What Do We Think About Climate Change

More from on CO2 residence time and the recent studies on this issue:

Tom V. Segalstad
Associate Professor of Resource and Environmental Geology
The University of Oslo, Norway
5 August 2009

In a paper recently published in the international peer-reviewed journal Energy & Fuels, Dr. Robert H. Essenhigh (2009), Professor of Energy Conversion at The Ohio State University, addresses the residence time (RT) of anthropogenic CO2 in the air. He finds that the RT for bulk atmospheric CO2, the molecule 12CO2, is ~5 years, in good agreement with other cited sources (Segalstad, 1998), while the RT for the trace molecule 14CO2 is ~16 years. Both of these residence times are much shorter than what is claimed by the IPCC. The rising concentration of atmospheric CO2 in the last century is not consistent with supply from anthropogenic sources. Such anthropogenic sources account for less than 5% of the present atmosphere, compared to the major input/output from natural sources (~95%). Hence, anthropogenic CO2 is too small to be a significant or relevant factor in the global warming process, particularly when comparing with the far more potent greenhouse gas water vapor. The rising atmospheric CO2 is the outcome of rising temperature rather than vice versa. Correspondingly, Dr. Essenhigh concludes that the politically driven target of capture and sequestration of carbon from combustion sources would be a major and pointless waste of physical and financial resources.

-------------------------------------------------------------------------------------------------------------------

Essenhigh (2009) points out that the IPCC (Intergovernmental Panel on Climate Change) in their first report (Houghton et al., 1990) gives an atmospheric CO2 residence time (lifetime) of 50-200 years [as a "rough estimate"]. This estimate is confusingly given as an adjustment time for a scenario with a given anthropogenic CO2 input, and ignores natural (sea and vegetation) CO2 flux rates. Such estimates are analytically invalid; and they are in conflict with the more correct explanation given elsewhere in the same IPCC report: "This means that on average it takes only a few years before a CO2 molecule in the atmosphere is taken up by plants or dissolved in the ocean".

Some 99% of the atmospheric CO2 molecules are 12CO2 molecules containing the stable isotope 12C (Segalstad, 1982). To calculate the RT of the bulk atmospheric CO2 molecule 12CO2, Essenhigh (2009) uses the IPCC data of 1990 with a total mass of carbon of 750 gigatons in the atmospheric CO2 and a natural input/output exchange rate of 150 gigatons of carbon per year (Houghton et al., 1990). The characteristic decay time (denoted by the Greek letter tau) is simply the former value divided by the latter value: 750 / 150 = 5 years. This is a similar value to the ~5 years found from 13C/12C carbon isotope mass balance calculations of measured atmospheric CO2 13C/12C carbon isotope data by Segalstad (1992); the ~5 years obtained from CO2 solubility data by Murray (1992); and the ~5 years derived from CO2 chemical kinetic data by Stumm & Morgan (1970).

Revelle & Suess (1957) calculated from data for the trace atmospheric molecule 14CO2, containing the radioactive isotope14C, that the amount of atmospheric "CO2 derived from industrial fuel combustion" would be only 1.2% for an atmospheric CO2 lifetime of 5 years, and 1.73% for a CO2 lifetime of 7 years (Segalstad, 1998). Essenhigh (2009) reviews measurements of 14C from 1963 up to 1995, and finds that the RT of atmospheric 14CO2 is ~16 (16.3) years. He also uses the 14C data to find that the time value (exchange time) for variation of the concentration difference between the northern and southern hemispheres is ~2 (2.2) years for atmospheric 14CO2. This result compares well with the observed hemispheric transport of volcanic debris leading to "the year without a summer" in 1816 in the northern hemisphere after the 1815 Tambora volcano cataclysmic eruption in Indonesia in 1815.

Sundquist (1985) compiled a large number of measured RTs of CO2 found by different methods. The list, containing RTs for both 12CO2 and 14CO2, was expanded by Segalstad (1998), showing a total range for all reported RTs from 1 to 15 years, with most RT values ranging from 5 to 15 years. Essenhigh (2009) emphasizes that this list of measured values of RT compares well with his calculated RT of 5 years (atmospheric bulk 12CO2) and ~16 years (atmospheric trace 14CO2). Furthermore he points out that the annual oscillations in the measured atmospheric CO2 levels would be impossible without a short atmospheric residence time for the CO2 molecules.

Essenhigh (2009) suggests that the difference in atmospheric CO2 residence times between the gaseous molecules 12CO2 and 14CO2 may be due to differences in the kinetic absorption and/or dissolution rates of the two different gas molecules.

With such short residence times for atmospheric CO2, Essenhigh (2009) correctly points out that it is impossible for the anthropogenic combustion supply of CO2 to cause the given rise in atmospheric CO2. Consequently, a rising atmospheric CO2 concentration must be natural. This conclusion accords with measurements of 13C/12C carbon isotopes in atmospheric CO2, which show a maximum of 4% anthropogenic CO2 in the atmosphere (including any biogenic CO2), with 96% of the atmospheric CO2 being isotopically indistinguishable from "natural" inorganic CO2 exchanged with and degassed from the ocean, and degassed from volcanoes and the Earth's interior (Segalstad, 1992).

Essenhigh (2009) discusses alternative ways of expressing residence time, like fill time, decay time, e-fold time, turnover time, lifetime, and so on, and whether the Earth system carbon cycle is in dynamic equilibrium or non-equilibrium status. He concludes (like Segalstad, 1998) that the residence time is a robust parameter independent of the status of equilibrium, and that alternative expressions of the residence time give corresponding values.

It is important to compare Essenhigh's (2009) results with a recently published paper in PNAS by Solomon et al. (2009), the first author of which (Susan Solomon) co-chairs the IPCC Working Group One, the part of the IPCC that deals with physical climate science. This paper was published after Essenhigh had submitted his manuscript to Energy & Fuels.

The message of Solomon et al. (2009) is that there is an irreversible climate change due to the assimilation of CO2 in the atmosphere, solely due to anthropogenic CO2 emissions. From quantified scenarios of anthropogenic increases in atmospheric CO2, their implication is that the CO2 level flattens out asymptotically towards infinity, giving a residence time of more than 1000 years (without offering a definition or discussion of residence time or isotopic differences): "a quasi-equilibrium amount of CO2 is expected to be retained in the atmosphere by the end of the millennium that is surprisingly large: typically ~40% of the peak concentration enhancement over preindustrial values (~280 ppmv)". The authors' Fig. 1, i.a. shows a peak level at 1200 ppmv atmospheric CO2 in the year 2100, levelling off to an almost steady level of ~800 ppmv in the year 3000. It is not known how their 40% estimate was derived.

Solomon et al. (2009) go on to say that "this can be easily understood on the basis of the observed instantaneous airborne fraction (AFpeak) of ~50% of anthropogenic carbon emissions retained during their build-up in the atmosphere, together with well-established ocean chemistry and physics that require ~20% of the emitted carbon to remain in the atmosphere on thousand-year timescales [quasi-equilibrium airborne fraction (AFequil), determined largely by the Revelle factor governing the long-term partitioning of carbon between the ocean and atmosphere/biosphere system]".

Solomon et al. (2009) have obviously not seriously considered the paper by Segalstad (1998), who addresses the 50% "missing sink" error of the IPCC and shows that the Revelle evasion "buffer" factor is ideologically defined from an assumed model (atmospheric anthropogenic CO2 increase) and an assumed pre-industrial value for the CO2 level, in conflict with the chemical Henry's Law governing the fast ~1:50 equilibrium partitioning of CO2 between gas (air) and fluid (ocean) at the Earth's average surface temperature. This CO2 partitioning factor is strongly dependent on temperature because of the temperature-dependent retrograde aqueous solubility of CO2, which facilitates fast degassing of dissolved CO2 from a heated fluid phase (ocean), similar to what we experience from a heated carbonated drink.

Consequently, the IPCC's and Solomon et al.'s (2009) non-realistic carbon cycle modelling and misconception of the way the geochemistry of CO2 works simply defy reality, and would make it impossible for breweries to make the carbonated beer or soda "pop" that many of us enjoy (Segalstad, 1998).

So why is the correct estimate of the atmospheric residence time of CO2 so important? The IPCC has constructed an artificial model where they claim that the natural CO2 input/output is in static balance, and that all CO2 additions from anthropogenic carbon combustion being added to the atmospheric pool will stay there almost indefinitely. This means that with an anthropogenic atmospheric CO2 residence time of 50 - 200 years (Houghton, 1990) or near infinite (Solomon et al., 2009), there is still a 50% error (nicknamed the "missing sink") in the IPCC's model, because the measured rise in the atmospheric CO2 level is just half of that expected from the amount of anthropogenic CO2 supplied to the atmosphere; and carbon isotope measurements invalidate the IPCC's model (Segalstad, 1992; Segalstad, 1998).

The correct evaluation of the CO2 residence time -- giving values of about 5 years for the bulk of the atmospheric CO2 molecules, as per Essenhigh's (2009) reasoning and numerous measurements with different methods -- tells us that the real world's CO2 is part of a dynamic (i.e. non-static) system, where about one fifth of the atmospheric CO2 pool is exchanged every year between different sources and sinks, due to relatively fast equilibria and temperature-dependent CO2 partitioning governed by the chemical Henry's Law (Segalstad 1992; Segalstad, 1996; Segalstad, 1998).

Knowledge of the correct timing of the whereabouts of CO2 in the air is essential to a correct understanding of the way nature works and the extent of anthropogenic modulation of, or impact upon, natural processes. Concerning the Earth's carbon cycle, the anthropogenic contribution and its influence are so small and negligible that our resources would be much better spent on other real challenges that are facing mankind.

Tom V. Segalstad
Associate Professor of Resource and Environmental Geology
The University of Oslo, Norway
Personal web page: www.CO2web.info

References
Essenhigh, R.E. 2009: Potential dependence of global warming on the residence time (RT) in the atmosphere of anthropogenically sourced carbon dioxide. Energy & Fuels 23: 2773-2784. http://pubs.acs.org/doi/abs/10.1021/ef800581r

Houghton, J.T., Jenkins, G.J. & Ephraums, J.J. (Eds.) 1990: Climate Change. The IPCC Scientific Assessment. Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge: 365 pp.

Murray, J.W. 1992: The oceans. In: Butcher, S.S., Charlson, R.J., Orians, G.H. & Wolfe, G.V. (Eds.): Global biogeochemical cycles. Academic Press: 175-211.

Revelle, R. & Suess, H. 1957: Carbon dioxide exchange between atmosphere and ocean and the question of an increase of atmospheric CO2 during past decades. Tellus 9: 18-27.

Segalstad, T. V. 1982: Stable Isotope Analysis. In: Stable Isotopes in Hydrocarbon Exploration, Norwegian Petroleum Society 6904, Stavanger: 21 pp. Available at: http://www.co2web.info/STABIS-ANAL.pdf

Segalstad, T. V. 1992: The amount of non-fossil-fuel CO2 in the atmosphere. AGU Chapman Conference on Climate, Volcanism, and Global Change. March 23-27, 1992. Hilo, Hawaii. Abstracts: 25; and poster: 10 pp. Available at: http://www.co2web.info/hawaii.pdf

Segalstad, T. V. 1996: The distribution of CO2 between atmosphere, hydrosphere, and lithosphere; minimal influence from anthropogenic CO2 on the global "Greenhouse Effect". In Emsley, J. (Ed.): The Global Warming Debate. The Report of the European Science and Environment Forum. Bourne Press Ltd., Bournemouth, Dorset, U.K. [ISBN 0952773406]: 41-50. Available at: http://www.co2web.info/ESEFVO1.pdf

Segalstad, T. V. 1998: Carbon cycle modelling and the residence time of natural and anthropogenic atmospheric CO2: on the construction of the "Greenhouse Effect Global Warming" dogma. In: Bate, R. (Ed.): Global warming: the continuing debate. ESEF, Cambridge, U.K. [ISBN 0952773422]: 184-219. Available at: http://www.co2web.info/ESEF3VO2.pdf

Solomon, S., Plattner, G.-K., Knutti, R. & Friedlingstein, P. 2009: Irreversible climate change due to carbon dioxide emissions. Proceedings of The National Academy of Sciences of the USA [PNAS] 106, 6: 1704-1709. http://www.pnas.org/content/106/6/1704.full

Stumm, W. & Morgan, J.J. 1970: Aquatic chemistry: an introduction emphasizing chemical equilibria in natural waters. Wiley-Interscience: 583 pp.

Sundquist, E.T. 1985: Geological perspectives on carbon dioxide and the carbon cycle. In: Sundquist, E.T. & Broecker, W.S. (Eds.): The carbon cycle and atmospheric CO2: natural variations Archean to present. American Geophysical Union, Geophysical Monograph 32: 5-59.

 

An interesting book, available to be read on-line and PDF download:

(NAS Colloquium) Carbon Dioxide and Climate Change (1997)
http://www.nap.edu/catalog.php?record_id=6238

 

So Essenhigh and Solomon et al were published at about the same time, and came to different conclusions. Both papers were apparently peer-reviewed and presented in reputable journals.

Segelstad wrote this article to support Essenhigh. In doing so, he refers us to several of his own papers from 12 to 18 years ago.

May I say that hardly amounts to overwhelming proof that Solomon and her co-authors are the ones in error? If Segelstad's arguments were as obvious and self-evident as he believes, you'd think he could find someone to reference besides himself.

That doesn't automatically make him wrong, of course. But it does give him a little less credibility in my eyes.

 

To all the exhausts of all the infernal destruction engines on the planet, add the gasses produced by the heating of all high latitude homes on the planet, and the air conditioning of many low latitude homes, and you have a huge effect .
Yes ,there may be many other non-man made causes of global warming, but adding to them with our own CO2 output doesn't improve the situation , nor slow the process and their effects any. While there are many things we can do nothing about, it would be foolish to not try change the things we can, given how high the stakes are..

 

Al Gore himself inserted politics into a scientific debate. Or did he insert pseudo-science into a political debate? It is so f3kcued now who cares. If the honey truck turns left the 5h17 slops to the right and if the honey truck turns right the 5h17 slops to the left. Either way it smells the same. Don't let the honey truck fall over or it will be everywhere ala hit the fan.

 

A reasonable request and stop using ether. It is no good for you.

 

May be? There is 1 cause for global warming. Solar radiation. The rest is a drop in the ocean, negligible and transient. Man's contribution is so miniscule as to be negligible.

 

Now let me post something else about Solomon:

Contributions of Stratospheric Water Vapor to Decadal Changes in the Rate of Global Warming
Susan Solomon, Karen H. Rosenlof, Robert W. Portmann, John S. Daniel, Sean M. Davis, Todd J. Sanford, Gian-Kasper Plattner.
Originally published in Science Express on 28 January 2010
http://www.sciencemag.org/cgi/content/abstract/science.1182488

Abstract
"Stratospheric water vapor concentrations decreased by about 10% after the year 2000. Here we show that this acted to slow the rate of increase in global surface temperature over 2000–2009 by about 25% compared to that which would have occurred due only to carbon dioxide and other greenhouse gases. More limited data suggest that stratospheric water vapor probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30% as compared to estimates neglecting this change. These findings show that stratospheric water vapor is an important driver of decadal global surface climate change."


The authors write that "the trend in global surface temperatures has been nearly flat since the late 1990s despite continuing increases in the forcing due to the sum of the well-mixed greenhouse gases (CO2, CH4, halocarbons, and N2O), raising questions regarding the understanding of forced climate change, its drivers, the parameters that define natural internal variability, and how fully these terms are represented in climate models.

Solomon et al. used observations of stratospheric water vapor concentration obtained over the period 1980-2008, together with detailed radiative transfer and modeling information, in order to calculate the global climatic impact of this important greenhouse gas and compare it with trends in mean global near-surface air temperature that were observed over the same time period.

The seven scientists report that stratospheric water vapor concentrations decreased by about 10% after the year 2000; and their analysis indicates that this decrease should have slowed the rate of increase in global near-surface air temperature between 2000 and 2009 by about 25% compared to what would have been expected (on the basis of climate model calculations) due to measured increases in carbon dioxide and other greenhouse gases over the same time period. In addition, they found that "more limited data suggest that stratospheric water vapor probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30% [above what it would have been without the stratospheric water vapor increase]."

In their concluding paragraph, Solomon et al. write that it is "not clear whether the stratospheric water vapor changes represent a feedback to global average climate change or a source of decadal variability." In either case, their findings elucidate a hugely important phenomenon that was not previously included in any prior analyses of global climate change. They also write that current climate models do not "completely represent the Quasi Biennial Oscillation [which has a significant impact on stratospheric water vapor content], deep convective transport [of water vapor] and its linkages to sea surface temperatures, or the impact of aerosol heating on water input to the stratosphere."

Consequently, in light of Solomon et al.'s specific findings, their listing of what current climate models do not do (which they should do), and the questions they say are raised by the flat-lining of mean global near-surface air temperature since the late 1990s, it seem to be premature in the extreme to think that we know enough about the intricate workings of earth's climate self-regulatory system to drastically reduce our CO2 emissions, especially in ways that would radically alter our economies and threaten the present and future of the poorest countries.

Cheers.

 

Gaads you are more dense and myopic than I thought.

But for once you raised a point worth pursuing. Please post the results of the other surveys and polls among scientists and the sponsor of the survey along with the methodology used. Of course it would be too much to ask the names of the respondents to find out if they are real like the signers of the Petition Project put down their names state by state.

 

Look at the list I posted earlier. Not only are Essenhigh and Segalstad in agreement with each other, but with all the others who have ever done a measurement study.

And no matter what, Solomon et al WAS NOT A MEASUREMENT STUDY! It was based (once again) on computer modeling, NOT actual measurements. The basic ASSUMPTION that they are feeding the models is that "all or nearly all" of the recent rise in atmospheric CO2 is due to anthropogenic emissions. The output of such models CANNOT then be cited as proof that either:

1) anthropogenic CO2 has caused the rise or

b) that CO2 has a long residence time.

To site such a study in either way is pure circular reasoning!

When you go back and look at the list of residence time studies, note how often Revelle and Seuss come up. Revelle is the Revelle mentioned by Al Gore in "An Inconvenient Truth" as having alerted him to the danger of AGW via CO2 emissions (Nevermind that Revelle reconsidered the entire narrative before he died )

Jimbo

 

Actually, I think you're more than just a conspiracy theorist. When you start claiming that environmentalists are more of a threat than the worst mass murderers in history, you're more of an irrational, paranoid nut.

Although there are a few kooks on either side of the issue, environmentalists and climatologists as a whole do not want to 'deindustrialize and dehumanize' the world.' That's a lurid bit of melodramatic nonsense. If you're saying it because you actually believe it, instead of exaggerating to make a point, you're somewhat unhinged.

The more of that sort of horse apples I read, the less respect I have for the case you're trying to present.

 

No. I'm not going to bother. If you really believe a bought-and-paid-for propaganda campaign like the Oregon Petition is legitimate, you have such a tenuous grip on reality that it would be a waste of my time and yours to show you anything else.

And of course, science isn't decided by surveys and polls anyway. It's decided by research. I will point out, however, that you can't name a single legitimate scientific society anywhere in the developed world which takes the position AGW is phony. The best you could do is come up with a minor handful that claim to be neutral on the subject--like the American Society of Petroleum Geologists.

 

If that statement were true then one would expect temperatures on the moon to be about the same as temperatures at the earth's surface.

 

"you can't name a single legitimate scientific society anywhere in the developed world which takes the position AGW is phony" - In general, people who have jobs don't much hang around in "scientific societies". Whether to promote an academic program, to give each other a sense of purpose, or to acquire grants to support further study (more study/less holding of a job entailing actual "work"), the planets aligned this time - not to cause global warming but for a bloated academia to find purpose and explain what those field trips with the cute coeds were for.
Turns out, "nothin' new over here" doesn't get as much copy, nor as much funding, as "the - world - is - going - to - end". Even with everything, including politicians jumping on the bandwagon to villanize those evil corporate shill "so-called scientists", business in general, and the people with jobs (face it - "conservatives") to get re-elected, even with an Über-F'ed up Nobel "Society" bestowing accolades upon Algore for his fiction, only a third of the scientific types accessing the infamous 97% survey responded. The rest were busy - DOING A JOB. Hows the old math mind? Are you capable of subtracting 97% (round to 100%) of 1/3 from 100%? Two -thirds of those given the query (Most likely, those even given the query were presumed to be sympethetic to the cause) think it's BS or not important enough to bother.
What does that say? Well, to someone with a brain that didn't have the synapses singed in their youth, it means that 2/3 of the scientic types that found that questionnaire on their desk round filed it or misplaced it.
"Scientific societies"... Do you realize that translates to "student body" or "idealist young people" huddling around the occasional academic professional (Those who have NEVER held a real job)? Jeez - The coup de grâce has been dealt to end the suffering of this topic hundreds of times - only to be resurrected by two people (Troy and Bos) I suppose, at this point, to try and save face by getting the last words. It's been, what, fifteen(?) years since any measured global warming, anthropogenic or not. Is everyone going to have to be dead and gone before this thread stays buried? It ain't Easter any more. Kind of a tough time for you'all anyway - Hard finding cruelty-free eggs, gluten-free chocolate bunnies, and free-range ham.

 

dskira,

Would you please refrain from posting photos of ************ snow sculptures?

That kind of crude display has no place at a forum of this sort. It disrespects the other people here and shows no self-respect on your own part.

Thank you.