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The discovery of fire: initial steps toward anthropogenic climate change

The evidence for a rapid shift in state of the terrestrial atmosphere-ocean system over the last two centuries (see figure 1) requires a deep time perspective, beyond events of the day. Tracing the original…

Humanity’s control of fire has led to a vastly changed atmosphere. Jason A Samfield

The evidence for a rapid shift in state of the terrestrial atmosphere-ocean system over the last two centuries (see figure 1) requires a deep time perspective, beyond events of the day. Tracing the original blueprints of anthropogenic effects on the terrestrial environments takes us back at least a million years to the time when - according to research released this month - the first compelling evidence for human use of fire was found.

Of all life forms which ever existed, only the genus Homo acquired the skill of igniting and transporting fire. This gave Homo not only warmth, cooking and protection from animals, but a high degree of power over nature. Prehistoric hominids burned large parts of the biosphere and, more recently, combusted carbon and hydrocarbons derived from fossil biospheres up to 400 million years old.

The high intelligence underlying human inventions has been variously attributed to a large brain size (Chimpanzees ~395 grams; Australopithecus apheresis ~430 grams; Homo ergaster ~850 gram; Homo sapiens ~1350 grams) and a high brain/body mass ratio (~1/40).

However, sperm whales brains weigh ~8000 grams and elephant brains over 5000 grams. Mice have a brain/body mass ratio similar to that of humans (1/40) and small birds a higher brain/body mass ratio (1/12). A more confident parameter of human intelligence is the high ratio of the neocortex (frontal intelligence lobe) to medulla (lower “mammalian” part of the brain stem) in the human brain (Lemurs ~10; monkeys and apes 20-50; humans 105).

Theories which try to explain the uniqueness of humans invoke its bipedal nature, language and the use of stone and bone tools. In these respects, however, pre-Homo sapiens hominids were hardly unique. Many animals are bipedal and some use tools. Termites design articulate nests, insects have a sophisticated language (such as the bee’s dance), meerkats make special calls, whales and dolphins echo-locate and birds have navigation systems.

However, Homo’s ability to ignite fire constitutes an exclusive blueprint not shared by any other life form, with far-reaching consequences. This facility was allowed by the potentially flammable terrestrial environment where hominids emerged, inhabiting plant-rich land surfaces surrounded by phytoplankton-rich oceans where photosynthesis produces an oxygen-rich atmosphere and plant decay results in formation of carbon-rich surface deposits and derived peat and coal deposits.

The evolution of land plants in the late Silurian (~420 Ma: vascular plants such as Cooksonia and Baragwanathia) and in the Permian (299–251 Ma: Cycads and Ginkgo) led to the accumulation of carbon as cellulose in trees and grasses, soils and bogs, methane hydrate and methane clathrate.

During tropical greenhouse gas-dominated eras (Silurian-Carboniferous - 443–299 Ma; early Mesozoic - 251–65 Ma) there were extensive fires from lightning, volcanic eruptions and underground peat fires. Diagnostic optical refractive indices allow scientists to estimate fire frequency (see figure 2) from charcoal remains. In the Permian atmospheric oxygen exceeded 30%, a level at which even moist vegetation becomes flammable, as represented in charcoal concentrations as high as 70% in coal.

When humans harnessed fire, it elevated the species’ oxygenating capacity by many orders of magnitude as we utilized the solar energy stored in plants. As the use of fire, and subsequently of combustion, have grown, this increased planetary entropy (in physics - a measure of the degree of disorder and chaos of a system) to levels approaching those triggered by the geological events, including those resulting in the major mass extinctions in geological history. The splitting of the atom achieves yet higher levels of entropy.

Likely the mastery of fire has been driven by necessity. There were abrupt environmental shifts when mean global temperatures varied during glacial-interglacial shifts by about ~5°C and local temperatures by larger amounts. Humans had to find refuge in relatively protected sub-tropical shelters, such as the East African rift valleys.

Early Paleolithic evidence for human-lit fires includes hearths containing charcoal, burnt bones and red clay shards heated to 400°C and higher temperatures. Widespread use of fire in the late Paleolithic is indicated by charred logs, charcoal, reddened areas, carbonised grass stems and plants and wooden implements hardened by fire.

A likely advantage of cooking was the enhanced supply of protein, allowing an increase in brain size (Homo ergaster ~850 grams; Homo sapiens ~1350 grams). Over hundreds of thousands of years, gathered during long nights around camp fires, captivated by the flickering life-like dance of the flames, humans developed curiosity, imagination, insights, cravings, fears, premonition, legends, aspiration for immortality and beliefs in deities and gods. Oldest expressions of cultural and spiritual creative minds may date back to 350,000 years ago, although this remains unconfirmed.

As climate conditions stabilized in the early Holocene, around 8000 years ago, agriculture and production of excess food allowed these ideas to be manifested through both the creative and destructive activities of civilizations.

The stabilisation of climate allowed cultivation of crops, enhanced by smelting of metals and crafting of ploughs. Extensive burning and land clearing associated with agriculture, from about 10,000 years ago, culminated with the combustion of fossil fuels.

Bill Ruddiman suggests the rise in CO₂ in the mid-Holocene reflects land clearing, fires and agriculture, defining the onset of an Anthropocene era. He wrote, “A wide array of archaeological, cultural, historical and geologic evidence points to viable explanations tied to anthropogenic changes resulting from early agriculture in Eurasia, including the start of forest clearance by 8000 years ago and of rice irrigation by 5000 years ago.”.

However, other authors define the onset of the Anthropocene at the dawn of the industrial age in the 18th century. They attribute the mid-Holocene rise of greenhouse gases to natural perturbations during the interglacials, for example the 420-405 thousand year old Holsteinian interglacial. According to this definition the Anthropocene is characterized by greenhouse gas emissions levels exceeding those of any earlier geological period (see Figure 3).

Since the 18th century, burning fossil fuels and clearing land increased atmospheric carbon content by 237 billion ton carbon (GtC). The present atmospheric carbon concentration is 820 GtC at present, an increase of some ~39% relative to the original level of 590 GtC. Of the additional CO₂, approximately 42% stays in the atmosphere which, together with other greenhouse gases, led to an increase in the atmospheric energy level of ~+3.2 Watt/m2 and of potential mean global temperature by +2.3 degrees Celsius (see figure 1). Approximately -1.6 Watt/m2, equivalent to -1.1°Celsius, is masked by industrially emitted sulphur aerosols. For more on this, see earlier articles in The Conversation.

The significance of human mastery of fire in terms of the consequences of enhanced entropy has been underestimated. Human respiration dissipates two to ten calories/minute. A camp fire releases more than 100,000 calories/minute, but the output of a 1000 megawatt/hour power plant expends more than 2 billion calories/minute and nuclear fission orders of magnitude higher. This amounts to an increase in entropy on the scale of geological events.

While complexity increases in conurbations, the rise in atmospheric energy and heat due to the release of greenhouse gases associated with exothermic combustion results in a series of extreme weather events (http://www.ipcc-wg2.gov/SREX/), droughts, floods and storms, degrading natural habitats.

According to Ancient Greek mythology, fire was stolen from the gods by the titan Prometheus, who breathed it into human clay figures. From our modern perspective, this legend and related stories in other traditions acquire a special meaning.

For an intelligent species to be able to explore the solar system planets but fail to protect its own home planet defies explanation. For a biological species to magnify its entropic effect on nature by orders of magnitude, developing cerebral powers which allow it to become the intelligent eyes through which the Universe explores itself, hints at yet unknown natural laws which underlie life, consciousness and complexity.

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  1. David Arthur

    resistance gnome

    Thanks for this, Prof Glikson.

    The causative link between hominid evolution and fire is well-expressed in setting out some advantages of cooking: "... the enhanced supply of protein, allowing an increase in brain size (Homo ergaster ~850 grams; Homo sapiens ~1350 grams)".

    You then go on to link this with the emergence of religious belief: "Over hundreds of thousands of years, gathered during long nights around camp fires, captivated by the flickering life-like dance of the flames, humans developed curiosity, imagination, insights, cravings, fears, premonition, legends, aspiration for immortality and beliefs in deities and gods."

    Ironic, then, that the product of this evolution, the Religious Right, are among the most ardent Deniers of climate change.

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    1. James Doogue

      logged in via email @doogue.net

      In reply to David Arthur

      " the Religious Right, are among the most ardent Deniers of climate change."

      Really?

      In any event, I actually do not know of one single person who denies climate change. Perhaps you can tell us who does?

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    2. David Arthur

      resistance gnome

      In reply to James Doogue

      Thanks James. Cardinal George Pell is the Archbishop of the Catholic Archdiocese of Sydney.

      He delivered the 2011 Global Warming Policy Foundation Annual Lecture at Westminster Cathedral Hall, London, on 26 October 2011. A transcript iof this lecture "Can Our Babel Succeed? Questioning the Moral Dimension of Climate Change" is available at http://www.abc.net.au/religion/articles/2011/11/09/3360589.htm.

      This attracted responses from religious adherents and non-believers alike.
      For example…

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    3. James Doogue

      logged in via email @doogue.net

      In reply to David Arthur

      Thanks David, I still can't find anyone who denies that the climate changes. I know I am being pedantic, but if someone is being accused of being a 'Climate Change Denier', I expect that to mean they do not accept that the climate changes. I do not know anyone in that category.

      Sure there is plenty of disagreement about the various causes of climate change . Even the RealClimate amigos admit to some disagreements in private.

      Unfortunately there are plenty of illogical nutters on both sides…

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    4. David Arthur

      resistance gnome

      In reply to James Doogue

      Thanks James. You mention errors and controversies following IPCC AR4 (2007). In that case, you may be relieved to know that the physical scientists of Working Group 1 (WG1) were found to have made no mistakes.

      Any and all errors were in the assessments of Working Groups 2 and 3, the "social scientists" concerned with adaptation, mitigation and economics. For example, WG1 carrectly reflected the then-understood expectation that Himalayan glaciers are not likely to disappear before 2350; the 2035 furphy was in WG2.

      Elsewhere on this page, I believe I've explained the mechanism of the greenhouse effect to you (look for the section beginning "Earth is warmed by absorbtion ..."). It's pretty well correct, and sets out how and why climate is beyond doubt. What we should be doing is deciding what to do about it, so that religious and political leaders who continue to dispute the reality of these phenomena are condemned by their own words.

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  2. James Doogue

    logged in via email @doogue.net

    According to the 582-page report here: http://www.ipcc-wg2.gov/SREX/ The basic conclusions of the Intergovernmental Panel on Climate Change’s (IPCC) on the subject of extreme weather are:

    “While there is evidence that increases in greenhouse gases have likely caused changes in some types of extremes, there is no simple answer to the question of whether the climate, in general, has become more or less extreme.”

    “There is medium evidence and high agreement that long-term trends in normalized…

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    1. Andrew Glikson

      Earth and paleo-climate scientist at Australian National University

      In reply to James Doogue

      James Doogue,

      1. Since you looked at the IPCC http://www.ipcc-wg2.gov/SREX/ you would have also noticed statements such as:

      "The IPCC-2011-AR5 report projecting extreme weather events states: "Models project substantial warming in temperature extremes by the end of the 21st century. It is virtually certain that increases in the frequency and magnitude of warm daily temperature extremes and decreases in cold extremes will occur in the 21st century on the global scale. It is very likely that…

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    2. Andrew Glikson

      Earth and paleo-climate scientist at Australian National University

      In reply to James Doogue

      P.S.

      For a comprehensive explanation of the effects of CO2, methane and Nitric oxide on the atmosphere refer to: http://pubs.giss.nasa.gov/abs/ha02210k.html

      Hansen et al. 2007
      Hansen, J., Mki. Sato, P. Kharecha, G. Russell, D.W. Lea, and M. Siddall, 2007: Climate change and trace gases. Phil. Trans. Royal. Soc. A, 365, 1925-1954, doi:10.1098/rsta.2007.2052.

      http://pubs.giss.nasa.gov/abs/ha02210k.html

      Paleoclimate data show that the Earth's climate is remarkably sensitive to global forcings…

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    3. David Arthur

      resistance gnome

      In reply to James Doogue

      Here's whay a doubling of atmospheric CO2 will give much more than 1.2 deg C warming:
      Increased CO2 → increased temperature → increased atmosphere capacity to hold water → increased water vapour in atmosphere→ increased greenhouse warming due to additional water.

      This is already happening. If 1.2 deg C warming was the only effect of doubling atmospheric CO2, then we'd expect a warming of 0.45 deg C over the last century, in which time atmospheric CO2 has increased from ~300 ppm to 390 ppm due to logarithmic dependency.

      In fact, warming of 0.8 deg C is observed to date, plus much larger heat absorbtion in ocean (not much observed T rise, but observed thermal expansion plus observed polar ice melting).

      Inferences of only 0.06 deg C warming from satellite measurements are erroneous.

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    4. Andrew Glikson

      Earth and paleo-climate scientist at Australian National University

      In reply to David Arthur

      David,

      1. Measured mean global temprature rise in the range of 0.8 - 0.9C does not take account of the tansient masking effect of sulphur aerosols (residence time ~ 1-2 years). As a corollary, when the body temperature of a patient who initially suffers from ~40C is reduced by Panadol to ~37C, it is still not possible to say the patient is cured from a ~40C state, unless treated with antibiotics.

      2. A distinction needs to be made between fast climate feedbacks and sensitivity (due to changes…

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    5. Philip Dowling

      IT teacher

      In reply to Andrew Glikson

      For me the problem with the peer reviewed literature is not the datasets that are used but the conclusions that are reached.
      Astronauts and engineers are surely trained in the use of logic.
      Unless people believe that there is a climate change logic, then they have the tools to analyse claims from people with a variety of specialities.
      I find it passing strange that the prognostications of economists such as Ross Garnaut and Lord Stern are accorded such respect when it comes to climate change, when neither predicted the GFC despite it being in their field of specialty.
      The use of extrapolation and probability by climate change scientists is voodoo science. Predicting the future has been attempted by diviners, astrologers, soothsayers, numerologists, and priests. Climate change scientists follow in this noble tradition but using tools that are no more reliable.

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    6. James Doogue

      logged in via email @doogue.net

      In reply to David Arthur

      The 1.2C calculated maximum warming from a doubling of CO2 assumes a ‘no feedback’ theoretical model which is used by the IPCC.

      Judith Curry provides a good discussion on the IPCC’s (TAR), accepted temperature increase based on the ‘no feedback’ position, and also puts a strong case that even that theoretical estimate may be overestimated: Read here: http://judithcurry.com/2010/12/11/co2-no-feedback-sensitivity/

      What you have done is exactly what I am complaining about, that is to add unproven…

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    7. James Doogue

      logged in via email @doogue.net

      In reply to Andrew Glikson

      Andrew Glikson, responses using your numbering system:

      1. As soon as you quote from the IPCC "Models project...." you make my point. Models are not empirical data, and have been poor predictors. When pressed even the IPCC have to admit this. See my response to David Arthur below for further information.

      2. I am not arguing about the GHG effect! It's funny that most alarmists think that sceptics who do not accept increasing CO2 emissions will lead to catastrophic Climate Change, are arguing…

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    8. James Doogue

      logged in via email @doogue.net

      In reply to Andrew Glikson

      I am familiar with the effects of methane and nitric oxide and I am afraid I am not a fan of Hansen. He has proven to me at least he is more activist than scientist and this taints his work. Sure he gets published by his admiring followers, but then in the climate science area there is a sad history of papers getting published which shouldn't have been.

      The methane eating bacteria blooms following the Deepwater Horizon oil spill was a demonstration that scientists predicting an ecological disaster…

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    9. David Arthur

      resistance gnome

      In reply to James Doogue

      Thanks James, excellent discussion, except that water vapour is not clouds - clouds are composed of condensed (liquid) water.

      Here's a summary of what's known.

      Earth is warmed by absorbtion of short wave sunlight. Because of this, Earth's temperature can remain unchanged by returning the same amount of energy to space. That is, solar shortwave energy is balanced by the earth re-radiating to space as a 'black body' radiator with a characteristic temperature of ~255K; that is, from space…

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    10. David Arthur

      resistance gnome

      In reply to Philip Dowling

      Thanks Philip. What do you mean by "a climate change logic"?

      My (non-IT) understanding is that there is only one form of logic applicable to the physical world.

      If earth's climate is influenced by atmospheric greenhouse gases, then variation in the amounts of atmospheric greenhouse gases will affect the climate.

      If climatic conditions affect the emission or absorbtion of greenhouse gases at the earth's surface, then there is a feedback.

      Solubility of CO2 in sea water varies with…

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    11. David Arthur

      resistance gnome

      In reply to James Doogue

      Warming "feedbacks" already initiated (ie tipping points already being crossed) are loss of Arctic sea ice, so that boreal summer sunlight absorbtion in the Arctic Ocean is increasing (less sunlight reflection), sublimation of offshore Siberian methane clathrates, and methane outgassing from thawing permafrost.

      To my knowledge, cooling "feedbacks" are as yet not well defined, let alone characterised.

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    12. David Arthur

      resistance gnome

      In reply to James Doogue

      James writes: "... what needs to be recognised is that we know nowhere near enough to be making predictions ..."

      I point out that it is in the making of predictions, then comparing these predictions with subsequent observations that we learn.

      James adds: " ... and taking actions which could have unintended negative consequences."

      I point out that among the actions which are extremely likely to have unintended adverse consequences are the recycling of geosequestered ("fossil") carbon to the atmosphere.

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    13. David Arthur

      resistance gnome

      In reply to Andrew Glikson

      Thanks Andrew. Studies of the Pliocene suggest that present climate conditions may well be a long way from the "equilibrium" of radiative balance.

      I understand the Pliocene Epoch ended as the Isthmus of Panama formed, isolating Atlantic and Pacific Oceans, the extent of Greenland glaciation increased substantially immediately thereafter, and large-scale boreal glaciation soon followed.

      The presence of the Isthmus of Panama is probably the major cause of any difference between Pliocene climate and whatever an "equilibrium" Anthropocene climate might be.

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    14. James Doogue

      logged in via email @doogue.net

      In reply to David Arthur

      Sorry David, that was sloppy of me, I meant 'accurate' predictions. As we have seen time and again, the alarmist predictions made have not matched empirical evidence. But the point is the IPCC and many alarmists simply gloss over all the really important climate forcing factors and feedback mechanisms and talk as if the 'science is settled'.

      I have never intuitively supported 'carbon capture'. Not that I am convinced CO2 is a problem, but it seems to me that trying to capture CO2 underground and expecting it to stay there given geological movements and variability is the definition of overly optimistic.

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    15. David Arthur

      resistance gnome

      In reply to James Doogue

      While we can be certain that increasing atmospheric temperatures will increase water vapour content and hence greenhouse warming, we cannot be certain that this implies an increase in the prevalence of condensed phase water (clouds). This is because clouds turn into rain which returns to earth.

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    16. David Arthur

      resistance gnome

      In reply to James Doogue

      It seems to me that the majority of "alarmist" predictions are the result of journalists looking for and generating *good* copy.

      I'm glad you mention carbon capture (I didn't). I agree with you that it's pretty much a waste of scarce taxpayer funds - I note that no coal-mining company stumped up for R&D into the only possible technology that might ensure continued use of coal. That tells me that the hard-nosed assessment is that CCS is nought but a boondoggle.

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  3. Ian Donald Lowe

    Seeker of Truth

    "Bill Ruddiman suggests the rise in CO₂ in the mid-Holocene reflects land clearing, fires and agriculture, defining the onset of an Anthropocene era. He wrote, “A wide array of archaeological, cultural, historical and geologic evidence points to viable explanations tied to anthropogenic changes resulting from early agriculture in Eurasia, including the start of forest clearance by 8000 years ago and of rice irrigation by 5000 years ago.”."

    With all due respect, this is foolishnes in the extreme…

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    1. David Arthur

      resistance gnome

      In reply to Ian Donald Lowe

      Humans learnt to harness fire, and thereafter its prevalence must have increased; fire regimes would have replaced sporadic wild fires - individually much less damaging, but collectively much greater in extent.

      Relatively small groups of humans can and do change landscapes; I suggest you read Bill Gammage's "The Largest Estate On Earth".

      There may have been relatively few humans around 8000 years ago, but when some of those humans set about large-scale methanogenesis, they would have started to influence the climate.

      There may have been relatively few humans in Genghis Khan's army, but their efforts to facilitate reafforestation across large swathes of Eurasia may, along with Yersinia Pestis, have exacerbated the subsequent Little Ice Age. Similar considerations hold for the armies of the conquistadors.

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  4. Timothy Curtin

    Economic adviser

    James D - spot on when you say "...today's news release [on the letter to the head of NASA] from ex NASA Scientists, Astronauts and Administrators to know there is no scientific consensus as claimed by the Greens, Labor and most of the contributors here at The Conversation", especially when Glikson said "For an intelligent species to be able to explore the solar system planets but fail to protect its own home planet defies explanation".

    Really? Yet the target of the NASA astronauts' et al letter was none other than James Hansen of NASA-GISS who made no contribution whatsoever to space exploration, mainly because manifestly like Pooh he is a bear of very little brain so was sent off to do weather instead.

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    1. Yoron Hamber

      Thinking

      In reply to Timothy Curtin

      As you speak of Hansen :)

      There's such a lot of BS about him on the internet, some of them downright lies as him predicting scenarios that never happened like " James Hansen erroneously predicted the West Side Highway would be underwater by 2008." http://www.skepticalscience.com/Examining-Hansens-prediction-about-the-West-Side-Highway.html

      RealClimate has a guest commentary from Geert Jan van Oldenborgh and Rein Haarsma, KNMI lookking over one of the first climate predictions Hansen et al (1981) made.

      It's still surprisingly correct. http://www.realclimate.org/index.php/archives/2012/04/evaluating-a-1981-temperature-projection/

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  5. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    "Every one is entitled to his opinions but not to his facts" (Daniel Moynihan).

    It all depends on one's source of information, i.e. whether it is from:

    A. The bulk of the peer reviewed literature in scientific journals, the Worlds acadmies of science (including the AAS), NSIDC (National Snow and Ice Data Centre), Hadley-Met, NOAA, NASA, Potsdam Climate Impacts institute, CSIRO, BOM, the comprehensive summamries of peer review litarture by the IPCC and so on.

    or

    B. Opinion on blogs…

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  6. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    P.S. My apoloogies for the typos

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  7. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    David,

    The closing of the isthmus of Panama is dated at about 4 Ma whereas the end of the Pliocene is defined at 2.8 Ma. Comparisons need to be made between the end Pliocoene (~4 - 2.8 Ma) and the present. In both instances temperatures are higher than the Holocene by about 2 degrees, except that:

    1. At present about 1.1 degrees C are masked by sulphur aerosols
    2. A lag effect of ice melt and sea level rise pertains. Namely.late-Pliocene-like radiative forcing of ~400 ppm CO2 are reached by current 394.8 ppm CO2, but ice melt and sea level rise lag behind.

    However, the rapid current rate of CO2 rise - at >2 ppm/year - is in sharp distinction from Pliocene climate change rates - with potentially serious consequences in terms of destabilization of the cryosphere and release of methane.

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    1. David Arthur

      resistance gnome

      In reply to Andrew Glikson

      Gday Andrew, thanks for clarifying my confusion on dates.

      Given the ~1.2 million year period between formation of the Isthmus of Panama and the onset of Pleistocene glaciation, is it reasonable to propose the former as having a bearing on the latter?

      I'm not sure that 'masking' is the correct term to use to describe sunlight reflection from aerosols; the presence of the aerosols has certainly prevented penetration of the atmosphere by a fair amount of solar radiation (solar 'dimming'), so perhaps…

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    2. Andrew Glikson

      Earth and paleo-climate scientist at Australian National University

      In reply to David Arthur

      David,

      The closure of the Panama Isthmus isolated the Pacific Gyre from the Atlantic Gyre, resulting in marked enhancement of the cross-latitudinal circulation in both the Pacific and Atlantic oceans, including the Gulf Stream, Humboldt and California currents, transporting heat to high latitudes and, conversely, cold water to subtropical oceans.

      For this reason comparisons between the present ocean regime and the Pliocene needs to be made with post-4 Ma regime, i.e. in view of this fundamental geotectonic change.

      Heating of the troposphere due to enhanced insolation occurs much faster than transfer of heat to the ocean. Reduced aerosol levels results in fast rise in solar radiation reaching the ground, as for example occurred when jet traffic ceased over large parts of the US post-9/11.

      For detailed consideration of the terrestrial heat budget, including atmosphere-ocean heat transfer, I can send you relevant papers if you send me an e-mail at andrew.glikson@anu.edu.au

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  8. Timothy Curtin

    Economic adviser

    Andrew Glikson: What you call the "bulk of the peer reviewed literature" is actually very thin, because the bulk is in fact repetitively produced by relatively few individuals who pal review or co-author with each other on a roster, e.g. my (Kevin T) turn to be "anonymous" pal reviewer, or my (KT) turn to be the lead author (Kev is actually the organiser of the roster, and editors who get in his way tend to get moved on).

    Thus Andrew cites the AAS's Q&A as if it was independent confirmation…

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    1. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin, the reason Lambeck et al were unable to discern an accelerating trend in sea level rise in the period 1950-2000 is because it was too small to be detected.

      Luckily for us, however, the accelerating trend has become unambiguously detectable over the last decade.

      I can't hope to match the rest of your sophistry.

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    2. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin argues that "climate science is produced by a rather small but closely inter-linked cabal of state-funded mercenaries".

      I refer him to Spencer Weart's bibliography for his book, "The Discovery of Global Warming". Conveniently, Weart has recast his book as a set of hyperlinked essays available at the website of the American Institute of Physics (http://www.aip.org/history/climate/index.htm).

      Weart's bibliography (http://www.aip.org/history/climate/bibdate.htm) lists 1742 references up until 2001 - thereafter, he suggests the reader refer to bibliographies for IPCC Working Group 1 (The Physical Basis of Climate Change) Assessments. Of these 1742 references, 1135 date from 1988 or earlier - that is, they predate the collapse of Soviet Communism.

      122 references predate Kevin Trenberth's 1944 birth in Christchurch, NZ.

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  9. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    REGARDING SEA LEVEL RISE

    In a recent article in The Australian titled “CSIRO alarmism more dangerous than CO2” (http://www.theaustralian.com.au/national-affairs/opinion/csiro-alarmism-more-dangerous-than-co2/comments-e6frgd0x-1226312898312), Ollier wrote “The CSIRO projection is extreme, but before explaining why, I would note that the world's main source of alarmism is the Intergovernmental Panel on Climate Change. This is not really a scientific body but one that adjusts data and subjects it…

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    1. Yoron Hamber

      Thinking

      In reply to Andrew Glikson

      Andrew, a pleasure reading you :)
      And peer reviewed articles are no joke.

      If you contract a carpenter you do well in checking his references, not doing so may give you cause for grief later as you stand in the fruit of his contributions :)

      I'm sure most guys and gals would agree to that?

      That's essentially what a peer review is. It's a way of checking up on the facts and see if they are what the contributor assumes them to be.

      But in the denial camp one can find the opposite. Questioning all peer reviews, and assuming that any blog able to manipulate some, often dubious, data, preferably short time as over , let's say? Eight years :) or maybe some decades naturally prove all other data wrong.

      So if I was working from that assumption I might have to assume that deniers and skeptics alike find good references unnecessary?

      Wouldn't like to be in that house when the gale come :)

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    2. Yoron Hamber

      Thinking

      In reply to Yoron Hamber

      Thinking of it. Interactions as when something do interact with something else. What do you think you can trace it back to?

      Momentum.

      simple, kinetic energy. So you have molecules and 'atoms' in the atmosphere interacting. When they 'interact' they give of an excess called radiation. That radiation can come in different Wavelengths/Frequencies, but the first and last the universe knows is 'heat'. That's what 'entropy' is all about.

      Heat.

      I don't know any other radiation that is as simple and self obvious :)
      Sh* you're Aussies, proud to use your own minds.

      Do it.

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  10. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    James,

    1. You state "we have seen time and again, the alarmist predictions made have not matched empirical evidence".

    The opposite is the case. To date, climate change projections have turned out to constitute underestimates, as in the following examples:

    A. Hansen et al.'s global temprature projections published in 1981 have been exceeded over the last 30 years by >0.1C http://blogs.crikey.com.au/rooted/2012/04/12/global-warming-projections-from-1981-prove-tellingly-accurate/

    B…

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  11. Timothy Curtin

    Economic adviser

    David Arthur commented:
    "Mr Curtin, the reason Lambeck et al were unable to discern an accelerating trend in sea level rise in the period 1950-2000 is because it was too small to be detected. Luckily for us, however, the accelerating trend has become unambiguously detectable over the last decade. I can't hope to match the rest of your sophistry."

    But you just did better than that: in fact the Church-White database at CSIRO as used in their 2011 paper shows a totally statistically insignificant increase in changes in sea-levels from 2000-09 (adj R2= MINUS 0.038, t= 0.55, p = 0.59). On the trend line itself the quadratic has a better fit than the linear and is actually negative.

    Could you kindly share your fits and statistical significance tests with the rest of us? Thanks.

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    1. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      A short enough series is not of great statistical significance.

      How does the 1950-2009 series look?

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  12. Timothy Curtin

    Economic adviser

    Now Arthur says "A short enough series is not of great statistical significance. How does the 1950-2009 series look?" yet only today he said "the reason Lambeck et al were unable to discern an accelerating trend in sea level rise in the period 1950-2000 is because it was too small to be detected.Luckily for us, however, the accelerating trend has become unambiguously detectable over the last decade". But as I have reported here, my analysis of the CSIRO (Church-White) data shows that to be untrue

    If Arthur could wean himself from his customary sophistry and do the actual statistical analysis I have done and reported here on the Church-White data set at CSIRO, he could (but never would) produce the longer term trends that he now claims would confirm his topsy-turvy view of the world.

    I have done what he suggests, showing even less acceleration of sea-level rise before 2000, but now prefer to see his own results before I comment again.

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    1. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Thanks Mr Curtin. Not having access to the data, I tend to rely on the peer-reviewed work.

      I refer you to Rignot et al, "Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise", Geophysical Research Letters v38 (2011).

      I repeat, as of 2004, Church and Lambeck state that they are unable to detect any ACCELERATION in the rate of sea level rise. This does not mean that the rate of sea level rise is 0; it is readily observed to be positive non-zero.

      Mr Curtin also argues that detection of different rates of sea level rise over the periods 1850-1950 and 1950-2000 is evidence of sophistry on the part of Church and Lambeck ("... but then the IPCC beckoned, and their tune changed ...").

      That is, Mr Curtin interpolates the literature to discern motives on the part of researchers. As shown here, his interpolation is not a "reading between the lines" so much as a "misreading between the lines".

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  13. Timothy Curtin

    Economic adviser

    Thank you David Arthur, but you do have access to the Church-White data at CSIRO in the same way as I do – just go CSIRO. As for the peer-reviewed [sick] work, Weart’s was not, and none of those waffling on about sea-level rise (e.g. Lambeck) let alone their pall reviewers actually knows how to derive rates of change of changes in sea-level, just as you don’t – and nor do Rigot & co in their 2011 GRL paper that you cited. Here is their conclusion: “Using the two-decade long MBM observation record…

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    1. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Thanks Mr Curtin.

      To help you out of your confusion, here's how I'd relate ice mass loss to sea level rise.

      Density of sea water = 1020 kg/m^3.
      Surface area of oceans = 361,543,000 km^2
      1 Gt ice = 1 x 10^12 kg.
      Therefore 1 Gt of melted terrestrial ice equates to

      (1 x 10^12 kg)/(1020 kg/m^3)/(361.543 x 10^12 m^2)

      = 0.00272 mm of sea level rise.

      0.00272 mm of sea level rise, in which case 475 Gt of ice melt would cause 1.292 mm of sea level rise.

      In their introduction, Rignot…

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    2. Timothy Curtin

      Economic adviser

      In reply to David Arthur

      DA, you have not responded to the challenges I posed for you in my previous. Your calculations are spurious, lacking any empirical support as is obvious, because you still refuse to provide LSR of your data on GMSLR relative to alleged rising GMT due to rising [CO2].

      That is no doubt because of your faith driven belief that the barely noticeable rise in GMT since 1958 (0.0125oC p.a.) is due to rising [CO2] of less than 2 ppmv since 1958.

      And that in turn is due to the self-proclaimed idiocy…

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    3. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Thanks Mr Curtin,

      No need for LSR to get first approximations, adequate for our level of discussion. I estimate sea level rise from terrestrial ice mass loss by

      volume = mass / density, then
      height = volume / area = (mass / density) / area

      V = M / R
      H = (M / R)/ A

      I estimate cumulative terrestrial ice mass loss after t years M(t) by

      M(t) = M(t=0) + L(t=0) x t + (1/2) x X(t=0) x t^2, where

      M(t=0) = cumulative terrestrial ice mass loss at year 0 (= 0, for our purposes)
      L(t=0…

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    4. Timothy Curtin

      Economic adviser

      In reply to David Arthur

      DA: Yes of course I meant less than 2 ppmv p.a. since 1958. Apologies.

      fyi: N2 and O2 ARE greenhouse gases precisely because they do not have absorbtion bands in the part of the electromagnetic spectrum in which earth dissipates radiation to space. If they could absorb they might radiate, but they do not, so cannot radiate, as Tyndall showed by physical experimentation, not by models.

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    5. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      With respect, Mr Curtin, you don't know what you're talking about. If N2 and O2 don't absorb, then they aren't specifically retarding dissipation of radiation.

      Perhaps you could read the Wikipedia entry on the greenhouse effect (http://en.wikipedia.org/wiki/Greenhouse_effect) ?

      BTW, that article includes the following: "The mechanism is named after the effect of solar radiation passing through glass and warming a greenhouse, but the way it retains heat is fundamentally different as a greenhouse works by reducing airflow, isolating the warm air inside the structure so that heat is not lost by convection."

      I should have been alerted to your lack of understanding when you asked if I had ever "... seen or been in a greenhouse?" I apologise for not previously identifying that non-cognisance.

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    6. Timothy Curtin

      Economic adviser

      In reply to David Arthur

      Arthur is wrong again when he says “if N2 and O2 don't absorb, then they aren't specifically retarding dissipation of radiation”, because if N2 and O2 do not absorb heat, they cannot radiate it to space or anywhere, as Tyndall showed, so they cannot and do not dissipate heat.

      The greenhouse works by its glass roof and walls preventing dissipation of heat by atmospheric CO2 and H2O, and the internal addition of CO2 then enhances the growth of the plants therein, which is why Dutch greenhouse operators pipe in CO2 provided by Shell from its North Sea gas and oil fields.

      As for Wiki, it is wrong if it claims as you say that greenhouses rely on solar radiation passing through their glass walls and roofs, as during winter in high latitudes they need internal heating. I know, I had one in York UK. Denied access to our central heating, nothing grew between from September to March.

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    7. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      N2 and O2 interact with thermal radiation via translational and rotational molecular modes, the same as ALL gas molecules. The distances between the energy levels of these modes are small enough, and the number of such modes large enough, as for this to represent a near-continuous nteraction spectrum (look up Kinetic Theory of Gases, in any Physical Chemistry textbook of the last century or so).

      CO2, CH4, H2O and other greenhouse gases ALSO have specific discrete chemical bond absorbtion modes…

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    8. Timothy Curtin

      Economic adviser

      In reply to David Arthur

      Arthur again evades the issue, which is whether or not N2 and O2 absorb and radiate heat. In the mad vocabulary of climate scientists they are not their so-called GHGs becuase they do not, but it is because they do not that they do not allow the earth's heat to escape to space.

      Again Arthur shows he does not understand why some places have greenhouses, by his comment that "Regarding greenhouses in York, wintertime sunlight intensity and duration at high latitudes is insufficient to maintain internal…

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    9. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin,

      Thanks for explaining that winter sunshine provides sufficient light for plant growth in York. I stand corrected on that point, and I note that you wrote: "As for Wiki, it is wrong if it claims as you say that greenhouses rely on solar radiation passing through their glass walls and roofs, as during winter in high latitudes they need internal heating". Greenhouses rely on solar radiation to provide the LIGHT for the green plants to grow; if they didn't have light, you'd only be growing…

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    10. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin correctly notes that Spencer Weart's "Discovery of Global Warming" is not peer-reviewed. This is because Dr Weart's book is educational, intended for the popular (lay) market.

      It is noteworthy that the American Institute of Physics supports the online edition, and the following information is contained under "Author/Credits".

      This text is by Spencer Weart, supported by the American Institute of Physics (Center for History of Physics). I developed the GCM essay from an essay by…

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    11. Mark Harrigan

      PhD Physicist

      In reply to Timothy Curtin

      Mr Curtin makes many claims denying the existence of global warming. His posts here show he should be ignored as an ignorant crank because he totally misunderstands what he is talking about.

      Mr Curtin claims that N2 and O2 do not absorb and radiate heat and that because of this they do not allow the earth's heat to escape.

      In making this ridiculous silly and false claim he demonstates just how little he understands of the basic physical processes.

      "Heat" does not "radiate". Only electromagnetic…

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  14. Andrew Glikson

    Earth and paleo-climate scientist at Australian National University

    THE ROLE OF ATMOSPHERIC N2 AND O2

    http://www.elmhurst.edu/~chm/vchembook/globalwarmA5.html

    "Certain gases in the atmosphere have the property of absorbing infrared radiation. Oxygen and nitrogen the major gases in the atmosphere, do not have this property. The infrared radiation strikes a molecule such as carbon dioxide and causes the bonds to bend and vibrate - this is called the absorption of IR energy. The molecule gains kinetic energy by this absorption of IR radiation. This extra kinetic…

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    1. Timothy Curtin

      Economic adviser

      In reply to Andrew Glikson

      Amazing to find myself in some agreement with Glikson, when he says "Certain gases in the atmosphere have the property of absorbing infrared radiation. Oxygen and nitrogen the major gases in the atmosphere, do not have this property." Exactly, only his source left out that unlike CO2, Nitrogen and Oxyegen not only do not absorb infrared radiation, they also for that very reason do not radiate ANY heat to space, as Harries et al have shown repeatedly (eg in Nature 2001) and that is why they are the…

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    2. Mark Harrigan

      PhD Physicist

      In reply to Timothy Curtin

      Wow - Mr Curtin shows on this thread and the state of the climate how little he understands

      https://theconversation.edu.au/state-of-the-climate-2012-5831

      He claims that CO2 is NOT a GHG because it can absorb (and re-radiate IR) but N2 and O2 ARE GHGs because they do NOT have the property of absorbing IR.

      One might as well claim that a window keeps light in because it is transparent and that a wall lets light through because it is opaque.

      A Greenhouse Gas - BY DEFINITION (look it up) is…

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  15. Timothy Curtin

    Economic adviser

    Arthur, see my just posted comment noting that even Andrew Glikson agrees with me that "Certain gases in the atmosphere have the property of absorbing infrared radiation. Oxygen and nitrogen the major gases in the atmosphere, do not have this property..."

    You are equally mistaken when you say "The issue regarding "greenhouse" GASES is that they selectively absorb more energy at particular wavelengths, further heating the planet". Except that as they RADIATE most of the heat they absorb, unlike the REAL GHGs, Nitrogen and Oxygen, they actually cool the planet (as Tyndall showed).

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    1. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      http://en.wikipedia.org/wiki/Greenhouse_gas

      "A greenhouse gas (sometimes abbreviated GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect.[1] The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. In the Solar System, the atmospheres of Venus, Mars, and Titan also contain gases that cause greenhouse effects. Greenhouse…

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    2. Timothy Curtin

      Economic adviser

      In reply to David Arthur

      Harrigan said: “Because N2 and O2 are TRANSPARENT to IR they allow the heat to escape to space.” Given that they account for 99% of the atmosphere, if he is right, the IR “blockage” of heat by CO2 at 0.039% has to be insignificant relative to the 99% he says is not blocked by O2 and N2.

      BTW, Harrigan appears not to be aware that John Nicol is a physicist who specialised in research in both radio physics and atomic and molecular physics including high resolution spectroscopy in gases: “The physics…

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    3. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin writes: "First: the radiation releases heat that otherwise would be absorbed, so it has a cooling relative to what would otherwise be the case.

      "Second, Tyndall showed that while [H2O] and [CO2] absorb heat in the IR and then radiate it sooner or later to space, the N2 and O2 do not convey the earth’s heat through the atmosphere or IR."

      Correct, Mr Curtin. The O2 and N2 have absolutely NOTHING to do with the IR. The IR radiation passes through the O2 and N2 AS THOUGH IT IS TRANSPARENT…

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    4. Mark Harrigan

      PhD Physicist

      In reply to Timothy Curtin

      Tim Curtin again shows he cannot post replies in the right place on TC - no matter.

      I have a PhD in Physics - superior qualifications to Mr Nicols - and certainly to Mr Curtin - who claims to be an econometrician. But this is irrelevant. What matters are the facts.

      It would appear Tim is finally starting to understand that N2 and O2 and transparent to IR - but his argument about the relative concentrations of the gases aare irrelevant. All that matters is that CO2 is THERE in sufficient…

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  16. Timothy Curtin

    Economic adviser

    Harrigan: I tried but failed to locate your boring comments. Tant pis, or as we used to say in Cairo when I worked there, malesh.

    You said “It would appear Tim is finally starting to understand that N2 and O2 are transparent to IR - but his argument about the relative concentrations of the gases is irrelevant”. Why? To real scientists, unlike Mark, relative concentrations are everything, when as you claim 99% of the atmosphere allows emission to space of the earth’s heat from the sun, and only…

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    1. Mark Harrigan

      PhD Physicist

      In reply to Timothy Curtin

      More ignorant and irrelevant pish posh from Mr Curtin.

      Tim, I am NOT making claims that contradict established physics and the vast majority of climate science. YOU ARE - so the obligation is on you to publish. Not me.

      As usual you make veiled insults about spelling (never heard of a typo?) but fail to address the core question.

      It's simple. Do you now understand that N2 and O2 are NOT greenhouse gases and that CO2 is and that your many posts on this thread (and others) claiming that N2 and O2 do NOT allow thermal IR to escape but that CO2 does allow IR to escape and therefore produces cooling are TOTALLY WRONG and FALSE or not.

      Yes or No?

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    2. Timothy Curtin

      Economic adviser

      In reply to Mark Harrigan

      Harrigan, I think it is worth reposting on this Discovery of Fire Thread some of John Nicol’s response to you at “The State of the Climate” article, especially as it is clear you have not understood what he said.

      “Thus by contact and by the receipt of energy from collisions with the surface and evaporated water molecules, the passive gases of oxygen and nitrogen are warmed. As they all circulate from the tropics to the mid and higher latitudes, they convey energy to these parts which causes the…

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    3. David Arthur

      resistance gnome

      In reply to Timothy Curtin

      Mr Curtin,

      My understanding is that the bulk of the warm (low latitude) to cold (high latitude) heat transmission that Mr Nicol describes actually occurs in the oceans, not the atmosphere. Perhaps Dr Harrigan can correct this, if necessary?

      In direct contrast to the reported comments of Mr Nicol, air flows TOWARD the equator from ~30 deg N and S, although this may shift N and S with the seasons); that is, toward the region of maximum solar intensity - and the equatorial low pressure belt…

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    4. Mark Harrigan

      PhD Physicist

      In reply to Timothy Curtin

      Tim - I am a physicist - it's on record at the University of Melbourne. What credentials do you claim given you have continued to claim N2 and O2 act as GHGs when it has been shown countless times they are transparent to IR and you have plainly no grasp of the difference between heat and radiation?

      I've understood perfectly what Mr Nicol has said. He's wrong. His contention is contradicted by the evidence. If it were true you would see an INCREASE in the IR band where CO2 acts - the data shows…

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