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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. 201
    Brent Hoare says:

    Ray – Appreciate that your time to respond is limited, but as the Cancun talks draw to a close, small island states are calling for action on HFCs in order to “buy time” – see http://solveclimatenews.com/news/20101209/island-nations-plead-their-lives-world-dawdles-climate-talks?page=2 – through phasing out HFCs under the Montreal Protocol.

    Are they wrong to do so? Wouldn’t getting rid of the most powerful radiative forcers make a significant contribution to the task at hand, and even if this doesn’t provide an excuse for delaying action on the main game of CO2, surely dealing with this lowest of the low hanging fruit would be a useful contribution to stop us from digging an even deeper hole we will need to climb out of to avoid runaway climate change? Is this a better metaphor for advocates to be using than the notion of buying time? Or could you suggest a more accurate one?

  2. 202
    John Mashey says:

    re: #192
    Cement: that’s Calera.
    Without offering an opinion on whether this actually works, and at scale, the founder (a coral chemistry/ cement expert) lives in my town. His talk at Stanford started with a passionate 10 minutes of concern about corals, and then shifted into how they might use similar chemistry to sequester CO2 into cement/aggregate that lasts a long time, is a product that people pay for, and that avoids the CO2 production of regular cement. It can also consume stuff like fly ash, a multiple win if workable.

    He was very clear in saying that the only hope for corals was to do something about coal powerplants in particular.

    Although one always wants to keep an eye on Vinod, Calera has come a long way from when I first heard about it. By experience I am always skeptical of startup claims, at least on paper, the management team and advisors look very good, partners like Bechtel are serious. Of course, there have been many startups that looked good on paper, and I do not understand the electrochemistry and some serious folks have expressed doubts.

    But, I sure wish this one works, because (other than re-using CO2 to do oil-well injection), it’s one of the few that is not just a required burden, but consumes waste materials to make useful products.

  3. 203
    Patrick 027 says:

    Re 198 E.L.

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

    Yes, and why will they do that? You have indicated funding for R&D. But a price signal can also encourage innovation, and also, if, for example, coal electricity has a public cost of, for example, 4 cents/kWhe, then why should, for example, solar power, have to come down to coal electricity’s price to compete, when it would have net net economic benifit within 4 cents/kWh of the price of coal electricity? That’s where it would be handy to have a price signal, so the benificiaries of an emitting pathway pay the costs of the emissions. (Even when the costs of renewable energy, and/or (properly accounted) nuclear, and/or sequestration, etc, become competitive without the price signal, it still makes sense to have the price signal so that the market share can be optimized – ie that use of alternatives becomes so large that scarcity overcomes mass market advantage and learning curves that the marginal utility declines to the point where the next additional switch from coal/etc to solar/etc. would have no net benifit or cost, including the (for example) 4 cents/kWhe public cost of coal, etc.) (PS even with the tax, it may still make sense for public investment in R&D, and D&D (and some other policies), for perhaps multiple reasons, but one of which being that the PPC may not be convex everywhere (mass market advantage, learning curves) and another being that the market may get stuck in a rut out of habit (and customs) and it takes some exposure to alternatives in order to get the ball rolling.)

    A international emissions tax would never work. First, nations have sovereignty that must be respected.

    No treaties, ever?

    Maybe a tax is the wrong word. Let’s say nations are objectively assigned responsibilities, which they can agree with because it’s objective (a bit of optimism on my part, I admit), and they contribute to a fund accordingly. And part of the incentive to participate could be that they will not recieve their share of the funds in so far as they contribute their share (this won’t work for nations which would still recieve less than they would contribute, but they might not know that they’ll recieve less in the future because they might not be able to predict their future accomplishments; anyway, other factors are a sense of honor and shame. Depending on how things go in the future, nations which do not contribute and emit significantly may become denied various U.N. posititions, isolated, boycotted, embargoed and sanctioned, and eventually … But it may not have to come to that, perhaps in part because the policies stimulate innovation and investment and deployment to the point that it becomes much easier to join the treaty and reap the benifits of clean energy/etc. Also, without any other international agreement, I would suggest a domestic emissions tax with tariffs/subsidies proportional to differences in policies among nations; this could be applied to groups of nations as well; while there may be some economic pain in those nations which have the tax and use more expensive alternatives they or nations with similar policies produce instead of those from nations with different policies, I have to ask, wouldn’t there also be some pain in those nations whose exports suffer and imports increase due to the tariffs/subsidies of other countries? In other words, nations would have incentive to shift their own policies towards each other’s; this includes those which initially do not tax emissions, so those nations which venture out can exert pull on others. Besides, they will profit from there innovation and be able to supply more affordable clean energ/etc. alternatives to other nations.

    Secondly, any nation that spends money on R&D would expect returns on investments.

    Well, the fund might go in part to rewarding those nations/parties which share their technological developments more generously (and investments in other nation’s clean energy infrastructure, etc, (analogous to CDM from Kyoto) and proactive adaptation investments (aquaducts? crop breeding? desalination plants?); also the fund should pay for those otherwise uncompensated climate change costs (again, proactive adaptation; also, damages incured, compensation to climate-change refugees and/or their host countries.

    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.

    Accounting for past emissions would not be silly; it could be quite helpful for leveling the playing field so that the *same* tax rate can fairly be applied to all nations’ ongoing emissions so that they are not unfairly disadvantaged (the issue of past emissions would be addressed with a one-time transfer of wealth (one time as in not repeated; the payments would be over a period of years or decades; they would be indepedent of the taxes for ongoing emissions), it would in total be equal to the same tax rate applied to the world’s emissions in prior years, but then increasingly discounted going farther back in time, and also, increasingly back in time, being assigned to nations according to present accumulated wealth, since the wealth has moved from where emissions occured (this is an approximate method and suggested improvements would be welcome – although this might not be the place to discuss it at length); since climate-change related costs don’t correlate perfectly with accumulated wealthy, this will to some extent be a transfer of wealth from rich nations to poor nations – but it should be noted that (not to knock charity at all) this is not charity, it is paying debts. With this transfer, it should be easier for rich and poor nations to agree to pay the same rate according to emissions.

    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.

    Maybe, but those nations ought to pay for R&D (and D&D, and other things) with an emissions tax; otherwise it comes from a general tax – better than nothing but what sense would it make to choose the later over the former? Anyway, aside from the important issue of national climate damages not correlating with emissions, I would accept this solution, at least initially – see above.

  4. 204
    Ray Ladbury says:

    Brent Hoare,
    The “most powerful radiative forcers” as you call them actually trap relatively little radiation compared to CO2–indeed one of the reasons they have greater “sensitivity” is that they are not saturated in the central portions of their absorption lines.

    CO2 is the most important knob we have to twiddle precisely because of the same reason it is difficult to tackle: we produce a whole helluva lot of it. Going after lesser GHGs is nibbling at the capilaries when we really should be going after the jugular of this beast.

  5. 205

    #200–NO problem!

    I think we’re more or less on the same page with understanding the proposal Kilimanjaro makes; I’m agnostic about how well it would work, or how desirable it is. I just don’t have enough information. I believe, though, that it would probably be similar to the project described here:

    http://www.carboncapturejournal.com/displaynews.php?NewsID=613

    (Actually, this is the most detail I’ve seen on this project, though I’ve got to believe there’s more out there somewhere.)

    2.8 million tonnes of CO2 annually isn’t too shabby, but it’s still a long way to gigatonnes of carbon from there.

  6. 206

    I have a suggestion for the skeptical politicians. Every developed country that refuses to implement effective climate-change polices should be required to enter into a future contract that requires their nations to pay for the effects of climate change on poorer nations. In other words, if they are that confident that there will be no human-induced climate change (or no serious consequences) then they should be prepared to make a commitment to repair some of the damage, if they are proved wrong in coming decades.

  7. 207

    EL 198: People will just have to innovate a solution that is economically viable to compete with CO2 based technologies.

    BPL: Read my lips: We control CO2 or human civilization as we know it ends mid-century.

  8. 208
    Martin Vermeer says:

    Brent Hoare #201: it is true that these HFCs tend to have short lifetimes, e.g., here, less than 15 years; so cutting down on them without at the same time addressing CO2 would indeed be similarly useless. If would only postpone the inevitable loss to the waves of these island states. So, in this sad sense it would indeed be “buying time”.

    However, these gasses differ from black carbon and methane in an administrative sense: unlike the latter, HFCs can be simply phased out within the Montreal framework. This is much simpler than a management regime needed for black carbon and methane, which would need to be of similar complexity as — and would thus compete for political attention with — that for CO2. So in that sense the proposal is risk free.

  9. 209
    David Painter says:

    re-186
    thanks for the links and information.

    Calcium carbonate is mined worldwide and releases CO2 in cement production, shellfish secrete calcium carbonate and capture CO2. A developed process for manufacturing a form of limestone would lock up CO2 as would a process for manufacturing Iron carbonate (Sidderite). Nature produces both of these on a massive scale without investment or technology.

    I am not suggesting shellfish farms as a solution to CO2 capture; but FeCO3 and CaCO3 both lock up carbon atoms at a ratio of 3:1.

    CO2 oceanic schemes and CO2 drilling are possibly prone to uncontrolled release and possible Phretic effects may occur endangering life.

    Many geological deposits contain both limestone and Sidderite together in vast quantities (billions of tons)from the Jurassic showing they both form together in CO2 laden environments.

    A natural mineral capture process could be a scalable, cheap and stable method of CO2 capture with sand as a by product? I am unaware of any literature where this has been given any thought.

    A process like this could be developed as an on site scrubbing system for CO2 production hot spots like cement, oil refineries, power stations etc in the same way that Subteranean air filtration gravel beds are used for slaughterhouses to clean putrid air.

    Pure calcium is hard to find on the scales required but Iron is not and neither is CO2, so the question I would like to pose is “Could iron and CO2 be combined to form Sidderite (FeCO3) cheaply and simply, and capture at source CO2 before it is emitted on a meaningful scale?”

    Can we learn what the Dinosaurs did before we become them?

  10. 210
    Didactylos says:

    BPL has reopened his “human civilization as we know it ends mid-century” argument.

    I have to apologise to BPL. I had not seen his post #273, since Gavin had said “enough” and I stopped reading the thread for a while.

    He did indeed attempt to defend his point, but I think his defence just lays out the weaknesses in his argument. Part of my complaint is that the result isn’t particularly new. As he says himself, Dai got a similar result – but to the best of my knowledge, Dai did not jump to the same conclusion. In fact, Dai specifically mentions water management and drought mitigation.

    Water management is a topic that has been discussed recently by Vörösmarty et al (2010), but BPL has so far ignored it. I think that is unwise, since the paper makes important points: water management has a huge effect on water resources. In many regions, it is the difference between enough water and not enough water. But many parts of the world are already under water stress, and thus vulnerable. In the future, more and better water management can mitigate some aspects of climate change – but at a cost.

    BPL, have you read Parry et al (2005)? They repeat many of the points I have been making, including that by 2060, cereal production in developed countries is likely to be up, and production in developing countries down. Under most models, there is little global change.

    Certainly, this will cause problems – very likely severe problems. But jumping to the conclusion of a “global collapse” is naïve in the extreme. Speculate if you will, but don’t pretend that you have provided the evidence to support such a contention, or that you are repeating established wisdom.

    More studies that attempt to evaluate the effects of drought and climate change under varying scenarios will be useful. Pretending it is simple is not useful.

  11. 211
    Eli Rabett says:

    Of course there is always Eli Rabett’s simple plan to save the world which has the virtues of messing over those don’t want to help and helping early adopters. Oh yes, not everyone needs to play for Eli’s plan to work

  12. 212
    Patrick 027 says:

    Re 206 Michael Paine – Very clever formulation! (How would we force those skeptics to uphold their end of the bargain?)

  13. 213
    Patrick 027 says:

    Re 209 David Painter –

    CO2 sequestration as carbonate minerals has been studied as an option for reducing net anthropogenic emissions. From what I remember of one study, CO2 injection into aquifers could result in some fraction of that CO2 reacting and forming minerals; other possibilities include mining minerals to bring to sites to react with CO2, injecting CO2 into mineral sites, and using minerals to capture CO2 from air such as by crushing rocks and leaving the mineral dust out to enhance chemical weathering – or (an idea I had, not sure how well it would work) distributing the dust into the upper ocean (perhaps letting it blow out to sea) to reduce acidification and have the oceans take up more CO2. A year or ? ago, another commenter at RealClimate supplied figures for the energy needed to crush rock, which appeared to be small relative to the energy supplied from fossil fuels per unit CO2. Some approaches specifically use (ult-ra)mafic rocks (dunite, peridotite, minerals such as olivine), but so far as I know, with perhaps generally more rock per unit CO2, more common rocks could be used (?) (oceanic crust, underneath sediments, is generally mafic (basalt, gabbro); continental crust is more felsic (granite, etc.); the mantle is ult-ramafic, but some ult-ramafic rocks can be found at or near the surface in some places). (Because the reactions are product favored under some conditions, I wonder if some useful energy might be obtained from them – low temperature heating, perhaps? Electrochemical cells? But perhaps it would be too little to devote the necessary equipment to it?)

    Suggested searches:
    “co2 sequestration by mineral carbonation”
    “CO2 in situ sequestration dunite”
    “CO2 air capture and mineralization via mineral dust” (I just tried that; there may be some better version of it to get better results)
    “CO2 mineralization in aquifers” (just tried that, came up with second link below)
    also just found:
    http://en.wikipedia.org/wiki/Carbon_sink
    and
    “Modeling Enhanced In Situ CO2 Mineralization in the Samail Ophiolite Aquifer” http://adsabs.harvard.edu/abs/2010AGUFMGC31B0868P

    For any particular mineral reactants and products, the reaction is product favored for sufficiently high CO2 partial pressure and (so far as I know – see figure 1 at “Initiation of clement surface conditions on the earliest Earth” http://www.pnas.org/content/98/7/3666.full )
    sufficiently low temperature (the chemical weathering feedback depends on other things – the kinetics of the reaction (climate), supplied surface area of mineral reactants (mechanical erosion, sea level), etc.) – hence, at sufficiently high temperatures, such as found at sufficient depth beneath the Earth’s surface, the reaction can be reversed, eventually returning CO2 as geologic emissions (geologic emissions and geologic sequestration are both generally quite slow (with exceptions at times in Earth’s history); last I read, about ~ 0.2 Gt C / year).

    You wouldn’t generally want or need to actually supply metallic elements to produce carbonate minerals for CO2 sequestration because of the necessary energy input.

  14. 214
    Patrick 027 says:

    … of course, if we’re going to dig up (ult-ra)mafic rocks for CO2 sequestration, perhaps we should get some H out of it too (see ‘serpentinization’, for example: http://www.pnas.org/content/101/35/12818.full) – probably wouldn’t be worth it to get H from the rocks like that were it not for dual usage for CO2 sequestration; not sure it would still be sufficient amount to justify paying attention to it even given dual usage option, but something to think about…

  15. 215

    Did 210,

    Sorry, you’re wrong. Cereal production will NOT be greater under global warming. Check the literature. Your other points are egregiously wrong as well.

  16. 216
    Dappledwater says:

    J. Bullis – As I am informed here, the CO2 can become excessive and reduce the rate of growth of such creatures…….. It seems to me we are a long way from the acid level needed to do this latter action.

    The Arctic Ocean is projected to reach aragonite undersaturation by 2020. That means parts of the Arctic Ocean, particularly the deep ocean, will be corrosive to marine organisms that make their shells from aragonite.

  17. 217
    ccpo says:

    Re: Jevons
    What drives Jeavons’ is 1. desire and 2. population. Someone above forgot about population when calculating what would happen with consumption and treated it as a closed, static loop.

    Uh-uh. Nope. Population, like it or not, eventually trumps all. To demonstrate: Energy use in the United States between 1980 and 2000 or 2005 or so increased in efficiency by 33% or so. Consumption of oil alone, let alone all fossil fuels, rose by about the same percentage.

    Do people not read Diamond, Tainter, et al., regarding complexity and diminishing returns?

    So, we have not only population putting pressure on increased efficiency, but also decreasing returns. Technology cannot solve this. Less energy is less energy if the loss exceeds gains in efficiency, which it always does eventually. This means you must get over this idea of keeping things as they are today on future energy availability unless or until a true breakthrough occurs – which it never does…

    The other issue is that energy is not the only declining resource. There are a slew of them, and I bet you can’t guess the most dangerous one after oil, so I’ll share: phosphorus. We’re looking at supplies to maybe the end of the century. What then? (There is an answer. I’ll check back later to see who comes up with it first.)

    We must, even though this is a climate blog, think, discuss and solutioneer systemically.

  18. 218

    Speaking of losing time, and for that matter of black carbon & CO2 emissions, here’s a new paper relating to wildfire and AGW:

    http://www.cbc.ca/technology/story/2010/12/10/climate-change-wildfires.html

  19. 219
    Daniel Bailey says:

    Re: ccpo

    “Soylent Green”

    The Yooper

  20. 220
    Didactylos says:

    BPL said: “Sorry, you’re wrong. Cereal production will NOT be greater under global warming. Check the literature. Your other points are egregiously wrong as well.”

    First, don’t misrepresent what I said. That’s just rude. Second, why are you waving around “check the literature” when I actually cited a 2005 study that finds that in the time frame under discussion, developed regions are likely to see increased yields. And why is it so hard to understand? Some regions will have more precipitation, more CO2 and warmer temperatures. Developed regions also have enough money to spread that water around where it can do most good. It’s trivially easy to see how this translates into higher yields, until high temperatures become the limiting factor.

    Why do you have to sling mud instead of addressing yourself to the actual discussion? Did you even pretend to look at any of the studies I cited?

    If you want to be taken seriously, then you have to get serious. Acting like a moron will only get you treated that way, and any larger issue you are trying to highlight will be ignored.

  21. 221
    Patrick 027 says:

    Re 217 ccpo – population growth – greater than otherwise would have occured – is one way that consumption can increase in response to a reduction in price; *in the simplification of rational agents*1, why would it *necessarily*2 increase to the point that the price is the same as it was when it only supported a smaller population increase? In other words, if a price of $200 leads to consumption 1000 (with efficiency 50 %, so consumption of raw stuff is 2000), then why would a decline in price (via increase in efficiency to 100 %, or to someone else’s voluntary reduction in consumption) lead to an increase in consumption (equilibrium, or equilibrium deviation from a trajectory (think decay of transients)) so great that the price goes back up to $200, when the consumption (before processing) at $200 was only 2000?

    Take out either 1 or 2 and I think that’s still a good question; maybe taking out both qualifying statements leaves more leeway to ‘anything goes’, but my point is, while there is good logic to Jevon’s paradox, it doesn’t necessarily lead to total consumption (for some voluntary reductions) or consumption of resources (with efficiency gains) simply resuming to an otherwise fixed trajectory – in order for this to be the case, the demand slope has to essentially flat (or infinite – depends on which axis is Q and which is P; I forget the convention) – that’s a special circumstance.

    Or in other words, how much smaller would (population * per capita consumption) growth have been if efficiency hadn’t increased?

  22. 222

    Did 220,

    Your arguments on this are entirely driven by your personal dislike of me. Your likes and dislikes are your business, but I don’t have to enable your rants. Sorry, I’m not discussing this with you any further.

    [Response: Enough. If the entirety of your comment is simply an attack on another commenter, please do not submit it. This goes for everyone. - gavin]

  23. 223

    Googling “cancun update” this morning–in the absence of any substantive report that I’ve heard during a rather busy (for me) weekend–I found this depressing item:

    http://reason.com/blog/2010/12/10/further-cancun-update-agrees-t

    Basically what I feared: nada, of any substance at least.

    Is there anything more detailed out there I’ve missed?

  24. 224
    Brent Hoare says:

    Ray Ladbury #204 and Martin Vermeer#208: Many thanks for your thoughtful responses. The reason I call the F-gases the most powerful radiative forcers, and why they are often referred to as “super greenhouse gases” is a description of their comparative effect on a molecule of F-gas by molecule of any other ghg basis – of course the volumes compared with others are much smaller, but due to the multipliers of their massive GWPs, their impact is far from trivial. As pointed out in Velders, G. et al., (2009), “The large contribution of projected HFC emissions to future climate forcing”, Proceedings of the National Academy of Sciences, 106, June 2009 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2700150/), although contributions of HFCs are currently a small proportion, they threaten to erode the very substantial climate benefit we accidentally achieved by phasing our ozone depleting CFCs, which have even larger GWPs than the HFCs (see also Velders et.al. “The importance of the Montreal Protocol in protecting climate”, Proc Natl Acad Sci U S A. 2007 Mar 20;104(12):4814-9). If developing countries follow the path taken in the developed countries in embracing gases like R134a, R410a, R407c and R404a etc, and continue to overlook the available genuinely climate friendly natural refrigerant solutions, the HFC contribution is likely to grow to at least 10-20% of global emissions.

    As Velders says in the 2007 abstract, “The climate protection already achieved by the Montreal Protocol alone is far larger than the reduction target of the first commitment period of the Kyoto Protocol. Additional climate benefits that are significant compared with the Kyoto Protocol reduction target could be achieved by actions under the Montreal Protocol, by managing the emissions of substitute fluorocarbon gases and/or implementing alternative gases with lower global warming potentials.” As managing or containing emissions of F-gases has been an abject failure everywhere except the Netherlands (and even this is arguable, according to my Dutch colleagues), this leaves an urgent and rapid transition to natural refrigerants as the best available option.

    As much as I like the metaphor of going for the jugular vs nibbling at the capillaries, I really don’t think it applies in this case, and I don’t think the HFC problem has received anywhere near the attention it deserves from the scientific community or my dear friends and colleagues in the Environmental NGO community (with a few notable exceptions).

    I would be the last person to argue that acting to recover, destroy and phase out F-gases in any way relieves the imperative to curtail CO2 emissions (and following this discussion will urge the few ENGOs who are active in this space to review the “buying time” rhetoric!), but the scale of the problem surely demands that we haul on all the available levers to wind back every one of the dials that contribute to the problem?

    Martin raises the very sound point that HFCs are distinguished also by the potential relative simplicity of the administrative arrangements that are available to get rid of them, if the existing disjuncture between the Kyoto and Montreal Protocols can be remedied. Initial hopes that a big step towards this might have been among the outcomes of Cancun look not to have been realised, which is very disappointing.

    Nevertheless we will soldier on to achieve this goal, for as long as it takes to persuade India, China and Brazil to get out of the way of agreement to amend the Montreal Protocol to address HFCs, and to correct the colossal mistake of having subsidised and encouraged their introduction in the 90′s when far superior solutions were available even then. I’ve attended most of these meetings for the last 3 years as a representative of the natural refrigerants industry (still largely conspicuous by their absence c.f. the fluorolobby who turn up in hordes in a desperate struggle to maintain their market share and marginalise the competition, but it’s a huge advantage having truth on our side), so it’s good to be reassured the goal we are striving for is risk free – but it has thus far proved elusive, in spite of some of the most sophisticated campaigning in the business.

    It would help no end to have more prominent and influential voices pointing out that HFCs/HCFCs (and banks/illegal trade of CFCs) are a big deal, that the solutions are well (if not widely) understood and comparatively easy to implement and achieve, and to thereby help grow the political will to make it so.

    Currently this is sorely lacking, but much better late than never…;-)

  25. 225
    Hank Roberts says:

    > Sorry, you’re wrong…. Check the literature.

    http://imgs.xkcd.com/comics/wikipedian_protester.png

    > Cancun

    http://californiareport.org/climatewatch will lead you to:

    http://blogs.kqed.org/climatewatch/2010/12/12/tangible-if-minor-progress-in-cancun/

    A little while after a big climate meeting I always look for a thoughtful summary from Tom Athanasiou at http://www.ecoequity.org/

  26. 226
    Hank Roberts says:

    Aside, let me recommend a serious look around the KQED climatewatch site for quite a few relevant articles. They’re doing a good job

  27. 227
    Daniel Bailey says:

    Re: Kevin

    Different blog, same conclusion.

    The Yooper

  28. 228
    Didactylos says:

    BPL said: “Your arguments on this are entirely driven by your personal dislike of me. Your likes and dislikes are your business, but I don’t have to enable your rants. Sorry, I’m not discussing this with you any further.”

    Enable? Rant?

    Sorry, you lost me there.

    I don’t dislike you. I dislike some of what you say, because you refuse to back it up with any evidence, yet you repeat it loudly to anyone who will listen (and anyone who won’t), denier or not. You misrepresent climate change, and do a lot of damage in the process. You use the same tactics deniers use to push your own agenda – on a scientific blog. I refuse to give you a free pass just because we agree on most things.

    Gavin, if BPL really isn’t interested in any rational discussion, will you be able to edit out any repetitions of his unsubstantiated claims? Specifically, any claims of certain “global collapse” in 40 years?

    [Response: Look, I do not have time to police every argument that breaks out. But having people repeat themselves over and again is tedious, so please stop. If you don't want to engage with someone, don't. - gavin]

  29. 229

    Hank, Daniel, thanks for the links.

    The content wasn’t what I hoped for, but sadly wasn’t too different from what I expected.

    Appreciate the help.

  30. 230
    David B. Benson says:

    Didactylos @228 — Equally off-topic, I suppose, but via the link below you” find Dr. Dai’s drought review paper. I opine that BPL is close to correct.

    http://climateprogress.org/2010/10/20/ncar-daidrought-under-global-warming-a-review/

  31. 231
    ccpo says:

    Patrick, who cares about prices? I wasn’t discussing prices, I was discussing consumption. If you don’t understand that continually increasing population must end up overtaking any gains in efficiency, I really don’t know what to say. This is 2 + 2 = 4 stuff.

    100 people eat 100 apples at 10 cents each.

    Efficiency leads to a drop in price to 5 cents. 100 people still eat 100 ’cause they just don’t want more apples.

    110 people now exist and eat 110 apples. Ooops.

    See? LOL…. No matter how you slice it, lower prices or more people will lead to greater consumption (of a wanted item), with both, it’s even worse.

    Obviously, if you have a resource that is renewable and unlimitedly scalable, none of this would matter. Sadly, such resources do not exist, thus, Jevon’s applies.

  32. 232
    Didactylos says:

    David B. Benson: Thank you.

    I have read it, you know. I do my best to look at all sides of an issue, I don’t just charge in bull-headed.

    As I said earlier, Dai specifically mentions that he doesn’t take water management into account.

    For example, people living in regions with advanced irrigation systems, such as those in developed countries, can mitigate the impacts of drought much better than farmers in Africa and other developing countries

    Most importantly, he doesn’t make any claims that can’t be backed up by his research. You won’t find the words “civilisation” or “collapse” anywhere in his review.

    I don’t contest that Dai probably has very similar results to BPL. And eventually, climate change is likely to cause such severe drought that there is nothing we can do about it and civilisations fall.

    My point is that we aren’t there yet, and BPL’s argument requires not one, but many leaps of logic: that drought is the only relevant factor to agriculture, that civilisation collapses as soon as agriculture is strained, that the entire globe is so interconnected that the collapse is simultaneous, and that humanity stands by and does absolutely nothing even when a crisis is clearly underway.

    Those are the logical leaps, as I see them – but in addition, there are the factors that BPL has just ignored: existing and future water management, regional differences, positive effects of climate change that offset some of the negative effects in the short term – and so on, and on…..

  33. 233
    Didactylos says:

    ccpo: I’m not disagreeing with you, but have you considered that in places like India, demand for meat is rising rapidly as a result of a growing, prosperous middle class. Economic success can lead to increased consumption, and if we look at the US or Europe, there seems to be no practical ceiling until we’re all balloon-shaped.

    Supply and demand is a complicated subject, and I’m fairly confident that economists don’t understand it much either (although they hopefully have a better grasp than you or I).

  34. 234
    Ray Ladbury says:

    Barton,
    While you and Didactylos have had your differences, I don’t see how it benefits you or your argument to take his criticisms of your argument personally. I guarantee you will receive similar and probably tougher questions from referees and other researchers. I wonder if maybe you could look at some basic questions of hydrology–e.g. where does the water come from in key agricultural regions–and elucidate in more detail how drought would affect these areas specifically. Such areas would include California and the American Great Plains, but also, perhaps the Punjab and some of the major rice growing areas in Asia. In particular, how much of the water requirements now come from rain and how much from nearby rivers and aquifers. Then look at how the likely increased drought might affect all of these contributors. Agriculture is no longer widely dispersed. The effects on a few key areas could be critical for the viability of the food supply.

  35. 235
    David Painter says:

    re 213 – Patrick 027
    Thank you, lots to digest.

    was looking for information on practical trials or experimentation/research into existing accessible deposits. Thanks.

  36. 236
    David B. Benson says:

    Didactylos @232 — “This is very alarming because if the drying is anything resembling Figure 11, a very large population will be severely affected in the coming decades over the whole United States, southern Europe, Southeast Asia, Brazil, Chile, Australia, and most of Africa.” from Dai’s
    http://onlinelibrary.wiley.com/doi/10.1002/wcc.81/full

    Now go read what heppened to earlier civilizations when their region dried up.

  37. 237
    Didactylos says:

    David B. Benson:

    I never said it wasn’t serious! But our modern civilisation doesn’t compare to any past civilisation, in size, wealth, or population. Drawing some vague parallel is all very well, but as an argument, it lacks substance at every level.

    And what’s the biggest difference? In this context, it has to be technology. Water management technology, agricultural technology, distribution technology.

    Now if you want to limit your discussion to subsistence farmers in Africa, then you have a real point. I expect to see major famine in the next 20 years. There may be wars, but it won’t be the people suffering from malnutrition doing the fighting. Malnutrition doesn’t leave people enough energy for that.

    But even within Africa, there will be variations. Some regions will only see mild drought, other regions will see increased rainfall.

    Are you ready to stop dismissing this complexity with a single throwaway sentence?

  38. 238
    Patrick 027 says:

    Re 231 ccpo – just to be clear, are saying that the 5 cent drop causes the entire population increase (in this example)? What happens when the land resource value comes into play, and drives up the price when people want more apples?

    I wasn’t saying that consumption can’t grow in response to a price reduction; I was saying it won’t necessarily grow so much that it eliminates the price reduction. And this is relative to other changes; consumption could be growing and driving the price higher, but must it always return to the same trajectory?

  39. 239

    Ray 234,

    I have never yet come across a peer reviewer who used the kind of personal rhetoric Did uses. The simple fact is that he doesn’t know what I have and haven’t considered. He hasn’t read my paper. I don’t think he’s read what I posted here very carefully. He wants Gavin et al. to censor my posts here–did you miss that? All very different from what I get from peer reviewers.

    If you think I neglected crucial factors, why don’t I send you a copy of the paper? Then you can tell me what I missed.

  40. 240
    Patrick 027 says:

    About water management – 1 holding ponds, cisterns, reservoirs, etc. 2. pumping, aqueducts. 3 desalination: I remember reading of a device that can produce 1 m3 of fresh water with 3 kWhe (if osmotic pressure ~ 27 atm (?) ~ 270 m of water head ~ 2.7 MPa, 2.7 MPa * 1 m2 * 1 m = 2.7 MN*m = 2.7 MJ, 2.7 MPa = 2.7 MJ/m3, so 3 kWhe doesn’t require efficiency > 100 %);

    3.6 MJ/kWh * 3 kWhe = 10.8 MJe

    10 cm/year (a precipitation shortfall for illustrative purposes)* 5 E12 m2 (~ 3.3 % global land area) = 5 E11 m3/year

    5 E11 m3/year * 10.8 MJe/m3 = 5.4 E18 Je/year ~= 171 GWe

    Just to consider.

  41. 241
    David B. Benson says:

    Didactylos @237 — I’ve lived here in a dryland farming region for 40 years now.

    No precipitation over the winter, no crop.

    Despite the state’s ag school being here.

    Look very carefully at what Figure 11 is showing you.

  42. 242
    Ray Ladbury says:

    Didactylos,
    You seem to be suggesting that somehow modernity and complexity confer immunity to collapse. I don’t think this is the case. Food security is really a very recent thing, and it has been achieved by intensive agriculture in a few regions of the globe. A hit to any of those regions could be catastrophic for food supply. The very fact that we ship grains and even perishable tropical fruits around the globe illustrates how interconnected–and so how potentially vulnerable–our civilization could be. There are a whole lot of challenges between us and where we need to be to make civilization sustainable. Failure to negotiate any of them could be catastrophic–and climate change may be among the most challenging.

  43. 243
    Hank Roberts says:

    Perhaps the contention could get a room?
    There’s a place: http://thirdreviewer.com/

  44. 244

    216 Dappledwater,

    You say, “The Arctic Ocean is projected to reach aragonite undersaturation by 2020. That means parts of the Arctic Ocean, particularly the deep ocean, will be corrosive to marine organisms that make their shells from aragonite.”

    I can understand that insufficient aragonite would slow the growth of marine organisms. Is the word ‘corrosive’ appropriate?

    Then I question what you mean by ‘deep ocean’. Are marine organisms capable of making shells still active in ‘deep ocean’ water?

    Then, what is the process by which aragonite is reduced to undersaturation?

    I would not like to leave anyone with the notion that I know what aragonite is, but since it seems to go away with higher CO2 concentrations that process must in itself take up CO2. Then, as the aragonite depleted water is drawn down into the thermohaline circulation, that would seem to carry CO2 also, into the deep. Right?

  45. 245
    flxible says:

    JimBullis@244 – Instead of speculating about something which you state you know nothing about, why not do at least a basic investigation and not further confuse yourself by acting like you know what “would seem” to be the processess involved?

  46. 246
    Dappledwater says:

    J Bullis @ 244 – “Is the word ‘corrosive’ appropriate?

    Yes. Imminent ocean acidification in the Arctic projected with the NCAR global coupled carbon cycle-climate model

    “Aragonite undersaturation in Arctic surface waters is projected to occur locally within a decade and to become
    more widespread as atmospheric CO2 continues to grow. The results imply that surface waters in the Arctic Ocean will become corrosive to aragonite, with potentially large implications for the marine ecosystem, if anthropogenic carbon emissions are not reduced and atmospheric CO2 not kept below 450 ppm.

    In conclusion, human activities are perturbing the ocean and the habitats for marine organisms. The results of this study and of Feely et al. (2008) for the coastal North Pacific and Orr et al. (2008) for the Arctic show that undersaturation of surface waters with respect to aragonite is likely to become reality in a few years only.”

    Are marine organisms capable of making shells still active in ‘deep ocean’ water?

    An error on my part, I meant deeper water, not the “deep ocean”. Calcium carbonate becomes more soluble at higher pressures and lower temperature.

    Then, what is the process by which aragonite is reduced to undersaturation?

    The consequences of the excess carbon dioxide dissolved into the oceans are not only an increase in hydrogen ions (lower pH), but a reduction in the concentration of carbonate ions. It just so happens that these carbonate ions are building blocks for the calcium carbonate shells of many marine creatures, and the carbonate stable when the concentration of carbonate ions in seawater are supersaturated. Once the concentration becomes undersaturated the chemical reaction which formed the shells swings the other way and the calcium carbonate shells dissolve. Aragonite, being a more soluble form of calcium carbonate than calcite, will be affected first by the ongoing change in seawater chemistry.

    I would not like to leave anyone with the notion that I know what aragonite is, but since it seems to go away ……

    The alternative to guesswork might be to read the peer-reviewed literature on the topic.

  47. 247
    Didactylos says:

    Ray Ladbury:

    If that’s what you are taking away, then I’m evidently still not being clear enough. I’m not making any absolute statements. I’m just saying that making such specific claims cannot be justified based on the wide variety of evidence and uncertainty.

    Note that this isn’t the same as denying climate change because of uncertainty. We know climate change will make our world almost completely unliveable eventually, whether climate sensitivity is 2.5 or 3.5 degrees per doubling. Something like “civilisation”, though, is hard enough even to define, let alone make sweeping statements about.

    Maybe there is sufficient evidence that certain parts of the world are likely to “collapse” by 2050. Maybe there is sufficient evidence that the majority of the world will have collapsed by 2100. Nobody has yet even attempted to provide any evidence along these lines, or even consider just what sort of evidence would be required to meet varying degrees of certainty. Analysis of water management would be just the very first step.

    As you mention, analysis of what regions are exporters of food and which are importers, and how climate will affect those regions is vital. You would also have to consider that some regions are able to grow crops, but currently it isn’t economically viable. A changing world is likely to alter such underlying assumptions.

    [edit - enough!]

  48. 248
    Didactylos says:

    BPL:

    You are complaining that I haven’t read your paper (I haven’t had the opportunity). But I’m not arguing against your paper, I am discussing the things you have said repeatedly in the blogs where you comment. I’m not a peer reviewer, and a blog comment isn’t a peer reviewed journal article. But that doesn’t mean we can’t take the time to try to get the facts straight, and not say misleading or false things.

    As I have said before, I do not believe your journal article will repeat the things you have been claiming in the blogosphere. If you had, it should have failed peer review. No, I’m sure that you will employ the language of uncertainty, and say “may” and “probably” and “perhaps”. You won’t say anything is certain.

    And this is exactly the behaviour we abhor in deniers: they get a perfectly adequate, unexciting paper published, then they spin it and say things about it that simply aren’t justified.

    I thought you had higher standards. Perhaps you can still claw back some respect?

  49. 249
    Didactylos says:

    David B. Benson:

    You are extrapolating your personal experience to the entire globe?

    Your arguments are just handwaving. Many of the issues I am raising have already been studied (in isolation). There is a huge amount you could say based on substance, but you have chosen anecdote.

    If you aren’t interested in the subject, that’s fine. I’m not forcing you to debate, and it’s not you making the unsupportable claims. Climate change is going to be quite bad enough based on the real evidence we have.

    Trying to save the ship from sinking is really a lot more useful than working out exactly how and when the ship will sink. But saying you already know the exact hour the ship will sink? BPL is almost literally predicting the end of the world.

  50. 250
    David Painter says:

    Re “Reducing soot and the other short-lived pollutants would not stop global warming, but it would buy time”..

    Reviewing the Infra-red cloud images of western Siberia over the last few weeks, it is apparent that the Infra-red signatures for the Vankor and Urengoy oil and gas fields are visible THROUGH fairly thick cloud layers indicating immense energy dissipation.

    I have never seen this at other locations even at South Pars/North Dome (Iran/Qatar-worlds largest gas field) or the U.S. It appears to even exceed Nigeria in detectable output on METOP Ch3/Ch4/Ch5 images.

    This indicates that during the exploitation of Gas and oil fields; the already banned practice of burning off gas unwanted products continues and is getting worse.

    Surely there can be no reasonable argument against the immediate ceasation of the practice; especially as a major part of the production is in or near the Arctic circle.

    As Russian production is estimated by the world bank to account for approx 50% (including new online fields)of global emissions, this should be an obvious detectable, measurable, and verifyable target to test the global resolve to save our own future and prove the point above?

    My own observations over the last few years show decreasing winter cloudcover over Siberia, not surprising considering as effectively they have the heating on all winter. From cloud patterns, emissions also head north and go out over the northern polar sea.

    Barrel of oil=42 Gallons
    weight of propane 4.11lbs/gallon
    4*42=168lbs propane= approx 76Kg
    76kg*46mJ/Kg=approx 3496mJ per barrel

    1.0 US gallon = 3.79 liter
    Propane:- the energy density of propane is 46.44 megajoules per kilogram.
    (propane is a waste product as can’t be transported)

    If approx at a low estimate, 10 barrel of oil per hour burnt per flare, 3496mJ*10*(roughly >2000 flares)=
    approx 70,000,000 megajoules per hour of heat into the siberian winter atmosphere. The air displacement effect on nominal cloud patterns and air volumes; soot and other effects surely has more merrit for attention than other longer term alternatives that will still have to clear this climate input up at a much later date?

    There are more fields that are shortly to be developed using the same outlawed practices.
    http://en.rian.ru/russia/20100127/157696641.html


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