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Losing time, not buying time

Filed under: — raypierre @ 6 December 2010

Control of methane, soot, and other short-lived climate-forcing agents has often been described as a cheap way to "buy time" to get carbon dioxide emissions under control. But is it really?

Expectations for the outcome of the Cancun climate talks seem to be running low, and the suggestion has emerged that maybe we should forget about controlling CO2 emissions for now, and instead do something with short lived climate forcing agents like methane or soot. This is often described as "buying time" to put CO2 emissions controls into place. For example, in a recent New York Times Op-Ed, Ramanathan and Victor write:

"Reducing soot and the other short-lived pollutants would not stop global warming, but it would buy time, perhaps a few decades, for the world to put in place more costly efforts to regulate carbon dioxide." — Ramanathan and Victor

The idea that aggressive early action to control short-lived climate forcing "buys time" to do something about CO2 has often been pushed in the past, e.g. in various newsletters and press releases associated with the UNEP Atmospheric Brown Cloud program, for example

"The BC reduction proposal is not proposed as an alternative to CO2 reduction. At best, it is a short term measure to buy a decade or two of time for implementing CO2 emission reduction strategies." — Ramanathan, writing in the UNEP Black Carbon Newsletter.

To be fair, it should be acknowledged that such pleas for more attention to short-lived climate forcing are almost invariably accompanied by a salutary reminder that it is really CO2 that needs to be gotten under control, as in the quote above. Achim Steiner, writing in the same issue of the Black Carbon Newsletter writes "Paying attention to black carbon should not distract people from the real issue at hand, carbon dioxide." A similar sentiment is expressed in the Ramanathan and Victor op-ed. While emphasizing the central importance of CO2, Penner et al. argue that "…to provide short-term relief from climate warming, the short-lived compounds that induce warming need to be brought under control within a timescale of a few decades." (They also make the intriguing suggestion that doing so might provide a global experiment that could help constrain climate sensitivity.) Writing in Science, Stacy Jackson concludes that "… a focus on CO2 may prove ineffective in the near term without comparable attention to pollutants with shorter lifetimes"

All of this is well-intentioned stuff, none of it denies the central importance of CO2, and I’m sure there are many benefits to be had from reducing soot emissions sooner rather than later. Given the large agricultural component of methane emissions, keeping these emissions from growing in the face of a the need to feed a growing number of people is a serious challenge that must ultimately be met. But still, these proposals tend to convey the impression that dealing with the short-lived forcings now will in some way make it easier to deal with CO2 later, and that’s wrong. In this post, I will explain why.

To get a feel for the issues in play, we’ll first take a look at methane vs CO2. This provides a clean example, because methane has a straightforward, well-characterized warming effect which is easy to compare with that of CO2. If you’re just looking at the concentration of methane and CO2 at a given time, the methane/ CO2 equivalence is pretty easy to figure, since you can turn them both into the common currency of top-of-atmosphere radiative forcing. For example, doubling CO2 from 300 ppm to 600 ppm yields a clear-sky radiative forcing of 4.5 W/m2. Doubling methane from 1ppm to 2 ppm yields a radiative forcing of 0.8 W/m2, but since we started from such a low concentration of methane, it takes many fewer molecules of methane to double methane than to double CO2. Per molecule added, methane yields about 54 times as much radiative forcing as CO2. Note that most of this effect has nothing much to do with any special property of methane, but arises simply because the radiative forcing for most greenhouse gases is logarithmic in concentration, so you sort of get the same radiative forcing for everybody upon doubling their concentration — but if you start with somebody whose concentration is low, it takes many fewer molecules to double. That means that the CO2 equivalent of methane depends on what concentration you are starting with. If you started from a concentration of 10ppm, then the equivalence factor drops to 10. If you start out with equal amounts of methane and CO2 (300 ppm), then the equivalence factor drops further to 0.5. In that sense, methane is, intrinsically speaking, a worse greenhouse gas than CO2, though the crossover is at values that are so high they are only relevant (at most) to the Early Earth. ( I ran these calculations with the Python interface to the NCAR radiation model, provided in the Chapter 4 scripts of my book, Principles of Planetary Climate. They are done using an idealized clear-sky atmospheric profile, so the numbers are a bit different from what you’ll find in the IPCC reports, but it’s nice to have a calculation simple enough you can re-do it yourself.)

Things get a lot trickier when you try to bring time into the problem, because methane and CO2 have vastly different atmospheric lifetimes. Methane oxidizes to CO2 in about 10 years, and since we are dealing with so little methane, that extra ppm of CO2 you get after it oxidizes adds little ongoing warming. That means that the methane concentration in the atmosphere is determined by the methane emission rate averaged over the previous ten years, and the methane component of warming disappears quickly after emissions cease. In contrast, about half of CO2 emitted disappears into the ocean fairly quickly, while the other half stays in the atmosphere for thousands of years. Therefore, the atmospheric burden of CO2 in any given year is determined by the cumulative emissions going back to the beginning of the Industrial Revolution, and the warming persists for thousands of years after emissions cease. Over the long term, CO2 accumulates in the atmosphere, like mercury in the body of a fish, whereas methane does not. For this reason, it is the CO2 emissions, and the CO2 emissions alone, that determine the climate that humanity will need to live with for a time that stretches into the future at least as long as the time since the founding of the first Sumerian cities stretches into the past. The usual wimpy statement that CO2 stays in the air for "centuries" doesn’t begin to convey the far-reaching consequences of the amount of CO2 we decide to pump out in the coming several decades.

As a reminder of that, here’s a graph from the NRC Climate Stabilization Targets report (of which I was an author) summarizing how cumulative carbon emissions set the climate thermostat for the next 8000 years and more.
NRC Cumulative Carbon effect on Climate
The numbers on each curve gives the total cumulative carbon emissions (in gigatonnes) during the time when human activities continue to emit carbon. These results are based on calculations by Eby et al using the UVIC coupled carbon/climate model, and they are really just a reprise of what Dave Archer has been telling all of us for years (e.g here, here and here). It turns out that it matters little to temperature whether all the CO2 is emitted in a carbon orgy near the beginning of the fossil fuel era, or spread out over a few hundred years. It’s cumulative carbon that counts, and pretty much it is the only thing that counts. A cumulative emission of a trillion tonnes of carbon just might keep the Earth below a warming of 2ºC, in line with earlier estimates equating the European Union target warming threshold with cumulative carbon (see our Trillion Tonne post). The peak warming scales approximately linearly with cumulative emissions, and the warming you get at the peak is pretty nearly the warming you are stuck with for the next millennium, with only slight declines beyond that. We are currently about halfway to our first trillion tonnes, but given the miracles of exponential growth, we are going to get there pretty quickly if nothing changes. If you go beyond, and dump 2355 gigatonnes into the atmosphere before kicking the fossil fuel habit, then the global mean temperature will still be 3ºC warmer than pre-industrial in the year 8000. That gives plenty of time for bad stuff to happen, including deglaciation of Greenland, loss of the West Antarctic Ice Sheet, or a destabilizing PETM-type soil carbon release. Note further that these calculations were done with a model designed to have a climate sensitivity similar to the IPCC median. Therefore, even if you hold the line at a trillion tonnes, there is still about a 50% chance that warming will exceed 2ºC.

Let’s suppose, however, that we decide to go all-out on methane, and not do anything serious about CO2 for another 30 years. To keep the example simple, we’ll think of a world in which methane and CO2 are the only anthropogenic climate forcing agents. Suppose we are outrageously successful, and knock down anthropogenic methane emissions to zero, which would knock back atmospheric methane to a pre-industrial concentration of around 0.8 ppm. This yields a one-time reduction of radiative forcing of about 0.9W/m2. Because we’re dealing with fairly short-term influences which haven’t had time to involve the deep ocean, we translate this into a cooling using the median transient climate sensitivity from Table 3.1 in the NRC Climate Stabilization Targets report, rather than the higher equilibrium sensitivity. This gives us a one-time cooling of 0.4ºC. The notion of "buying time" comes from the idea that by taking out this increment of warming, you can go on emitting CO2 for longer before hitting a 2 degree danger threshold. The problem is that, once you hit that threshold with CO2, you are stuck there essentially forever, since you can’t "unemit" the CO2 with any known scalable economically feasible technology.

While we are "buying" (or frittering away) time dealing with methane, fossil-fuel CO2 emission rate, and hence cumulative emissions, continue rising at the rate of 3% per year, as they have done since 1900. By 2040, we have put another 573 gigatonnes of carbon into the atmosphere, bringing the cumulative fossil fuel total up to 965 gigatonnes. By controlling methane you have indeed kept the warming in 2040 from broaching the 2C limit, but what happens then? In order to keep the cumulative emissions below the 1 trillion tonne limit, you are faced with the daunting task of bringing the emissions rate (which by 2040 has grown to 22 gigatonnes per year) all the way to zero almost immediately. That wasn’t very helpful, was it? At that point, you’d probably like to return the time you bought and get a refund (but sorry, no refunds on sale items). More realistically, by the time you managed to halt emissions growth and bring it down to nearly zero, another half trillion tonnes or so would have accumulated in the atmosphere, committing the Earth to a yet higher level of long-term warming.

Suppose instead that you had focused all efforts on reducing the growth rate of CO2 emissions from 3% to 2%, averaged over 2010-2040, forgetting about methane until the end of that period. In this scenario, the cumulative carbon emitted up to 2040 is only 713 gigatonnes, giving more time to avoid hitting the trillion-tonne threshold. The warming from CO2 in 2040 is about 1.2C, but we have to add in another 0.4ºC because we haven’t done anything to bring down methane emissions. That brings the warming to 1.6C, which will increase further beyond 2040 as the cumulative carbon emissions approach a trillion tonnes. However, since methane responds within a decade to emissions reductions, we still get the full climate benefit of reducing methane even if the actions are deferred to 2040. The same cannot be said for deferral of action on CO2 emissions.

The following cartoon, loosely based on Eby’s calculations shows two illustrative scenarios: one in which early action is taken on methane, at the expense of allowing cumulative CO2-carbon emissions to rise to around 1.7 trillion tonnes, and another in which action on methane is delayed until 2040, allowing cumulative emissions to be held to a trillion tonnes. The curves can be diddled a bit depending on how much short term warming you get from controlling additional short-lived gases, and how much extra cumulative carbon emissions you assume goes along, but it is really hard to come up with any scenario where you come out ahead from acting early on the short-lived forcings instead of going all-out to reduce the rate of CO2 emissions.

There are a few greenhouse gases other than CO2 that have lifetimes sufficiently long to lend some urgency to their control. That would include HFC23 with a lifetime of 260 years, CFC13 with a lifetime of 640 years and SF6 with a practically unlimited lifetime. Most of the rest are more like methane than they are like CO2 (e.g HFC31 at 5 years)

Absorbing aerosols — soot, loosely speaking — have a number of complex regional effects that make it difficult to treat their climate impact on an equal footing with that of well-mixed greenhouse gases. Soot falling on snow or ice has an unambiguous warming effect, manifest particularly strongly at high latitudes and high altitudes. For airborne absorbing aerosols, though, it is hard to even know whether they have a warming or cooling effect on surface temperature, or leave it more or less unchanged. Except over high albedo surfaces, airborne aerosols mainly heat the atmosphere by direct solar absorption, at the expense of reduced solar absorption at the surface. When the shading is not too strong, the main consequence is a reduction of the convection that would ordinarily carry solar energy from the ground to the atmosphere. This profoundly influences precipitation, and the atmospheric circulation, especially in the tropics. In extreme cases, the atmospheric absorption can even shut down convection completely, leading to stabilization of the tropospheric lapse rate and a severe surface cooling, as in the Nuclear Winter limit (see also the more elementary discussion of this limit in Chapter 4 of Principles of Planetary Climate).

A further consideration is that most activities that emit soot also emit precursors to reflecting aerosols which cool the planet. It is unlikely (and probably undesirable) that one would be able to limit one without also limiting the other. Hence, the net implication of the black carbon component is probably that it will help offset some of the warming caused by eliminating sulfate aerosols. That’s good, but it’s not what you bargained for if you were expecting a cooling for your money. The main thing about soot and the stew of toxic emissions going into the Atmospheric Brown Cloud , though, is that there are compelling human health, agricultural, and regional climate reasons to eliminate them, regardless of the side effect on global temperature. These are things that need to be done regardless of the climate implications (positive or negative), just as there is a need to supply the developing world with reliable clean water. It is pointless to make an already complicated climate negotiation yet more complicated by wrapping such things into the mix. It is nonetheless worth noting that many of the things one would do to reduce soot emissions, such as substituting natural gas for coal, or burning coal in cleaner, more efficient power plants, also would tend to reduce CO2 emissions, and such double-wins are of course to be sought and pursued ardently (note Gavin’s op-ed on co-benefits of CO2 reduction).

IPCC-style Global Warming Potentials attempt to trade off radiative forcing against lifetime in a Procrustean attempt to boil all climate forcings down to a single handy-dandy number that can be used in climate treaties and national legislation. In reality, aerosol-forming emissions, short-lived greenhouse gas emissions, and CO2 emissions are separate dials, controlling very different aspects of the Earth’s climate future. CO2 emissions play a distinguished role, because they ratchet up the Earth’s thermostat. It’s a dial you can turn up, but you can’t turn it back down. CO2 is a genie you can’t put back in the bottle. Climate forcings should not be aggregated. Each category should be treated in its own right. Otherwise, there are perverse incentives to do too much too soon on short-lived forcings and too little too late on CO2.

379 Responses to “Losing time, not buying time”

  1. 151
    Edward Greisch says:

    Andy Revkin is hassling the word “unequivocal” in the IPCC report in 2 dotearth articles:

    Mr. Revkin claims that the first use of “unequivocal” was incorrect. My interpretation is that Mr. Revkin’s correction allows for more time wasting. The attack of the denialists is not limited to proposing time-wasting side activities like methane reduction. “Buying time” for them is buying more time in which they can profit from selling coal.

    How should the IPCC wording be decided? It seems to me that the IPCC reports should be worded in such a way as to require immediate action. I am assuming that our survival as a species is everybody’s #1 value. Therefore, the original wording was better. What do you think?

  2. 152
    ccpo says:

    “The problem is that, once you hit that threshold with CO2, you are stuck there essentially forever, since you can’t “unemit” the CO2 with any known scalable economically feasible technology.”

    I beg to differ, at least in part:

    terra preta and re-foresting, particularly edible forests/food forests will also help a great deal. there are other bits we can also do. If we also drop emissions as much as is possible to do, which is a lot, but requires a new paradigm, we can get to negative.

  3. 153
  4. 154
    Martin Vermeer says:

    Dhogaza #136, you don’t get it do you. The good senator wants the RAW data… RAW. Get it now? The measurements without the Stevenson screen…

    (I am reminded of the story, possibly apocryphal, of a Finnish environment minister visiting a sewage treatment plant, who upon hearing that the pH of the affluent was around 7, insisted that that was too much and that an effort should be made to bring it further down…)

  5. 155
    ccpo says:

    GlenFergus says:
    7 December 2010 at 2:42 AM

    this perfect storm is just getting more and more perfect

    Seem so RP. If there is some (slight) hope, perhaps it lies in what Aleklett’s group and others are saying about resource limits. E.g., in the first graph above, is there 4000 Gt of realistically extractable carbon to emit? They appear to think not.


    Aleklett is wedded to his outcome. I have been round and round with him on this and he never budges regardless of the logical explanations, etc. It is his stated policy and intent to ignore any science that is post-IPCC IV. Talk about a massive cherry pick!

    The result of this intentional and self-inflicted blinkering is that he cannot properly address the potential outcomes of additional emissions… because he simply dismisses that they matter.

    But let us first look at Kjell’s assumptions. Well, that’s the problem, they’re assumptions. He treats his group’s estimates like they are facts when they are not, then draws the conclusion from his fallacious assumptions. To wit, he says we have a lot less coal than most think, so the worst case scenarios can’t happen. OK, let’s say he’s right. The problem with this is we can be sure we have about the same amount of fossil fuels yet to burn as we have burned, even if we don’t have as much as some think. We have raised CO2 by 105 ppm and will raise it another 105 if we burn the rest. That takes us to 500 ppm. But, hey, don’t worry! All post-IPCC IV climate science doesn’t exist until it is published in IPCC V!

    Even worse, he simply pretends that 3C is the official, not-to-be-discussed reality when it comes to sensitivity even as articles published even here place it as high as 4.5C or more, if memory serves.

    Research such as that on methane emissions and that showing Greenland possibly can melt away at as low as 400 ppm are completely ignored. 350? Not in IPCC IV. Arctic sea ice, thermokarst lakes, methane emissions, Antarctic melt… all fantasy until IPCC V.

    I am one who understands and accepts the implications of Peak Oil. Aleklett is the worst kind of Peakist because he is too devoted to PO and seems to need it to be THE issue of the day. He does not understand or care about tipping points in the climate system and does not understand the massive risk being taken in allowing CO2 500+. His failure to understand tipping points prevents him from understanding that the effective time period for dealing with them is before they have happened. Given the observations of climate we have all around us, the probability we have passed or are about to pass tipping points is far too high, yet Aleklett fails to see that if this is so, then AGW and PO are actually happening at the same time and must be dealt with now.

  6. 156
    David Painter says:

    re 125
    “This is a very nice example of a useful ‘visual’ to use when explaining mixing in the atmosphere”

    Whilst observing a CO2 exhibit @Bristol (uk)(warm tank with dry Ice dropped into it) the vaporised CO2 forms jets and wave fronts that displace the surrounding volume of air until mixed. (causing vectored motion of the body)By observing METEOSAT Vapor bands and other satellite images of volcanoes, gas fields and biomass sites this effect is demonstrably visible.

    When combined with the Infra-red bands of the satellite it seems these displacements exist in the infra-red wavelengths as well (have images), indicating that at the source of an oil fire,volcano, biomass burning a “front” will spread out from a point. Normal cloud formations are apparently excluded from these regions in some case for quite a considerable time (weeks). From my own observations low level continuous release by higher altitude sources such as aircraft and high altitude sites this effect appears longer lasting (greenland).

    So the response “Location of soot and other aerosol emissions is important, but CO2 can be considered (for purposes of radiative forcing) well mixed on account of its long lifetime. It doesn’t matter where the CO2 is emitted.”

    I find curious, as the volume of expanding gases from a volcano/gas field takes weeks to “mix” to a uniform level, meanwhile it has a more definable effect that appears ignored(?) Energetic sources of CO2 injected to higher altitude (gas flares, aircraft, volcanoes) are further away from carbon sinks and lower dynamic mixing effects so surely longer lasting and therefore cause more longterm effects? If CO2 can exist for approx 100yrs in the higher atmosphere a small level there can cause more warming than a large level at sea level surely?

    Appreciate informed engagement

  7. 157
    Hugh Laue says:

    #153 Blair Macdonald
    website of the Biophysical Economics Workgroup, a community that seeks to advance a new paradigm in understanding economic systems.

    Grounded in the real world.

  8. 158
    Alan of Oz says:

    The death of the coal industry is inevitable, it should be put out of it’s misery before it takes the rest of us along for the ride. A global moritorium on new coal plants is not unreasonable, it’s essential.

  9. 159
    Ray Ladbury says:

    I used to live in coal country, and my experience of the miners tended toward the opposite coecnclusion. A lot of miners became fascinated with the fossils and some of them as a result rejected Young-Earth Creationism (though not religion or even fundamentalism, necessarily). A lot of these guys were pretty smart–they’d just never had any education.

  10. 160
    CM says:

    Ed #151, my five cents is that Revkin did a good job spotting that, and spared us at least one round of time-wasting “Cancungate” idiocy down the road.

  11. 161
    E.L. says:


    I would like to offer a criticism on this topic:

    “Expectations for the outcome of the Cancun climate talks seem to be running low, and the suggestion has emerged that maybe we should forget about controlling CO2 emissions for now, and instead do something with short lived climate forcing agents like methane or soot.”

    The main problem with the idea of “controlling CO2 emissions” is economic reality. Nations are not going to go along with the idea of controlling emissions because they are at competition with each other in cut throat markets, and energy production is an essential tool for competition. A nation would be quite worried about getting cut out of the market place if it went along with any kind of ‘controlling CO2′ emissions plan.

    In addition, the idea of allowing developing nations an exemption for CO2 emissions is simply a mistake. Today, we live in a world of globalization where businesses can produce in any nation. Investment, production, and CO2 emissions would only change locations instead of being reduced. But at the same time, developing nations are not going to go along with CO2 caps because they want to become developed and productive. All in all, the idea of controlling CO2 emissions is a failed strategy.

    [There is a lot of low-hanging fruit in power plant energy efficiency, and in end-user energy efficiency. --raypierre]

    Although becoming more energy efficient could be desirable from an economic standpoint, I don’t see how it could help with CO2 reduction. More efficiency would almost certainly lower prices, and the consumption of energy would change.

    Instead of trying to ‘control CO2 emissions’, the world needs to focus on replacing the technology that requires CO2. A reduction of CO2 emissions requires innovation instead of stagnation. If funding of research is a problem, the negotiations at the climate talks should center on funding instead of controlling emissions. Nations may be more willing to write a check.

  12. 162
    M says:

    “A reasonable person wouldn’t get hung up on that. ”

    Ah. Yes. Perhaps my problem is I spend too much time dealing with what unreasonable people think, and so am making my own language excessively complicated in order to preemptively defend it from those people…

  13. 163
    Radge Havers says:

    Edward Greisch 151
    CM 160

    OK. So IMAO, Revkin doth protest too much.

    How it reads to me:

    Very likely. As in, “Yes, yes, my little dears, if you listen very carefully you will very likely hear the prancing of little hooves on the rooftop Christmas eve.”

    Now maybe “unequivocal” is too strong for timid scientists who grew up having the pocket protectors kicked out them at recess. So how about “most probable”? If not that, what wording would most accurately reflect what we can say about physical reality over the babbling of surreal politics? That’s really the issue right?

    So narrate already.

  14. 164
    Didactylos says:

    Shorter Blair Macdonald:

    An acid trip view of CO2

  15. 165
    David Miller says:

    EL, to paraphrase Ray Ladbury before, what do you think happens when economic reality meets up with physical reality?

    Although becoming more energy efficient could be desirable from an economic standpoint, I don’t see how it could help with CO2 reduction. More efficiency would almost certainly lower prices, and the consumption of energy would change.

    Jevons paradox isn’t an immutable law of nature you know..

    This is just weird:

    Instead of trying to ‘control CO2 emissions’, the world needs to focus on replacing the technology that requires CO2.

    How, exactly, do you propose to control CO2 without replacing the technology that require it or increasing efficiency?

  16. 166
    CRS, Dr.P.H. says:

    Gavin, I fully support moving for environmental controls of methane (fossil or biogenic) immediately while we continue to build the case for carbon dioxide reduction.

    I’ve been designing & building anaerobic digesters (methane producing wastewater plants) for over 25 years, and only recently has this technology come into widespread usage. Cargill makes extensive use of these, and my own project for a ConAgra potato plant has won numerous awards including Sierra Club & Trout Unlimited recognition.

    EPA is adding pressure on US power generators via the “Prevention of Significant Deterioration” and tailoring approach, so we will see progress towards CO2 reduction from this understated driver. Utilities will switch to natural gas & improve efficiency, which will help a great deal. I’m doing work in this area presently.

    Sadly, we have virtually no control over China, India etc., so a massive push by the USA into carbon dioxide reduction will hurt us economically, and this is just not politically viable. We would be better off to gather “low hanging fruit” with tax incentives & credits, improve the natural gas pipeline/leakage problems as has been mentioned, and do other biogenic methane mitigation steps.

    In the meantime, new technologies will come to the forefront, and the US government should incentivize the development of these. I have one patent pending that might be part of the puzzle, but getting the capital to develop this stuff is amazingly difficult.

  17. 167
    Brent Hoare says:

    I regret not joining the discussion earlier, and sorry for the length of this post, but as one of the few participants in the climate debate focussed on the contribution of halocarbons to AGW emissions, I’m both puzzled and frustrated at the lack of attention thus far on the role of CFCs, HCFCs and HFCs in driving climate change. The combined contribution of these gases to radiative forcing is greater than NO2, and second only to methane in importance, after CO2, yet they seem to have only a tiny amount of attention in the policy debate, yet they are among the easiest and cheapest sources of emissions to address. The NYT op ed at least did something to address this, and along with the Consumer Goods Forum announcement on day 1 of Cancun that the global fast mooching consumer goods industry want to be HFC free by 2015 (or thereabouts…) the early signs that we might see some action on F-gases were looking good.

    Before going any further, I have to confess that I have been guilty of repeating the line that efforts to reduce F-gas emissions will achieve fast acting climate change mitigation, that would help to “buy time” to address the much more difficult, expensive and seemingly intractable problem of reducing CO2 emissions. I’m extremely grateful to Ray Pierre for so lucidly exposing this as attention grabbing spin, that is not supported by the science. I promise not to do this again, and to draw this to the attention of others, though in my defence I’ve never urged action on F-gases as a substitute for CO2 emission reductions, and have never doubted that this is the main game – but surely the task we face is so daunting that we need to use all the tools at our disposal, and the 7% increase in HFCs (10% for HFC134a) recently reported by the Scientific Assessment Panel of the Montreal Protocol ought to be cause for great alarm?

    With the greatest respect, doesn’t the seriousness of the climate threat posed by the ‘super greenhouse gases’ deserve more discussion than the single paragraph: “There are a few greenhouse gases other than CO2 that have lifetimes sufficiently long to lend some urgency to their control. That would include HFC23 with a lifetime of 260 years, CFC13 with a lifetime of 640 years and SF6 with a practically unlimited lifetime. Most of the rest are more like methane than they are like CO2 (e.g HFC31 at 5 years)”. (For instance, a bitter debate rages over the mis-spent CDM funding for HFC23 destruction, a by-product of production of HCFC22, and environmental advocates could really do with some help from those in the scientific community who understand what a big deal this is…)

    As the ESPERE article linked to states, HCFCs “still act as strong greenhouse gases in the troposphere and so can be regarded as a compromise but not the best solution to the problem” – and some increasingly popular blends (eg R-404a and R-410a) of HFCs have even higher GWP than the HCFC R-22 now being subjected to an accelerated phase out due to the recognition of this fact by the Parties to the Montreal Protocol (btw – the GWP values give in this article are now outdated, and have been significantly increased by AR4, and the use of 100 yr GWP in most cases significantly understates the climate impact of these gases, the 20 year figure being a much more realistic measure, but this is another issue!).

    Tragically, the HCFC/HFC compromise delivered by the Montreal Protocol to address CFCs in the 1990s was at the time largely unnecessary, and today is completely so – natural refrigerants, including ammonia, CO2 and hydrocarbons, along with other innovative solutions, are certainly up to the task of meeting the world’s refrigeration and air-conditioning needs, although this is much more accepted in Europe than in the US (and we need all the help we can get to change this very unfortunate situation…).

    Surely the most significant point is that even for relatively short lived gases like HCFC22 or HFC134a, every kg we release to atmosphere means we would have to remove (depending on how you measure it) an additional 1.4 to 5 tonnes of CO2 in the next decade or two, if we wanted to compensate for the radiative forcing impact of these Potent Industrial Greenhouse Gases (PIGGs – my favourite term for them).

    So accepting it’s incorrect to claim that F-gas emission reductions “buy time”, is it not true that reversing the rapid growth of HCFCs and particularly HFCs could save us from a lot of completely unnecessary “heavy lifting” (or some other more appropriate metaphor) in future, in order to keep average temperatures below any particular threshold (not to mention the huge banks of much more potent CFCs, and HCFCs leaking from ‘banks’ of existing equipment around the world, while endless and largely ignored debate takes place in Montreal Protocol meetings, and the fluorolobby pretends their pathetic existing recovery and destruction schemes are working…)?

    Credible projections of HFC atmospheric concentrations over coming decades that assume developing countries follow the high GWP HFC path we have been led down by the fluorolobby indicate alarming increases in their contribution to radiative forcing – from less than 2% now (from nothing 20 years ago!) to upwards of 9%, 20% or 45% depending, inter alia, on assumptions about the success of CO2 mitigation.

    In the next few years we could choose to go down a genuinely climate friendly natural refrigerant solutions path, but the chances of success in this up till now obscure backwater of the global warming debate would be vastly improved by stronger calls for action on F-gases from the scientific community.

  18. 168
    Brent Hoare says:

    PS – in response to the comments above, use of natural refrigerants is one of the best ways to improve energy efficiency in the RAC sector, and there are really exciting innovations occurring in the solar cooling field, for both refrigeration and air conditioning. Already there are commercially available AC systems running on solar panels that provide free hot water too, and competing products are expected to come to market next year.

  19. 169
    Brian Dodge says:

    “The missing numbers are how much this would cost per kWhr.”
    “Starting next month, the plant will produce 3 megawatts of electricity. One megawatt is enough to power 5,000 homes as a continuous power source.
    The plant captures methane produced by decomposing garbage buried at the landfill. Generators then convert the gas into useable electricity.
    The electricity is fed into the power grid and sold to interested customers, Loehr said. ”
    Charleston has a population of ~50,000, and ~22,000 households, so this plant will provide ~20% of their electricity[1]. According to news reports, it cost ~$6 million, or about $1200 per household. TARP is $700 billion; US population is 330 million, in 127 million households, so TARP is ~$5500 per household.
    This plant will generate >$600,000 worth of electricity per year if sold at a wholesale rate of 2.5 cents per kWh, or a 10% return on the investment. The actual financials may or may not be released subsequent to a FOIA request to the WV Public Service Commission.

    [1] There is a bookkeeping myth that the electricity from this plant will only be sold wholesale to industrial consumers, so they don’t have to go through a bunch of public utility paperwork about regulated consumer electric rates. They will be pumping their electrons through the same pipes (existing utility transmission line infrastructure) that supply everybody – wholesale, retail, industrial, consumer, government, etc.

  20. 170

    FYI – I will be at AGU. If anyone wants to meet you can reach me via my contact form and I will send you my mobile #.

    I’ll be on the road for the next three days and arrive in SF on Sunday. I will also have a poster in Moscone south on Thursday.

  21. 171

    BTW – If anyone needs a poster service, I found one in Redwood City. 48″ x 72″ for $120 and free delivery to your hotel or Moscone Center. I think he said he can turn it around in 24 hours also.

    I have not used the service before so I can’t say much else. But since I’m a bit behind this week, if it works, it will prove to be a wonderful thing.

    Especially since the airline I’m flying told me it would cost an arm and a leg to take a poster on the plane (size makes it extra luggage).

  22. 172
    E.L. says:

    David Miller: EL, to paraphrase Ray Ladbury before, what do you think happens when economic reality meets up with physical reality?

    Markets will make adjustments as they do during boom bust cycles.

    David Miller: Jevons paradox isn’t an immutable law of nature you know..

    Honestly, I’ve never heard of Jevon’s paradox until I read your comment. I’m surprised that someone even considers it paradoxical. I think it makes perfect sense.

    David Miller: How, exactly, do you propose to control CO2 without replacing the technology that require it or increasing efficiency?

    Perhaps you should re-read my comment. I said the focus should be on replacing the technology instead of trying to make it clean or controlling emissions.

  23. 173

    EL 161: The main problem with the idea of “controlling CO2 emissions” is economic reality. Nations are not going to go along with the idea of controlling emissions because they are at competition with each other in cut throat markets, and energy production is an essential tool for competition. A nation would be quite worried about getting cut out of the market place if it went along with any kind of ‘controlling CO2′ emissions plan.

    BPL: Then we’re all dead.

  24. 174
    David says:

    Ray – this is an excellent post and very helpful and timely. I would like to point out that there is another benefit for reducing SLCFs, using the example of BC in the Arctic – by reducing the overall positive forcing as well as the albedo effect, reduction of BC could have tangible positive short term effects on Artic climate. For example, perhaps more multi-year sea ice would survive over the summer melt season if BC were reduced. In this case, CO2 forcing might have a somewhat less severe effect on sea ice. This doesn’t buy time in the sense of limiting the CO2-induced peak warming and its duration, but it holds out the possibility of somewhat lessening the immediate damage to the Arctic while efforts to stabalize long-lived GHGs are undertaken.

  25. 175

    168 Brian Dodge

    There are still some missing numbers.

    Up front costs to build stuff are not free money. Operation costs are not free money.

    And any electricity put on the grid is the same as any other and merges according to the impedances of the electric circuits involved. Anything paid for electricity is a result of complex market price determination and basically, the cost is whatever it costs to fill the loads at any given time. It is conceivable that the methane could be stored and used to power peaking generators, and in that circumstance the feed in tarif should be quite high.

    Do you suppose the municipal folks have figured that out?

    But the other missing numbers are how much it actually costs to run such a thing, and would 5000 homes be a meaningful part of the community of homes needed to run such a plant. What do you suppose? 1% or so?

    If all the numbers make sense, have at it. But please stay out of the way of real actions. And try not to tell people that every little bit counts, in some important way.

  26. 176

    I thought the thread was methane and our host, raypierre, told us it was not worth bothering about.

    Someone here quoted that same host as saying something about low hanging fruit. Who can argue with that, except that what seems to be low hanging often turns out to be not so low when costs get correctly considered. Again, if it makes sense, have at it.

    But you need big thinking such as I offer if you really care about fixing the problem. Massive standing forests will indeed take up CO2 and hold it as organic compounds, yes, permanently if correctly managed. And the local critics went wild if this fell short of capturing the entire CO2 output of coal fired power plants. Cost is of course an issue in this, but it does seem that there is a potential enterprise value in the whole thing that could be reasonable.

    [Response: Your host emphasizes that methane needs to be dealt with eventually, especially given the likely growth of agricultural sources. The point is that given a choice of which to do first, it's CO2 that wins hands down. By the way, your host will soon need to bow out of active responses, in order to make time to get ready for AGU, and then Christmas preparations. I hope you enjoy continuing the discussion, and I really appreciate it that everybody has stayed pretty much on-topic. --raypierre]

  27. 177

    raypierre at 137

    Thanks for responding. I failed however, to adequately state my questions.

    As I continue to distill the references, as I have been doing for some time, it seems that the heart of the matter is how fast CO2 can go into the deep ocean.

    It seems that everyone accepts the Revelle result (Scripps 1960s) that the deep ocean water is extremely old, so the overturning circulation is exceedingly slow. Thus, even though at great pressure and low temperature, CO2 would be held in solution in massive quantities, it will not get there in a meaningful time frame.

    I read a description of the Revelle method and am amazed at the credibility given this technique. It assumes that a sample of water is a capturing of a fixed collection of molecules that has hung together for thousands of years, and has not been corrupted in all that time by sources of carbon dioxide other than the atmosphere, some of which could be via the consumption of oil by bacteria which would drastically bias the results toward the very old end of the scale.

    There also seems to be consensus that overturning currents operate only near the poles, and yet this ignores a variety of mechanisms that might operate slowly, but would not require the delivery system of the thermohaline circulation into the deep ocean. Notice, I leave the term deep with inexact definition, and indeed my question is inexact having the intention of exploring the subject, not pronouncing anything with finality.

    I particularly point to the seasonal variations over much of the ocean surface that function somewhat like the vertical pumping that is acknowledged at the poles. It is a fact* that there is an alternating condition from a vertically mixed layer and a pronounced thermocline. The processing driving this being both sun heating and wind cooling both cause increase in salinity. As soon as the vertical mixed layer sets in, the more saline upper water should mix downwards, just as it happens at the poles. The point is of course that this vertical mixing would seem to cause both heat and CO2 to move downwards, being carried by the more saline water.

    I hasten to add that this process would not negate the threat of global warming, but it could impact the rate, and as you say, the negative curvature having been canceled, this might return some of that negative curvature.

    *Though it has been received here with scorn by some, I have no hesitation about relying on the accumulated data of the underwater sound world to assert that this is the case.

  28. 178
    John Mashey says:

    1) A large component of human wealth is:
    work = energy * efficiency

    as per Ayres. Given that we already ~peak Oil, and will likely see peak gas this century, and maybe Peak Coal, the total world use of fossil energy will decrease, even ignoring the climate issues. See p.34 of the Ayres piece for modeled US GDP trajectories under different efficiency assumptions.

    Pick a given level of total emissions, as per Ray. One can assume that most recoverable oil&gas will get used, with the big variable being how much coal stays in the ground.

    Now, what’s the temporal distribution of those emissions?
    The two extremes are:

    1) Use it up as fast as possible (“Drill here, drill now”) and do everything possible to avoid investing that energy into efficiency improvements and non-fossil energy infrastructure.

    2) View the remaining fossil fuel (within the total budget) to be a precious resource to be carefully used, so that when its usage as fuel falls to some relatively small level, the replacement infrastructure gives a smooth transition, not a sudden crash. Given the longevity of many energy systems, and the large capital requirements of some, you have to start early when you have the money.

    There is of course a close analog in business: you depend on selling product X, but it is guaranteed that the volume of X will start decreasing. At some point, you had better be investing profits from X into developing new product Y, because if you wait until X sales really start dropping, it may be too late and you go out of business.

  29. 179
    Joseph Sobry says:

    I agree essentially with what you’re saying Jim (@145). Except that perhaps you did not read the GlobeandMail/Steve Forbes article pointed to by ScepticMatthew. If indeed we will be able to produce a lot more natural gas then we should start shutting down the coal plants now, the dirtiest ones first, and convert to natural gas. As I understand it this is a zero sum game, if the price of NG stays within certain bounds. In fact the utilities may make a profit after the conversion because of it.
    In view of the fact that the (Forbes) article brags about how much more natural gas will be produced then the natural gas price will not be affected by converting from coal to natural gas.
    The other reason I would back up natural gas electrical generation is that, as you point out, it lends itself quite well to co-generation (i.e. get every last calorie out of the stuff and use it wisely) AND it is also easier to do CO2 sequestration per energy unit produced. In addition natural gas is a generally cleaner fuel and cleans up easily at the source even when it has excessive sulfur or CO2 or other contaminants. Thus conversion of coal plants to natural gas will improve public health because we will no longer exhaust some rather dangerous and well documented pollutants that come from ‘clean coal’.
    Ultimately I would like to see all fossil fuel based electrical generation disappear but at my age that is now a pipe dream.
    None of this is really new. If I remember correctly the first and most reasonable request from Mr. Jim Hansen was “No new coal plants without CO2 sequestration”. Since that request was made, I shudder to think how many new ones have been built without any CO2 sequestration. The only half serious attempt I am aware of is the coal pilot plant (30MW) at Schwartze Peipe (literally Black Pipe because of it’s awfully black exhaust smoke stacks) in Germany run by Vattenfall a Swedish utility. But then they are burning very brown and very dirty coal. Even there, the rest of that plant several hundred megawatts worth is still spewing out their awful stuff through their Schwarze Peipe. Convert the whole thing to natural gas, I say.

  30. 180
    Russell says:

    This whole analysis depends on the claim that carbon capture from air is not feasible and will not be for 1000′s of years.

    There is already evidence that it is possible with easily foreseeable technology:

    In order for your claims about future temp to be correct, you need to make the extraordinary claim that not only is Co2 capture from air not possible in large amounts, but this will remain the case for thousands of year, in spite of technological advancement!

    A more accurate assessment of the trade-offs would look at the impacts of this technology. For example in a technologically advanced world it is entirely possible that we will take more Co2 out the air per year than we currently put in.

    [Response: I think intensive research on air capture is justified, and also that even in the best of all possible worlds, air capture will be needed if we are to hope to get rid of the last one or two gigatonnes (C) of annual emissions. But it is foolhardy to bet at present that air capture will become feasible in time to take care of the problem. If you were betting on controlled fusion solving the energy problem, as many were doing fifty years ago, you would have lost big time. A thousand years is a long time for technology to develop, but it also provides a long time for bad stuff to happen, sociopolitically as well as in the climate system. --raypierre]

  31. 181

    180 Russel

    Forests capture CO2 from air as do oceans.

  32. 182

    179 Joseph Sobry

    There is a dilemma in the idea that natural gas can be produced in such volumes that it will not affect the price of natural gas if we use a lot of it. The dilemma is that the amount of natural gas that can be produced depends in the first instance on the market price of that stuff.

    Natural gas reserve estimates are based (by definition) on current market conditions. Thus, when the price was $8 per MMBTU it was worthwhile to spend a lot for equipment and processes to search for and extract that stuff. All of a sudden, there appeared a great abundance. Now that natural gas has fallen to around $4 (last month) half of the rigs were taken off the task of natural gas exploration and put on other jobs. Also, reserve estimates are circular, meaning that the reserves are based on the actual production, but paradoxically, actual production also reduces reserves, so there is some reason to mistrust these estimates. You also might note that a natural gas corporation has a stock price which is directly affected by reserve estimates.

    I suspect that market development efforts were directed at getting us to use as much natural gas as possible, and this might have kept the price up, but marketing did not work the needed magic.

    And by the way, other than ever improving seismic technology, the so called new technology for natural gas exploration is not that new. As near as I can tell it is simply using more harsh chemicals and yet higher fracking pressures, and these are fundamentally problematic activities.

  33. 183

    179 Joseph Sobry

    The things going on in Germany with power production are likely driven more by the worry about depending on Russia for natural gas.

    Mr. Jim Hansen’s request regarding CO2 sequestration is an obvious course of action if such CO2 sequestration was economically feasible. The surprising thing is that he would think it so feasible, given the fundamental contradiction of using a heat engine, whereby expanding gases convert heat to mechanical energy, and then using mechanical energy to compress those gases and to force the CO2 down a hole. True the gases include 12% CO2 but separating these without energy usage is far from simple.

    And whatever the drained energy for CCS is, that must be compensated by roughly three times that in heat by burning more coal.

  34. 184
    Hank Roberts says:

    > Jim B
    > Forests capture CO2 from air as do oceans

    Subtle distinction, already pointed out above:

    Forests capture CO2 from the air with photosynthesis.

    Oceans capture CO2 from the air as the gas dissolves in the water.

  35. 185
    David Painter says:

    The earth has captured Carbon since it’s creation as Sidderite Ore, (FeCO3) much of the fossil record contains iron and carbon like this. Some lab research has been done converting organic matter to Sidderite using microbes. Large scale capture and conversion is a possibility as the planet does this without the aid of technology, is any research being done?

    “This process of the formation of siderite concretions has been replicated in the laboratory. It was found that the time it takes for the gel to form is only about two weeks. Any organic material can precipitate this action ”

    Sidderite is stable, locks up Carbon, forms in the presence of carbon CO2 and uses the most abundant mineral on Earth.

  36. 186
    Hank Roberts says:

    > sidderite

    “siderite” — geomicrobiology.
    Here’s a review article:

    “… siderophores as important agents in promoting mineral dissolution, microbial oxidation of reduced minerals (acid mine drainage and microbial leaching of ores), and microbial reduction of oxidized minerals. Under the second topic, both biologically controlled and induced mineralizations are reviewed with a special focus on microbially induced mineralization (microbial surface mediated mineral precipitation and microbial precipitation of carbonates)….”

    Don’t go wackywoo about abiogenic petroleum without reading references you can find with Google Scholar, though. A recent one:

    “The two theories of abiogenic formation of hydrocarbons, the Russian-Ukrainian theory of deep, abiotic petroleum origins and Thomas Gold’s deep gas theory, have been considered in some detail. … Both theories have been overtaken by the increasingly sophisticated understanding of the modes of formation of hydrocarbon deposits in nature.”

  37. 187

    180 Russel,

    I find it easier to foresee the oceans taking up the CO2. And they are already in place, and possibly doing it as we speak.

    The only thing standing in the way of thinking this, is the carbon dating of deep water by Revelle. Wouldn’t the validity of that carbon dating be worth discussing?

    Hank Roberts,

    I have looked for discussion of this and turn up nothing beyond the Weart discussion which accepts the Revelle result without question.

  38. 188


    “. . .the fundamental contradiction of using a heat engine, whereby expanding gases convert heat to mechanical energy, and then using mechanical energy to compress those gases and to force the CO2 down a hole. True the gases include 12% CO2 but separating these without energy usage is far from simple.”

    Maybe not “simple,” but two groups at least consider it basically solved. One is of course Kilimanjaro Energy, formerly GRT, Klaus Lackner’s company. (Yes, that would be the same Klaus Lackner Raypierre just referred to the other day WRT extractable fossil carbon.) Kilimanjaro has demoed their process, notably at AGU.

    Oops–looking for a link on the agu demo, I found this (which mentions the capitalization of Kilimanjaro a bit about a third of the way down the page) but also a Japanese company which has developed a generally similar process to Kilimanjaro’s:

    A Canadian university group also came up with some promising technology on this question:

    So three groups now (that I know of) have reported significant work on this problem. Kilimanjaro probably has the lead in that they have obtained serious investment and are currently working toward a *commercial* prototype. I’d link their website, but honestly there’s not that much detail there–they like to play things somewhat close to the vest, IMO.

  39. 189

    Hmm, then there’s this report:

    This, too, though there’s nothing on the technological side. But I was unaware of the extent to which South Korea is taking serious mitigation steps–or at least, appears poised to do so.

    (Yes, I’m aware of deep misgivings on CCS generally, and don’t mean to “cheerlead” the technologies. But it’s relevant and interesting to see what is being attempted.)

  40. 190

    OK, here’s the second link, which I neglected to paste into the previous post:

  41. 191

    185 David Painter

    Every calcite shelled creature has captured CO2 in their shells, and much of this is the sand of the world.

    As I am informed here, the CO2 can become excessive and reduce the rate of growth of such creatures, and the old shell material can be acted on by acid and release of CO2 would occur. It seems to me we are a long way from the acid level needed to do this latter action.

  42. 192

    187 Kevin McKinney

    Note I said, ‘without energy usage.”

    The Klaus thing shows heat as an input.

    Then consider the assertion that the CO2 can be a fuel.

    There is of course the cement making process of Caldera (I think its called that) which is promoted by Vinod Khosla. There are serious questions about that also, but it is at least conceivable.

  43. 193
    Patrick 027 says:

    Re 161,172 E.L.
    Instead of trying to ‘control CO2 emissions’, the world needs to focus on replacing the technology that requires CO2. A reduction of CO2 emissions requires innovation instead of stagnation. If funding of research is a problem, the negotiations at the climate talks should center on funding instead of controlling emissions. Nations may be more willing to write a check.

    Great idea. And to be fair, the check should be proportional to CO2eq emissions (with some accounting for past emissions to be fair to nations which thus far have not emitted much, not cut down their forests yet, etc.). Now we have an international emissions tax (which nations could, in their own interest, pass on to emitters they host; they can use tariffs and subsidies to correct for trade between nations with different policies, although the international tax would tend to make this less necessary). The price signal shifts demand from higher to lower emissions-intensive pathways. What if those options aren’t there yet? Well, the thing is, the price signal also acts on investement in supply; fossil fuels will become cheaper as demand pulls away, but they’ll become more expensive as investment pulls away; clean energy and efficiency will do the opposite, but will also tend to come down in cost with technological advancement, market volume, and increasing experience, before hitting the limits of scarcity, while fossil fuels will hit the limits of scarcity and increase in price anyway; plus, there is the price induced by the tax.

    (Point being: 1. a well-designed (or even perhaps just adequately-designed) policy, even if a tax, can spur innovation, not crush it; 2. funds for R&D, if they don’t come from a tax on specific activities responsible for the need for said R&D (and/or adaptation costs), must come from the general tax revenue, which is more of a tax on the ‘(small) businesses’ and ‘the people’ and ‘hard working Americans/Australians/Chinese/etc.’ then the former, as it can’t be escaped by individuals choosing lower-emissions alternatives. Maybe you weren’t trying to argue otherwise, but I wanted to make this point…)

    Jevon’s Paradox – makes sense to me too, but not in the infinitely-powerful negative feedback that some may portray it to be. Specifically, if there is a certain amount of fossil fuel we are willing to pay for now, and then nation A (such as the U.S.) decides to impose policies which reduce it’s consumption, then the price goes down, so that other nations (China) are willing to buy more. But what would happen if Chinese consumption increased enough to erase any global effect? Then, aside from costs of transport, etc, the price would go back to what it was before – but at that price, Chinese consumption was lower. So the global consumption should generally tend to be reduced by voluntary reductions of some people/nations, just not generally/necessarily by as much as the voluntary reductions. (Of course, this is all relative to changes that will occur without any such policy.) Anyway, if climate policies result in increased efficiency without changing emissions, that’s better than nothing – at least we’ll have more wealth available relative to what may need to be expended trying to rapidly breed new crops, irrigate parched lands, build sea walls, and relocate climate change refugees, etc.)

  44. 194
    Hank Roberts says:

    > … much of this is the sand …. It seems to me we are a
    > long way from the acid level … the latter action

    Jim, why proclaim ignorance and belief when you can look this stuff up?
    Would you wait til the beach sand is dissolving to worry about ocean pH??

    Seriously, Google wants to befriend you. You could learn so much that would change what you believe, information that’s easily within reach.
    Limnol. Oceanogr.: Methods 8, 2010, 441–452
    DOI 10:4319/lom.2010.8.441

    “… the rate of change in the physical environment as a result of anthropogenic influence will likely occur faster than biological adaptation or microevolution can occur (see Gienapp et al. 2008; Visser 2008; Bradshaw and Holzapfel 2010). Thus, evolutionary rescue for some species may not be
    an expected outcome (see Bell and Collins 2008).

    … Early life history stages have been a focus of much of the first wave of ocean acidification research, given the central role these stages play in
    maintenance of adult populations via dispersal and recruitment processes (see Kurihara 2008 for a review). The main concern here is that embryonic larval stages may be highly vulnerable ….

    Indeed, accumulating evidence suggests that ….

    … understanding the response of early life history stages to rapidly changing oceanic conditions is indeed a leading research priority for organismal biologists working in marine ecosystems ….”

    ——-end excerpt——

  45. 195
    Hank Roberts says:

    Another feedback:

    “… degradation of polysaccharides, a major component of marine organic matter, by bacterial extracellular enzymes was significantly accelerated during experimental simulation of ocean acidification. …. Our study suggests that a faster bacterial turnover of polysaccharides at lowered ocean pH has the potential to reduce carbon export and to enhance the respiratory CO2 production in the future ocean.”

    definitive version: Biogeosciences 7 (2010): 1615–1624
    As published:

  46. 196
    Maya says:

    Hank, my browser had trouble resolving the aslo link. I found it, but it leaves out the :8081 and says free instead of locked … here is my version, for anyone who had the same problem:

  47. 197

    #192–Jim B.–

    You can’t mean *zero* energy use, or the damn thing would be a perpetual motion machine!

    The point is to use *less* energy to achieve sequestration in order to make it economic–right? That at least is how I read your original comment.

    WRT to “heat as input,” I think you mean the U. Calgary team, not Kilimanjaro. IIRC, Kilimanjaro don’t use heat, but some sort of washing process (still, of course, requiring a non-zero energy input.)

    I’m not sure where the “CO2 is fuel” bit comes from–or do you mean this: “enabling the production of liquid transportation fuels?” If so, the CO2 isn’t fuel itself–the plan is rather to air capture CO2 and use it for oil extraction. The CO2 from the air ends up sequestered in the oil field, offsetting the carbon in the oil (though to what extent, I’m not sure; I’ve never heard numbers as to how much is released versus sequestered.)

  48. 198
    E.L. says:

    BPL: Then we’re all dead.

    People will just have to innovate a solution that is economically viable to compete with CO2 based technologies.

    Patrick 027: “And to be fair, the check should be proportional to CO2eq emissions (with some accounting for past emissions to be fair to nations which thus far have not emitted much, not cut down their forests yet, etc.).”

    A international emissions tax would never work. First, nations have sovereignty that must be respected. Secondly, any nation that spends money on R&D would expect returns on investments. And Thirdly, accounting for past emissions is silly. Even if a nation did not directly emit CO2, it may have benefited from the emissions in another nation. In addition, nations that are taxed higher would be put at a disadvantage on world markets, and no nation would go along with such a proposition.

    Quite frankly, the best bet would be to get a pledge out of nations to spend so much money on R&D within their own nations. But I think a pledge is the most that can be hoped for.

  49. 199

    197 Kevin McK.

    Right you are on perpetual motion, though the scrubber is not an energy conversion machine.

    The point is that the energy to drive the process must be acknowledged, and it seems to often be the case, that it is quite a lot.

    You rightly refine my generalizations.

    I would need a serious explanation of how the CO2 could ‘offset’ carbon in the oil that I guess must be coming from coal? Of course you do not get any kind of hydrocarbon molecule out of carbon and CO2.

    I am perplexed by these kinds of things being accepted as being real possibilities. Not only do they all seem to involve energy consuming processes, they require much expensive equipment as well.

  50. 200

    197 Kevin McK.

    I apologize for misreading your last, where you said the CO2 would be used to extract oil from the ground.

    The CO2 would not offset carbon in the oil, it would offset the oil; just like water offsets oil in standard oil recovery operations. Sounds ok? Well, in water flood oil recovery operations a huge amount of water comes up with the oil.

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