Does Carbon Dioxide Cool the Earth?
INTRODUCTION
Although the earth’s climate is chaotic and theoretically impossible to predict, we nevertheless continue to fund computer models. The consequences are doomsday scenarios blaming the single factor mankind has any plausible effect upon, namely the trace gas CO2 measured in parts per million. Considering the complexity, this exercise abandons the science of fluid flow equations and substitutes arbitrary curve fit “parameterization”. And as might be expected, no model has yet been able to predict temperatures outside of its calibration interval. It is almost as if the climate chaotically and thus unpredictably staggers from one state to another governed by the infamous “butterfly effect.”
So the question becomes, “In the real world when CO2 levels change, do global temperatures respond?” Fortunately we know both CO2 levels and global temperatures from proxies over geological ages, from centuries of surface records, and from satellites over the last several decades. And to first glance, global temperatures do have a strong dependence on the amount of CO2. Without exception, in all locals and across all time scales, increasing CO2 apparently causes the earth to get colder. This is “negative correlation” and is not in any scientific doubt.
But since this mathematically indisputable fact is so counter-intuitive, all sides scramble to spin the evidence.
ICE CORES AND OTHER PROXIES
Ever since Roald Amundsen and Robert Scott led the first harrowing expeditions to the South Pole in 1911, we have with increasing confidence begun to map this most difficult of continents. In particular, the Russians established a permanent base at “Vostok Station” in the East Antarctic (78°28' S, 106°48'E) which is nearly the coldest place on earth. This research outpost sits at an elevation of 3,488 meters above sea level and on top of more than 420 thousand years of undisturbed yearly snowfall. In 1998, a joint project sponsored by the US, Russia, and France drilled to an incredible depth of 3,623 meters (11,886 feet). The resulting ice cores gave us the atmospheric composition, to include miniscule traces of CO2, directly from trapped air bubbles as well as global temperatures by inference from oxygen isotope ratios. This scientific bonanza provided a record over nearly four complete cycles of ice ages and subsequent warming each complete cycle lasting roughly 100 thousand years [1-2].
Perhaps surprisingly but certainly contrary to wide spread fears, the raw data appears to show that CO2 cools rather than warms the earth. A typical cycle is graphed below [3] and analyzed in more detail in the Appendix : Vostok Ice Cores Indicate CO2 Cools the Earth.
In the graph above as time progresses from left to right, temperatures dramatically rise for some 800-1400 years before the originally low CO2 concentration begins to respond [4-5]. As slowly warming oceans release CO2 to the atmosphere, the temperature rise slows in proportion to the amount of extra CO2 demonstrating an apparent cooling effect. On the trailing edge of the cycle, CO2 remains high for twenty thousand years apparently driving temperatures down as the earth enters a new ice age. For those challenged by the manifest truth of these empirical mathematical correlations, unburdened by considerations of physical mechanisms, the data is unequivocal. At first glance CO2 unmistakably appears to cool the earth.
But of course this undeniable negative correlation, or indeed any correlation, does not mean causation. Since the time of Arrhenius in the late 1800s (q.v. the Appendix on Arrhenius Activation), the scientific community began to suspect that the “greenhouse” gas of water vapor warms the planet. More recently we know the actual mechanism is molecular absorption and re-radiation which incidentally was only explained with the invention of quantum mechanics notably by Niles Bohr from 1913-1923.
When a theory, like CO2 being an important driver of global temperatures, makes predictions contrary to what we observe in real world measurements, it has failed the prime test of science. Contrary to what fear mongering liberal politicians would have you believe, science would say that “global warming” has been “falsified”. And so there must be something wrong with the assumptions on which the theory is based. The obvious answer is that trace amounts of CO2 have no measurable effect on global temperatures.
Apparently the parts-per-million changes in CO2 are so inconsequential, they barely tweak the thermometer. Rather it is water vapor that determines temperatures and everything else gets lost in the noise. But this is what any scientist would have predicted at the start because H20 is as much as two orders of magnitude more abundant than CO2 and each molecule of H2O contributes an order of magnitude more warming. This is because CO2 lacks a permanent dipole moment and is not even a “real” greenhouse gas to first approximation. CO2 only has any contribution because it absorbs and re-radiates weakly in a narrow frequency band where nothing else does.
And again this should not be surprising. Variations in the Earth’s orbit (q.v. Milankovitch cycles) which change solar irradiance, solar magnetic activity in the form of sunspots (q.v. Maunder Minimum) which control cloud cover, chaotic weather cycles and especially negative feedback loops of all descriptions but especially for water vapor, all of these and more besides are wildly variable energy flows which are orders of magnitude more influential than any possible effect of CO2 measured in parts per million.
Indeed, calculations from the IPCC for a “static” layered atmosphere without the cooling convection of winds and weather give the temperature increase versus CO2 as follows [6]:
CO2 ppm |
Cumulative °C |
Extra °C |
Cumulative °F |
Extra °F |
0->100 |
2.22 |
2.22 |
4.00 |
4.00 |
100->200 |
2.51 |
0.29 |
4.52 |
0.52 |
200->300 |
2.65 |
0.14 |
4.77 |
0.25 |
300->400 |
2.71 |
0.06 |
4.88 |
0.11 |
400->600 |
2.79 |
0.08 |
5.02 |
0.14 |
600->1000 |
2.85 |
0.06 |
5.13 |
0.11 |
Note that the same calculations for water vapor (without convection currents and at an average concentration of 2.5%) predict a global warming of some 150-170 degrees Fahrenheit. This makes the “static” CO2 contribution of 4.9 degrees about 2-3% of the total. Interestingly, negative feedback from the chaotic weather reduces the “static” H2O warming by more than 110 degrees Fahrenheit. Unfortunately the weather is mathematically “chaotic” and thus theoretically impossible to model. But as it is the same physical mechanism, similar considerations must also apply to CO2. If so, this would reduce the incremental CO2 heating of 0.11 degrees Fahrenheit (for increases of 300->400 ppm) to 0.04 degrees Fahrenheit which is unobservable but would explain all the ice core data.
Nevertheless, to maintain the funding and the hysteria, warming alarmists arbitrarily increase temperature predictions by a factor of 10-30 using curve fitting polynomials (i.e. from 0.11 degrees for a CO2 increase of 300->400 ppm to an incredible 3.0 degrees or more). This abandonment of the basic science of Navier-Stokes equations governing fluid flow and substituting curve fit polynomials based on “intuition” allows any desired result. What gives any cover to this fraud is that the climate is theoretically impossible to model. Minute differences in the starting point of the calculations change model predictions from catastrophic warming to sudden lurches into ice ages. Hopefully it is also obvious that accumulating theoretically unpredictable non-linear results (at great expense) results in increasing uncertainty rather than “averaging out”.
That is to say, the alarmists effectively take a ruler and draw straight lines through chaotic and mathematically noisy temperature plots. What should give the public pause, but does not, is that any imagined correlation between CO2 and warming is entirely absent in all real world data sets. Rather CO2 always appears to cool the earth. But hope springs eternal and many charlatans earn a good living as financial advisors drawing straight lines through stock prices which also exhibit chaotic behavior.
Another incredible spin is that “everybody knows” excess CO2 causes global warming, but since we don’t see that in the raw data but rather the exact opposite, perhaps the initially rising temperatures, which are necessarily from other causes, because CO2 levels don’t change for the first 800-1400 years, are somehow later amplified by CO2 when it does increase. But the fact the temperature rise never gets steeper, seems to definitively dispel this notion. Rather as CO2 increases, the slope of the temperature rise decreases with time, exactly as if CO2 had a strong braking effect on warming. And finally on the trailing end of the cycle the CO2 level remains high for twenty thousand years while global temperatures are driven down demonstrating again CO2’s apparent cooling effect.
Nor is the observation of CO2 always lagging temperature in any way mysterious. Over a 100 thousand year cycle, as oceans cool they absorb CO2 at prodigious rates and then return CO2 to the atmosphere as they warm up again. This process is accurately described by the well known solubility of CO2 in sea water and predictions track exactly the observed ice core record of global temperatures. The oceans also have a tremendous thermal inertia and lag air temperatures by some centuries, again as is precisely observed. Finally the massive amount of CO2 in the oceans dwarfs the paltry amount in the atmosphere and equilibrium between the two is measured to occur with a half life of roughly 4-6 years. The obvious conclusion based on the science can only be that CO2 responds to but does not cause warming.
But the bottom line is that in the real world, the physical “cause” must come before the resulting “effect”. To believe trace amounts of CO2 have any effect on global temperatures, this logical principle on which all of science is based must be abandoned (see the Appendix: Nine Inconvenient Truths). This twisted logic may be acceptable to politically gullible “true-believers” on band wagons out to save the world, to newspaper editors wanting to increase circulation, to a thankfully few academics selling their souls for research grants by misrepresenting the data, and to all power-hungry politicians seeking a cause to exploit, but it is not science.
SURFACE RECORDS
Nor do surface measurements of temperature show any noticeable increase over the last century or so. Note that to maintain both the hysteria and the funding, “adjustments” were made by government bureaucrats (to include those in the IPCC) to the raw unfiltered data.
What government bureaucrats missed, giving lie to other adjustments, is the unfiltered report of unusually hot days. This shows recent years are NOT the hottest ever but in fact temperatures have been getting cooler even as CO2 has dramatically increased.
SATELLITE MEASUREMENTS
Nor do measurements of surface temperatures from orbit show any dependence on CO2. And these measurements are taken across the entire world many times per day. Indeed these data sets are many uncountable billions of times larger than all previous human measurements combined. Satellite measurements are also in exact agreement with long standing weather balloon data.
Satellites clearly show that global temperatures across the entire earth have been slightly cooling for the entirety of the 21st century despite rising CO2 levels (caused by a slightly warming ocean). Again we note satellite measurements are more accurate and geographically widespread than any in history and demonstrate CO2 is negatively correlated with temperature as seen in all data sets with longer time baselines.
That computer models continue to predict cataostrophic warming which is not observed in real world measurements is perhaps to be expected. These models have abandoned “ab initio” scientific principles of theoretical physics and are effectively arbitrary curve-fit parameterizations. And even more, these models try to simulate chaotic systems which have been mathematically proven to be theoretically impossible to model. What is not expected is that these convenient computer results, which grossly fail to predict real world observations, are not discarded. But rather these failed doomsday scenarios receive acolades from pandering politicians who try to frighten a scientific illiterate populace to personal advantage (q.v. the Appendix : Nine Inconvenient Truths).
CONCLUSIONS
All any reasonable person can say is that changes in CO2 are observed to have no effect on global temperature. The alternative is to believe, as the data clearly indicates without exception, that CO2 does have an effect but that is to cool the earth rather than to warm it up. Take your choice. The data and the science are unequivocal.
REFERENCES
1. Petit, J.R., I. Basile, A. Leruyuet, D. Raynaud, C. Lorius, J. Jouzel, M. Stievenard, V.Y. Lipenkov, N.I. Barkov, B.B. Kudryashov, M. Davis, E. Saltzman, and V. Kotlyakov. 1997. Four climate cycles in Vostok ice core. Nature 387: 359-360.
2. Petit, J.R., J. Jouzel, D. Raynaud, N.I. Barkov, J.-M. Barnola, I. Basile, M. Benders, J. Chappellaz, M. Davis, G. Delayque, M. Delmotte, V.M. Kotlyakov, M. Legrand, V.Y. Lipenkov, C. Lorius, L. Pépin, C. Ritz, E. Saltzman, and M. Stievenard. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.
3. http://joannenova.com.au/globalwarming/graphs/vostok-ice-cores-150000.jpg
a) Indermühle et al. (GRL, vol. 27, p. 735, 2000), who find that CO2 lags behind the temperature by 1200±700 years, using Antarctic ice-cores between 60 and 20 kyr before present (see figure).
b) Fischer et al. (Science, vol 283, p. 1712, 1999) reported a time lag 600±400 yr during early de-glacial changes in the last 3 glacial–interglacial transitions.
c) Siegenthaler et al. (Science, vol. 310, p. 1313, 2005) find a best lag of 1900 years in the Antarctic data.
d) Monnin et al. (Science vol 291, 112, 2001) find that the start of the CO2 increase in the beginning of the last interglacial lagged the start of the temperature increase by 800 years.
6. Data from the IPCC Published Report TAR3, Chapter 6. Radiative Forcing of Climate Change: Section 6.3.4 “Total Static Layered Atmosphere Calculation of Temperature Increase for Greenhouse Gas Forcing”
APPENDIX: VOSTOK ICE CORES INDICATE CO2 COOLS THE EARTH
And just what do the Vostok Ice Cores tell us about the dependence of global temperature on trace amounts of CO2? Apparently, this pernicious molecule causes global cooling because the more polluting CO2 there is in the air, the colder it gets. And when CO2 levels get small enough, only then do we have massive warming. If this seems confounding in light of non-stop Congressional calls for a “global warming tax” on CO2 emissions, just take another look at the real world data from Vostok graph.
From 150-140 thousand years ago the oceans had been getting colder absorbing CO2 out of the air. Apparently by 135 thousand years ago, there wasn’t enough CO2 around to keep everything cold. So the world was released from the mysterious cooling effect of CO2 but in any event started to warm up really fast.
For the first few thousands of years the slope of the temperature rise didn’t change perhaps because neither did CO2 from its very low levels. Considering their massive heat capacity no one should be surprised it took that long for the oceans to warm and to start releasing CO2 back into the air. But by about 130 thousand years ago, there was apparently enough CO2 to start cooling everything again and the temperature increase stopped its rapid rise and began to level off.
To better illustrate the mathematical relation, the Vostok ice core results are smoothed to reduce the noise as shown below.
Note that if CO2 warmed instead of cooled the earth, we would expect the temperature rise to get steeper (“not observed” green line above) instead of decreasing (“observed” purple line above). So what the data unambiguously shows is that CO2 does not amplify the original warming (necessarily from other causes) but apparently reduces it. This of course assumes CO2 has any effect at all on global temperature. In the original graph from 135-130 thousand years ago, the same negative correlation is clearly visible without the slightest trace of any CO2 warming “amplification”. Rather we observe the exact opposite.
From about 130 to 110 thousand years ago, CO2 levels remained at its highest levels apparently driving global temperatures relentlessly down again. Finally at about 110 thousand years ago, the oceans got cold enough to start absorbing CO2 and concentrations began to decrease. With that, the earth was again apparently released from CO2 caused cooling, and started to warm up again in the next cycle. And the cycle repeated albeit with a little chaotic noise possibly attributable to random-walk weather patterns and continents ever so slightly shifting positions on tectonic plates.
But this mathematically accurate description creates a conundrum because our sense of physical mechanisms predicts exactly the opposite. Obviously something is wrong, so perhaps we should re-examine our assumptions. The obvious resolution to this mess is that, assuming CO2 has anything do with global temperatures, is grossly wrong. That is to say we have put the cart before the horse. Rather CO2 responds to temperature but does not affect it. Nor is this unreasonable noting the paucity of CO2, considering its pitifully weak ability to retain heat, and because the chaotic climate significantly reduces all greenhouse warming. Rather the effect of CO2 is perhaps like going outside to smoke a cigarette. The heating effect of either is real but way too small to measure.
Global warming activists find this so distressing they attack the accuracy of the real world observations which so clearly and consistently indicate CO2 cooling. Unfortunately temperature measurements have been repeated across too many time scales and in too many locales. And they all, without exception, demonstrate the same apparent CO2 cooling effect in the raw data.
So we are left with two distinct choices. Either CO2 has so little effect on global temperature, if any at all, we can’t measure it; or CO2 does have a measurable effect which is to cool the earth. To believe otherwise is to believe CO2 causes massive warming but 800-1400 years before CO2 begins to increase. Think we need more science education?
APPENDIX: ARRHENIUS ACTIVATION
Svante Arrhenius (1859-1927) was a Swedish physicist awarded the 1903 Nobel Prize for the dissolution of electrolytes leading to his famous equation for thermal activation. This equation is generally introduced in entry-level chemistry in high school and a staple of modern physical chemistry studies thereafter.
Unfortunately he was a product of his times and also promoted the now discredited ideas of racial superiority (a director of the Swedish Society for Racial Hygiene), the formation of the solar system and planets due to an interstellar collision, the origin of life from spores transferred throughout the galaxy by light pressure (panspermism), and fundamentally flawed estimates of global warming from water vapor and CO2.
In regards to global warming, his simplistic early estimates got the science wrong by neglecting atomic spectra. He also neglected clouds and heat flow due to convection assuming a static layered atmosphere giving results that we now know were several orders of magnitude too large. Unlike Arrhenius, physicist Kunt Angstrom actually made quantitative measurements of the heat absorption spectra and correctly noted that Arrhenius’ calculation neglected saturation effects making additional contributions of CO2 insignificant. On the other hand, Arrhenius’ undeniable contribution was to simply note, among others at the time, that our greenhouse gas, i.e. overwhelmingly water vapor, has a significant effect on global temperatures.
APPENDIX: NINE INCONVENIENT TRUTHS
In the United Kingdom, High Court Judge Michael Burton ruled that the film an “Inconvenient Truth” starring Al Gore and directed by Davis Guggenheim contains at least nine serious scientific errors. And further that these misrepresentations and outright falsehoods must be disclosed before any screening of the film. Basically the judge ruled that the “apocalyptic vision” was politically partisan propaganda rather than an impartial scientific analysis.
Considering the undeniable intelligence of the producers and especially Mr. Gore these fabrications can only be considered deliberate lies. That Al Gore subsequently traded his Oscar winning accolades for his film “An Inconvenient Truth”, and the consequent Nobel Prize for the “Politics of Peace”, into well over 100 million dollars in “consulting fees” for trading “cap and trade” tax credits, is yet another outrage. Basically Al threatens boycotts and demonstrations against any Corporation not hiring him.
This “corporate blackmail” of course comes out of corporate earnings and results in widespread commodity price increases which preferentially hurt the poor who have no excess disposable income. It is based on lies and a corruption of science, it is shameful and a theft of public monies, and at its root, immoral.
In any event the British High Court besides condemning the film as a political screed made nine legally binding findings that it required must be stated before any showing of the film.
1. Former Vice President Al Gore claimed that the rise in C02 over a period of 650,000 years, showed "an exact fit" to temperature increase. The judge ruled that was a misrepresentation of the scientific data which in fact showed the exact opposite; namely that the temperature dramatically rose for more than 1000 years before any change in very low CO2 concentrations. The specific wording of the court was "the two graphs do not establish what Mr. Gore asserts".
2. The documentary claims the sea level will rise some 20 feet in the “near future.” Rather the science shows this worst case scenario is based on faulty numbers and in any event from the rate stated would take more than 25 thousand years. Instead satellite measurements show both Greenland and Antarctica are currently gaining in ice mass lowering the sea level. This is because slightly warmer air is more humid and dumps more snowfall on the glaciers.
3. The film claims that low-lying inhabited Pacific atolls "are being inundated because of anthropogenic global warming" but the judge ruled there was no evidence of any for any such sea level rise having yet happened.
4. The documentary speaks of global warming "shutting down the Ocean Conveyor." This is the process by which warm water from the tropics is carried by the North Atlantic Gulf Stream to Western Europe. Citing consensus findings from the Intergovernmental Panel on Climate Change (IPCC), the judge noted the published summary stated "it is very unlikely" that the “Meridional Overturning Circulation” would shut down since no scientific calculation validated this fear and failing that there was no historical or empirical evidence.
5. Mr. Gore says the disappearance of snow on Mt Kilimanjaro was directly attributable to global warming. But the judge noted that actual measurements from Central Africa showed a slightly declining temperature and that instead all the scientific papers attributed the snow loss to a wide spread deforestation and a consequent reduction in humidity. That is the temperatures never got warm enough on the mountain to melt the snow but rather drying winds tended to sublimate it.
6. The film contends that the drying of Lake Chad is a prime example of a catastrophic result of global warming but the judge ruled there was insufficient evidence to support this supposition. Rather all the publications and scientific data demonstrated that "it is far more likely to result from population increase and over-grazing, and regional climate variability."
7. Mr. Gore blames Hurricane Katrina and the consequent devastation in New Orleans on global warming, but the judge ruled there was "insufficient evidence to show that". Rather the undeniable record is that warmer temperatures significantly reduce random violent weather events. Basically warming reduces temperature gradients which is the useful energy for powering violent weather, creates wind shear which disrupts Atlantic hurricane formation (i.e. no hurricanes at all during global warming “El Nino” events), and adds more entropy in the form of evaporation-condensation cycles further removing the energy available to power winds.
8. Mr. Gore cites a scientific study that shows, for the first time, that polar bears were being found after drowning from "swimming long distances of up to 60 miles to find the ice." The judge ruled that "The only scientific study that either side before me can find is one which indicates that four polar bears have recently been found drowned because of a storm … and it plainly does not support Mr. Gore's description". Rather the polar bear population has increased from roughly 5000 in the 1950s to more than 30,000 today both because of a reduction of hunting and because of more vegetation supporting more prey in a warmer more hospitable world.
9. Mr. Gore claimed that coral reefs all over the world were being bleached because of global warming and other factors. Again citing the IPCC, the judge ruled that separating the impacts of stresses due to climate change from other stresses, such as over-fishing, and pollution was difficult if not impossible.
Think we need more science education and less left-wing fear mongering lies?