cause. It's only relevance is when it convinces us to investigate the cause, which it has done. You can actually drop the concern over the shape of the hockey stick, our investigations independent of that shape show a human fingerprint.
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  7. @KeenOn350- If your approach to political science were as scientific as your approach to climate science, (or even just as close as scientific as possible, for those quibblers who deny that it is a science), you would not be surprised. This is situation NORMAL. Most people just do not understand the idea of believing only what is proven, by the best 'scientific' method available, to be true. On the contrary: they have a strong habit of first deciding what they want to believe, and then looking for 'facts' that encourage them to persist in this belief. In fact, it takes many people long training in the scientific disciplines to overcome this habit. Not even all scientists do. Remember Linus Pauling on Vitamin C? Or Einstein's denial of the Copenhagen interpretation of quantum mechanics? But what I really wanted to say is that though the point by point refutations in this article are all good, and I will no doubt remember some of them, what REALLY sticks is that excellent summary of the whole mess to be refuted: "Gish gallop of Moncktonian proporations"! Now THAT will stick, but only because I already know who Monckton is and what a "Gish gallop" is.
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  8. Nick #4 - thanks, good catch. Keen #5 - Thanks. It doesn't surprise me that this sort of junk is put on the web. What bugs me is that anybody takes it seriously! MattJ #7 - thanks, I previously used the phrase for Lubos Motl, but it applies even better to this document.
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  9. #6 - Gary "our a human fingerprint." What finger print(s) do you refer to? There should be warming due to increased CO2. I'm on board with that. But the only 'fingerprint' of the models that I know of is stratospheric cooling. And stratospheric cooling HAS occurred. But there's some nuance. Most of the stratospheric cooling since the MSU era began can be accounted for by the two 'step function' temperature drops associated with the Volcanic eruptions ( El Chichon and Pinatubo ). The years preceding the eruptions and the trend in the lower stratosphere since Pinatubo resolved ( say 1995 ) are warming or flat. Still, the trend is consistent with CO2 forcing, but is there another finger print you are thinking of?

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    [dana1981]There are many anthropogenic global warming fingerprints

  10. Thompson in his first answer writes "the vast bulk of the population have very little knowledge of science so they find it impossible to make judgements about even basic scientific issues let alone ones as complex as climate. This makes it easy for those with agendas to deceive us by using emotive statements rather than facts" So he got something right
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  11. Mr Thompson forgot "Al Gore is fat". But seriously, I really hope he and the other "climate skeptics" are right. I would love to still be skiing the Salamander and Stanton Glaciers in late summer ten years from now. I have even allowed myself some hope as I have seen them gain snow the last few years. Nothing exposes this hope as vain and deluded like the arguments used by the various "skeptics" reported and posted here. The endless repetition of long ago destroyed arguments, the repeated proof of the D-K effect, the inability to find facts a bicycle mechanic (me) can find in seconds scares me as much as any projection made by "warmists".
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  12. MattJ
    Or Einstein's denial of the Copenhagen interpretation of quantum mechanics?
    OT but a pet peeve of mine. Einstein was not in denial over the Copenhagen Interpretation. He was skeptical in the best scientific tradition. His skepticism led to the formulation of the EPR paradox, which, although it hasn't led to any widely accepted global interpretation of QD providing an algebraic, as opposed to probabilistic, solution to quantum wave function collapse as Einstein had hoped, did demonstrate the incompleteness of the Copenhagen Interpretation, and has led to profound discovery and ongoing research in QD.
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  13. #3. Hmmm.... my follow up post was evidently dropped, so I'll repost... <snip>

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    [dama1981]Your comment is off-topic.  If you wish to continue this argument, please do so in "IPCC overestimates temperature rise".

  14. CW also needs to read this and this for edification purposes. The Yooper
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  15. Dana, is it possible to get a graph whih resolves the NH winter temperatures and the SH winter temperatures. The one you show only resolves temperatures by months, and of course the NH winter is the SH summer.

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    [DB] Tom, you may find some of what you're looking for here and here.

    The Archives may have more, I just linked the one I remembered.

  16. Good point Tom. That was very northern hemisphere-centric of me!
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  17. ClimateWatcher at 03:17 AM on 22 March, 2011 "2. Global warming is 'unprecedented' The period from 1910 to 1945 ( thirty five years ) had the same surface temperature trends ( CRU and GISS ) as the period since 1979." Prove it. Do note that I am the author of the following post which disproves your argument. Unless you can show me where I calculated the differences in warming rates wrong then your argument is null.
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  18. Climate Watcher, your claims are demonstrably *false*. I've got the GISSTemp data right in front of me, & the warming rates I get are as follows: 1910-1945=+0.125 degrees per decade; 1975-2010=+0.176 per decade. So the current warming is already unprecedented compared to the warming of the first half of the 20th century. Of course, it's even *more* unprecedented when you consider the fact that 1910-1945 was against the backdrop of rising Sunspot numbers, whereas 1975-2011 has been against a backdrop of *falling* sunspot numbers. Epic *fail* there Climate Watcher.
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  19. Ever feel like you're bashing on the same points, over and over again, only to hear the same irrational rejection of information? At this point, the AGW deniers still refuting the above simply don't care for evidence as far as I'm concerned.
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  20. In a court of law, the jury is presented with "factual evidence" and it is the job of the prosecution or defense to discredit it with expert testimony. When one side attempts to reintroduce previously debunked evidence, the other side can object, then is is up to the judge to sustain or overrule the objection in order that the case may proceed. In some instances the judge will address the jury directly telling them they must forget something just presented. But climate science is being debated "in the court of public opinion" rather than "a court of law" and it seems to me that that many non-science people feel the need to reintroduce the same non-sense debunked yesterday. They do this because there is no professional immediately available to raise an objection, or any judge to recognize what is going on then admonishing the participants in order to move things along. I fear that I.Q. levels on planet Earth have just dropped 20 points in the past 20 years and humanity will continue to go round-and-around on the climate warming issue until some wise Solomon steps in a makes a paternalistic decision for us. p.s. this constant rehashing not only happens in the field of climate science, I am told that patent clerks still get thousands of submissions each year for what one would commonly called "a perpetual motion machine" from poor sods with no understanding of the first and second laws of thermodynamics.
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  21. So called scientists keep introducing the Global Mean Temperature even using basic physics its quite easy to show its a scientific nonsense- its maths without context.
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  22. cloa513, I'm sure we've had this conversation before. Statistical averages are useful in many, many contexts. Number of children per family changing from 4.1 to 2.7 does not mean we've found a way to create fractional children. Reducing needed doses of a medication from 8.3 to 6.1 of a standard dose tablet does not mean that lots of people waste endless hours precision cutting tablets. Reducing the amount of land needed to produce a standard quantity of grain does not mean farmers are shaving slices off paddocks. But numbers like these do tell us really useful things about societies or medical practices or agriculture. Same for average global temperature. It's a useful indicator, it's not a detailed diagram of any particular thing.
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    Moderator Response: [DB] You have a good eye and sharp memory. Checking, cloa513 has made 12 comments here at Skeptical Science on various threads. All 12 are variations on "we-can't-know-anything-it's-not-us-temps-are-unreliable-yadayadayada..." memes. Gold to adelady; Silver to scaddenp. :)
  23. cloa513, you seem to be trying hard to make this same point in the wrong place. How about posting this in temp record is unreliable, but be sure to read the resources there first. Especially, you should read the papers on how global temperature is determined. Its not done the way you seem to think it is and the methodology actually used is backed by a lot of actual research. Tamino's article pointed to there, can be found here (link in article broken).
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    Moderator Response: [DB] I've just updated the Tamino links in the article you link to. Thank you for pointing out the bad links.
  24. cloa513 - no, they talk about global mean temperature anomalies, which are by no means scientific nonsense. If you don't understand the difference, let me see if I can explain it simply for you (and any other readers who might be swayed by your words): If it's 1.3ºC warmer than average in Nairobi, and 1.3ºC warmer than average in Oslo, does that tell you something useful & meaningful? Even though it might be 35ºC in Nairobi but only 13ºC in Oslo? Obviously, you want to take more than just the values for any given day, to get a broader picture, and avoid "noise" in your data. That's done by averaging the values both geographically and over time. Otherwise, you'd be putting even more significance on things like a town in northern Canada having temperatures 30ºC above average back in January... (no, that is not a typo!)
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  25. Thompson said:
    It is a natural gas that is clear, tasteless and odourless.
    Hey, just like carbon monoxide! P.S. "principle errors" should be "principal errors".
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  26. Please delete this if my maths is wrong,but the denialist figure of a "mere 0.004 of 1%" always worries me. Surely 0.004 of 1% is the same as .00004%. But 400 ppm carbon dioxide (which is probably the source of the figure) is .04%. If we were talking blood alcohol, we would be talking almost illegal quantities.
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  27. Climatewatche: Your response is quite telling. The main thrust of my post was the relevance of past warming but you jump on fingerprints with a couple of denialist talking points. I take it from that you agree past warming is irrelevant to the current situation? cloa513: I take it you got that talking point from a denialist site? Care to expand a little on what it means?
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  28. RE: That's why humans are responsible for the 40% increase in atmospheric CO2 over the past 150 year. The conc of CO2 is presently ca 390 ppmv, but this value is _valid_ only for purfied dry air (PDA) which is comprised of nitrogen, oxygen and the inert gases, which are the fixed gases, and CO2. The conc in real air is always less due the presence of water vapor and clouds whose droplets contain CO2 and which alter the local conc of CO2. Real is the term for local air at the intake ports of air separation plants and contains the fixed gases, CO2, water vapor, reactive gases (e.g., oxides of sulfur and nitrogen), volatile organic compounds from natural sources (e.g., plants)and from human sources and activities (e.g., painting, gasoline, cooking, warfare, etc) and aerosols. For PDA at STP, there are 390 mls, 17.4 mmoles, 0.766 g,or 0.000766 kg of CO2 per cubic meter which has a mass of 1.2929 kg. For tropical air at 100% humidity and 32 deg C the density is 1.096 kg per cubic meter and the conc of CO2 is ca 372 ppmv. If PDA is cooled to 220 K, there is 21.6 mmoles of CO2 per cubic meter at one atmosphere pressure, and the conc is 390 ppmv since there is no water vapor. It PDA is heated to 330 K, there is 14.6 mmoles of CO2 per cubic meter at one atmosphere, and the conc of CO2 is 390 ppmv since there is no water vapor. The increase of CO2 in air is due in part to agriculture. For example, tillage of soil expose humus which oxidixes to CO2. Fertilization promotes the growth of microbes, worms and grubs which only respire and give off CO2 which they die and decompose. What does all of the above boil down to? It means that not only is there less CO2 in free real air than is indicated by analyses, we don't know the mass of CO2 in free real air nor its distribution in space and time.
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  29. RE# 28 h pierce: Scientists have an increasingly better understanding of the transport properties of CO2 through space and time. Unless you care to cite some research that shows otherwise? I suggest moving discussion over to the thread: CO2 measurements are suspect Watch the animation video at the bottom to see how scientists can watch CO2 mix throughout the atmosphere. More videos and explanation here
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  30. If I moved my comment to the CO2 measurement thread, nobody would read it. That video is for free CO2, and the conc is referenced to dry air. "Unless you care to cite some research that shows otherwise" Look at weather map on the TV. High pressure cells have more regional mass and more CO2 per unit volume than do low pressure cells. The map show there is no unifrom distributionn of pressure in space and time. Sat images show no uniform distribution of clouds in space and time. How much CO2 is in the droplets? it is not zero.
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    Moderator Response: Yocta is right. Your detailed discussion of this topic belongs on that other thread. You are wrong that no one will read your comment there, because most regular readers monitor the Recent Comments page you can see by clicking the Comments link in the horizontal bar at the top of the page.
  31. h pierce at 18:38 PM, this paper may be of interest to you. Mechanisms for synoptic variations of atmospheric CO2
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  32. For me, one of the most remarkable claims in the document was: "If the public were aware that man-made CO2 is so incredibly small there would be very little belief in a climate disaster" This indicates clearly that [--snip--] have given up refuting climate science directly, and are openly trying to destroy public trust instead. We all knew that this was what they were about, but this sentence contains a rare admission of guilt.
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  33. What struck me most about Thompson's article was how markedly the 'answers' he reported having received varied from my own mental responses; Q: What percentage of the atmosphere do you think is CO2? A: About 0.04%. Q: Have you ever seen the percentage given in any media? A: Yes. Several times per year as a percentage, daily as 'parts per million'... which anyone who knows how to divide can convert into a percentage. (390 / 1,000,000 = 0.039%) Q: What percentage of the CO2 is man-made? A: About 30% (i.e. (390 - 280) / 390 = 0.28) Q: What percentage of the man-made CO2 does Australia produce? A: A little over 1% per year currently. Maybe 2% of the accumulated total increase thus far. Q: Is CO2 a pollutant? A: Depends on the location and concentration... just like anything else. Currently atmospheric CO2 is a global pollutant. Q: Have you ever seen any evidence that CO2 causes a greenhouse effect? A: Sure... Tyndall measurements 1850s, lunar IR measurements at different latitudes, countless temperature and CO2 correlations in the instrumental and proxy records, the Earth not being a giant frozen ball of ice, et cetera. The sad thing is that he can only get away with such nonsense because the (wrong) responses he reports having received are plausible. If people were educated on the issue then charlatans like this would be unable to gain any traction. Sadly too much of the population goes out of the way to 'educate' themselves with pure fiction. The good news is that children in schools, who will eventually be in a position to do something about it, are instead taught reality... though I know in the U.S. there are increasingly strident efforts ongoing to change that.
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  34. “... the natural carbon cycle is in balance ...” „Natural carbon sinks absorb more than natural carbon sources emit, and human emissions upset that balance. That's why humans are responsible for the 40% increase in atmospheric CO2 over the past 150 years.” ... there's no indisputable evidence ..., ... and it is not so simple. In nature, this model is dominated: model of an oscillating - Lotka–Volterra equation Imagine that in the atmosphere from natural sources (imbalance - as a result of global warming - between sources and the sinks CO2 - the excess of sources over sinks) in the pre industrial era (exit of the LIA), 2 ppm CO2 goes unbalanced. Ie. if we assume that there was an increase of 5 ppmv natural CO2 - respiration, ocean ventilation - (hypothetical value) per annum (the beginning of the industrial era). 2 ppmv CO2 is added to the atmosphere each year as "permanent" surplus. Add to that “our” 5 ppm of CO2 emissions. In general - in all - it should be 7 ppm unbalanced surplus? Nothing could be further from the truth. Assuming that the optimum of photosynthesis in the range 400 - 600 ppm CO2, any new source of CO2 strongly reinforces - is intensifying photosynthesis. However, there is the emergence of a new source of anthropogenic CO2 in the industrial era. New source - new 5 ppmv CO2 adds to the atmosphere - is to improve conditions for photosynthesis, the biosphere. These "next" source so the biosphere reacts more positively than those earlier. These new - an additional anthropogenic source - increases of NPP is not a 3 ppmv but about 4.5 ppmv - increase bio-sinks. In other words, an increase in sources of CO2 by 10 ppmv - biosphere absorbs 7.5 ppmv increase from both sources. Without anthropogenic CO2 source is unbalanced excess of 2 ppm of CO2 + A. CO2 = 2.5 ppm. A. CO2 = 0,5 ppm ... Such a scenario is possible - we have to prove it - a fact - but it's not disinformation. The First-Order Effect of Holocene Northern Peatlands on Global Carbon Cycle Dynamics, Wang 2010.: “Holocene anthropogenic hypothesis is to claim that humans took control of atmospheric CO2 and CH4 trends thousands of years ago because of perturbations from land-use and land-cover changes [13-15]. However, without constrained magnitudes of those changes, it is still difficult to add this hypothesis into our model simulations.Variations in temperature sensitivities of soil and microbial respiration: Implications for climate-carbon modeling, Suseela et al., 2010.: “Soil respiration is the largest flux of carbon dioxide to the atmosphere, releasing more carbon than fossil fuel combustion. Since temperature affects soil respiration, on a global scale, even a small warming-induced increase in carbon dioxide emission from soils could act as a positive feedback to climate change.” Temperature sensitivity of soil carbon fractions in boreal forest soil, Karhu et al. 2010.: “Still, the temperature sensitivity is not known for the majority of the SOC, which is tens or hundreds of years old. This old fraction [14C !] is paradoxically concluded to be more, less, or equally sensitive compared to the younger fraction. Here, we present results that explain these inconsistencies. We show that the temperature sensitivity of decomposition increases remarkably from the youngest annually cycling fraction (Q10 < 2) to a decadally cycling one (Q10 = 4.2-6.9) but decreases again to a centennially cycling fraction (Q10 = 2.4-2.8) in boreal forest soil. Compared to the method used for current global estimates (temperature sensitivity of all SOC equal to that of the total heterotrophic soil respiration), the soils studied will lose 30-45% more carbon in response to climate warming during the next few decades, if there is no change in carbon input.” Already now the carbon dioxide emissions from soil are ten times higher than the emissions of fossil carbon. A Finnish research group has proved that the present standard measurements underestimate the effect of climate warming on emissions from the soil.” So much doubt about only one claim from this post ...
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  35. "That which can be asserted without evidence, can be dismissed without evidence." - Christopher Hitchens I think that applies here.
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  36. 34 Arkadiusz, 1) Your scenario is impossible unless the biosphere sink somehow distinguishes natural CO2 and anthropogenic CO2. 2) It appears the hypothesis mentioned there is that human had an impact on the carbon cycle long before the burning of fossil fuel through land use changes. I am not surprised that it is not well constrained, and I fail to see how the fact that the anthropogenic impact 1000's years ago has anything to do with the present warming which began 100 years ago. 3) Regarding those two soil studies, the take home message is that the human impact on the CO2 cycle maybe worse than previously thought, not that human is not contributing significantly to global warming.
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  37. Arkadiusz - the first paper you cite is talking about human climate effects thousands of years ago. The second paper is talking about soil carbon emissions as a feedback. There is no question that recent CO2 increases are due to human activities. To be blunt, the "doubt" about which you speak is limited to your own confusion about the subject.
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  38. @IanC I fail to see how anthropogenic emissions are going to do anything when they are well below historical averages of atmospheric co2. Additionally, I fail to see how there are going to be climate catastrophes with a GAT of 12C versus the GAT of the past 600 million years, which is 22C. Please explain yourself.
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    Moderator Response: Peruse the Arguments list, where among the many relevant posts you will find "It's Not Bad." You can also type It's Not Bad into the Search field at the top left of this page. Also "It's Not Urgent," "CO2 Is Not a Pollutant," "CO2 Was Higher in the Past," and "CO2 Was Higher in the Late Ordovician."
  39. Cadbury @ post that might not be deleted... You merely need to look at the radiative forcing related to enhanced GHG concentrations and you will clearly see why they are going to do something. If you are under the assumption that we can take the planet where we currently exist, have evolved, have developed agriculture and large complex human society... take that and raise the global temperature back to where it was 65 mya and actually survive... then you are clearly a denier of the first order.
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  40. Well I will say this website is far more fair and honest than realclimate or ( -snip- ). @Rob It is a possibility that we cannot return to the GAT of 65 mya but I argue that since humans are the most adaptable species ever to exist, and since animals were present 65 mya, we can survive in this type of climate. My problem with your argument is that there just isn't anyway to test it. In my opinion, the only way to test such a hypothesis would be to find a planet similar to earth's, with people on that has a co2 concentration of 560ppm. Of course it is a fool's dream so we have to use models. And I'm not saying that this is bad and models shouldn't be used, only that models are only models.
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    Moderator Response: You must comment on the appropriate threads. See my moderator response on your previous comment, for instructions on how to find those. Regarding models, see "Models Are Unreliable." Further off-topic comments will be deleted from this thread.
  41. Cadbury... I'm moving the conversation over to CO2 was higher in the past where you can read a response to your comment here.
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  42. I found the article really useful, so this comment is about just one point in the article The article describes the statement "CO2 is less than a mere four 100ths of 1% [of the atmosphere]" as an error (one of the "three principle errors" - "principal" by the way). The problem with Thompson's statement is not that it's erroneous (it's equivalent to saying 400ppm if my arithmetic is correct), but that it's being misleadingly used to support an erroneous case. The error is in the inference and the remaining two statements. I am happy with the following paragraph in this article - a small quantity can have a big effect - which shows why the statement in question is being misleadingly used. I think that simply saying it's an error leaves the article open to valid criticism. Of course the word "mere" in Thompson's statement is pejorative, but could be turned around to advantage. Although the quantity of CO2 is a "mere four 100ths of 1%" of the atmosphere, we already know that a mere three 100ths of 1% is enough to stop the earth turning into a snowball.
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  43. @#IanC “... the biosphere sink somehow distinguishes natural CO2 and anthropogenic CO2.” This is true. But how would "impossible" my scenario? There is no chemical difference (14C/13C/12C) between the old carbon from fossil fuels, the old soil, ventilation of the deep ocean. Thus, if the current warming is unprecedented in the Holocene, unprecedentedly rapid respiration it must be used not only from present NPP - but with the old carbon stocks and ... can not be in balance with the sink - type of biosphere. Decomposition of old organic matter as a result of deeper active layers in a snow depth manipulation experiment, Nowiński et al., 2010.: “Our results indicate that, as permafrost in tussock tundra ecosystems of arctic Alaska thaws, carbon buried up to several thousands of years ago will become an active component of the carbon cycle, potentially accelerating the rise of CO 2 in the atmosphere.” “Radiocarbon ages of heterotrophically respired C ranged from <50 to 235 years BP in July mineral soil samples and from 1,525 to 8,300 years BP [!] in August samples ...” Carbon respiration from subsurface peat accelerated by climate warming in the subarctic, Dorrepaal et al., 2009.: “Climate warming therefore accelerates respiration of the extensive, subsurface carbon reservoirs in peatlands to a much larger extent than was previously thought ...” “Assuming that our data from a single site are indicative of the direct response to warming of northern peatland soils on a global scale, we estimate that climate warming of about 1°C over the next few decades could induce a global increase in heterotrophic respiration of 38–100 megatonnes of C per year. Our findings suggest a large, long-lasting, positive feedback of carbon stored in northern peatlands to the global climate system.” In the past, the main sink for the large surpluses of CO2 has always been a terrestrial biosphere - higher plants - tissue. Organisms tissue always respond (longer process of reproduction) of delay in relation to a unicellular soil bacteria (respiration) or CO2 from the deep ocean ventilation. Hence - L-V model is - for source and sink - especially photosynthesis - the most reasonable. This confirms this paper: Loss of Carbon from the Deep Sea Since the Last Glacial Maximum, Yu et al., 2010. : “Combined benthic δ13C and [CO3 2-] results indicate that deep-sea-released CO2 during the early deglacial period (17.5 to 14.5 thousand years ago) was preferentially stored in the atmosphere, whereas during the late deglacial period (14 to 10 thousand years ago), besides contributing to the contemporary atmospheric CO2 rise, a substantial portion of CO2 released from oceans was absorbed by the terrestrial biosphere.” Only after three thousand. years the biosphere has removed the natural surplus of the early Holocene ... Theory o 100% of the anthropogenic origin of the unbalanced excess CO2 in atmosphere - affect the basics of ecosystem sciences - population dynamics.
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  44. @dana1981 Cited paper mainly says that there is a problem with the carbon balance for the Holocene - the CO2 from the soil (not only the influence of ancient civilizations agricultural): “However, there are uncertainties in our current study, which provides the guidance for future studies of peatlands and Holocene carbon cycle dynamics. The uncertainties related to our model simulations are mainly caused by the terrestrial vegetation ...” A well, there is a sentence: “However, these uncertainties are not critical to the interpretation of our results, as the overall magnitude of NP carbon uptake is large.” But there are doubts (perhaps the errors - and certainly "not critical"?) - but certainly they are not my mistakes. And 0.5 ppm of CO 2 per year - participate in the unbalanced excess atmospheric CO2 - not a hypothetical value. There are analysis indicating the decisive contribution of natural CO2 Spencer. Spencer only speculate where it is a natural surplus of CO2. Sources shows study a case of Mt. Pinatubo and El Nino in 1997/8. Volcanoes - in total - so far the negative impact on global NPP - ”many years after the eruption”. The same is confirmed - says in this work: Aerosols and the land carbon sink, Angert & Krakauer, 2010. in connection with (contra) to work: Impact of changes in diffuse radiation on the global land carbon Mercado, et al., 2009. The resulting conclusions are most interesting in this paper: Impacts of large-scale climatic disturbances on the terrestrial carbon cycle, Erbrecht & Lucht, 2006. Every sentence is extremely important here: “The amount of carbon dioxide in the atmosphere steadily increases as a consequence of anthropogenic emissions but with large interannual variability caused by the terrestrial biosphere.[...]” “The response of soil respiration to changes in temperature and precipitation explains most of the modelled anomalous CO 2 flux.” “We therefore conclude that during the last 25 years the two largest disturbances of the global carbon cycle were strongly controlled by soil processes rather then the response of vegetation to these large-scale climatic events.” “Atmospheric carbon dioxide measurements show that the rate of increase of atmospheric CO2 varies substantially from year to year ...” “It is widely accepted that these variations are caused by the terrestrial biosphere through the processes of carbon uptake during photosynthesis and carbon release during soil respiration ...” Mt. Pinatubo: “In comparison, variations in the oceans [Two decades of ocean CO 2 sink and variability, Quéré et al., 2003.], deforestation, and land use change are much smaller ...” “Results show that a large fraction of the observed CO 2 growth rate variability is controlled by varying soil organic matter decomposition rather than changing plant productivity [...].
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  45. ... and on Commentary on the RealClimate from 2004 shows how currently is growing rapidly science.
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    Moderator Response: [DB] I'm sorry, Arkadiusz, I don't understand this one. Is this an extension of your previous comment? It is incomplete as it stands now.
  46. Arkadiusz, If I am understanding you correctly, your scenario is: 2ppm natural imbalance, 8ppm anthropogenic CO2 7.5ppm additional biosphere sink Your conclusion is that the net 2.5ppm increase is due to 2ppm natural imbalance and 0.5 anthropogenic CO2 which is impossible unless the sink differentiates the source of CO2. It should be 2ppm due to anthropogenic and 0.5 due to natural imbalance. Your scenario also misses a key piece of information. We know that only 50% of the CO2 we generate is going into the atmosphere, so the net natural sink (bio sink - imbalance) equals 4ppm in your scenario. The rest of the papers you cited stress that there are potential for amplification of the effects of anthropogenic CO2, and I am not sure how they help your point.
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  47. JulianRGP #42 - thanks, and good point. I revised the text accordingly.
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  48. There was a hearing several months ago in congress, the first group consisted of Lindzen, Cicerone, Cullen and several others I cannot recall. Heidi Cullen at one point claimed that some flood was a 1 in a 1000 year event or something, I would hope we can all agree it was a preposterous claim. She also gave the highest IPCC estimate for warming that they predict, which I thought was misleading.
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    Moderator Response: [Dikran Marsupial] There is nothing preposterous about the claim at all per se; there is a well established field of statistics called "extreme value theory" that is the basis for statements of exactly that form. There is an excellent book on the subject by Stuart Coles, see page 49 in particular, the one in 1000 year figure is what is known as the "return period".
  49. Well because its in a 3hr video and it would be hard to go through the whole thing to find the exact spot. I shall attempt though.
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  50. Cadbury #48:
    "Heidi Cullen at one point claimed that some flood was a 1 in a 1000 year event or something, I would hope we can all agree it was a preposterous claim."
    It's entirely common to label a particular weather event as 1 in 100 year, 1 in 500 year, etc. The 2010 Tennessee floods were 1 in 1,000 year event, for example. So unless you provide evidence that Cullen's statement was wrong, no, I don't agree it was a preposterous claim. Especially if she was referring to the floods in Tennessee, in which case not only would her statement not be preposterous, it would be entirely correct.
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