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Drying out

October 9th, 2006

There’s been a lengthy debate in the comments threads of recent posts about whether the dry weather in much of Australia in recent years can be attributed to climate change, or is just another round in the natural cycle. One point that’s emerged is the crucial role of evaporation in exacerbating drought conditions. This was first observed in relation to the 2002 drought. The steady increase in global temperatures, including average temperatures in Australia, means that even when rainfall is at or near the historical average, conditions are drier than before because evaporation rates are higher. When we get a drought, as at present, conditions that would once have been bad are now extreme.

The combined effects of low rainfall and high evaporation are amplified when it comes to runoff, since the amount (net of evaporation) absorbed by the soil does not change much. And land use changes such as the construction of farm dams have reduced the amount of runoff that makes it into streams (these are now being restricted, but it’s often a case of too little too late). It’s not surprising then, as reported by Mark Neal at the RSMG blog, that, in terms of inflows to the River Murray system, 2006 looks set to be the driest year ever recorded.

So far, the effects on flows and allocations of irrigation water have been offset to some extent by accumulated storage, but with a run of dry years, that can’t be sustained. At the end of September 2006, total River Murray
system storage was 3 550 GL or 37 per cent of capacity, which is only half the long-term average for September of 7 000 GL. With winter and early spring being extremely dry, the chance of significant improvement this year is low, given that 60% of inflow typically occurs during July to October.

But if the situation is bad now, imagine the possibilities if the Cap on extractions hadn’t been imposed back in 1994. We would have started with lower storage levels, and there would have been that much less to draw on.

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  1. econwit
    October 9th, 2006 at 22:28 | #1

    “the River Murray system, 2006 looks set to be the driest year ever.”

    You are doing it again, try driest year ever recorded.

  2. Tam O’Shanter
    October 9th, 2006 at 23:22 | #2

    and once again starting a new thread when you have no answers to issues raised in the last on the same topic, eg Ian Castles’ despite your promises to respond in detail.

  3. jquiggin
    October 10th, 2006 at 05:44 | #3

    Econwit, thanks for this correction

    TOS, lengthy responses go in new posts, not in comments threads where no one reads them. This post shows that my original claim that the weather now is very hot and dry compared to the historical record is correct. As econwit notes, on the most relevant measure it’s the driest ever recorded.

  4. frankis
    October 10th, 2006 at 11:00 | #4

    Hey! – I read them (but carry on, Ian Castle’s debating abilities are impressive).

  5. Ian Castles
    October 10th, 2006 at 12:24 | #5

    Thanks Frankis – my main interest is improving the standard of discussion on these important issues.

    Roger Jones, I note that you posted on “The Browning of Australia� thread at 8.49 am today. Now that I know that you’re still following this blog, would you be able to answer some questions that interest me?

    (1) You said that the ABARE AP6 reference scenario gave an upper temperature rise to 2030 which was almost as high as the highest IPCC scenario, and that the ABARE scenario was “largely based on IEA projections.� But the IEA Reference scenario CO2 emissions to 2030 are the same as the LOWEST IPCC projection (B1). What is your source for the statement that the ABARE projections are largely based on the IEA’s?

    (2) I quoted the IEA’s statement that financing the required investments in energy-sector investment in non-OECD countries in the next quarter-century “is one of the biggest sources of uncertainty surrounding our energy supply projections.� I pointed out that the IPCC scenarios project increases in global use of electricity two to three times as great as the IPCC scenarios. That presumably means that two to three times the volume of net investment in power supply and distribution would be required, compared with what the IEA regards as one of the biggest source of uncertainty in its energy supply (and therefore emissions) projections, in order for the relevant emissions being used in CSIRO’s analyses to be realised. I asked whether CSIRO fed this sort of information into its uncertainty analysis. This seems to be a simple “Yes/No� type question: what is the answer?

    (3) You said that “The methods we have developed and are using draw on the breadth of emission pathways from low to high�, but so far as I know you haven’t modelled the low emissions pathway of the scenario that the Australian Government proposed that the IPCC should develop in its submissions on the scoping of AR4 in 2003 (i.e., lower population than A2, lower economic growth rates than B1). Surely this has to be done before the CSIRO can claim that its methods are drawing on the breadth of emissions pathways?

    (4) On the other hand, and despite the IPCC pronouncing that the SRES set of scenarios were sound and suitable for use in AR4, “CSIRO commissioned ABARE to analyse a range of illustrative greenhouse gas emission reduction scenarios [and]… The scenarios analysed include a reference caseâ€? (Ahammad et al, July 2006, “Economic Impact of Climate Change Policyâ€?, ABARE Research Report 06.7: p. 6). This reference scenario projects higher emissions in 2100 than any of the six IPCC illustrative scenarios. You have run it through MAGICC to get projections of temperature increase and these are quoted in Matysek et al (2006), yet you say that the full assumptions underlying the projections aren’t yet publicly available because of contractual obligations. My question is “Given the Government’s stated policy of support for the IPCC and the availability of the large set of SRES scenarios in which projections of driving forces and the emissions profiles of all relevant species of GHGs and sulphur are published in a 600-page report, why was a new scenario developed for use in the AP-6 exercise?â€?

    (5) You have said that “If high emission rates are plausible, then we should be factoring the impacts due to these into risk assessments�, but the basis on which you are deciding that high emission rates are plausible is not clear. For example, has any economist or financial market expert expressed the view that it is plausible that the growth in global power capacity could be two or three times as great as that projected by the IEA, which gathers masses of information about plans and forecasts from governments, power supply authorities, etc from around the world? If all “real world� experts believe this to be impossible, it doesn’t seem sensible to say that it is “plausible� on no better grounds than that they fit “storylines� developed by the SRES writing team.

    (6) Finally, yesterday’s and today’s “Canberra Times� carry stories of a report that was commissioned from CSIRO by the International and Climate Change and Development Roundtable. This report does not appear to be in the public domain, yet today’s CT reports that “a reference in yesterday’s CT to 150,000 million peoople potentially being displaced by rising sea levels by 2050 should have read 150 million people. This was an error IN INFORMATION SUPPLIED BY THE CSIRO� (EMPHASIS added). In my view, it is improper for CSIRO to provide information to the media but not make this information available for public scrutiny. This morning’s story says that the CSIRO report was “compiled with the support of aid agencies�, and yesterday’s report quoted the Roundtable as saying that “more than 70 per cent of people did not have access to electricity.� The correct figure is about 25 per cent, but the more important point is whether the CSIRO have informed the Roundtable of the assumptions underlying the climate projections. Does the report say, for example, that some of the IPCC projections assume that the whole of the developing world will be using several times the amount of electricity per head as is used in the richest countries in the world today? Do you think that this is likely to happen?

  6. Roger Jones
    October 10th, 2006 at 14:36 | #6


    I’m not sure that this is quite the place for a tête-à-tête. Nor did I, sending a note this morning, intend to write an opus this afternoon. Some quick responses but I don’t intend to pursue this line further in this thread.

    1. Based on means that various sources of data, including the IEA’s were the starting point but the reference scenario is the product of ABARE’s GTEM model. On P17 of their report, ABARE state “The updated database for combustion carbon dioxide emissions in GTEM was constructed in two stages, based on energy and emissions data reported by the International Energy Agency (IEA 2004c, 2005a,b). First, IEA estimates of emissions from fossil fuel combustion were mapped to the GTEM database according to the concordance between the IEA energy data and the GTEM energy data described in Hester and Ahammad (2002).” If I gave any impression otherwise it was unintended. Further reading of that report will give comprehensive detail as to the methods used and equiries as to the work should be taken up with ABARE – the experts in the matter.

    2. No. I don’t see how investment directly affects climate impacts through climate change other than in the underlying emissons. Our main sources of uncertainty are the emission scenarios themselves (produced by others), climate sensitivity, some radiative forcing terms and the difference in regional climate projections between models.

    3. I was referring to risk analyses carried out in impact assessment, which include the use of SRES projections from B1 through to A1F. CSIRO’s climate modelling is carried out by another team – the impact scientists draw from CSIRO’s climate modelling but we also draw from the modelling of a range of groups around the world.

    4. The Ahammad et al. (2006) report was carried out for the Energy Futures Forum. This work has not been completed and will be released in the coming months. Warming projections were not those quoted in Matysek et al. (2006) – the Matysek report discussed the AP6 reference scenario. I calculated those warming as a favour at the time – new projections attached to EFF work will be released with the EFF results.

    Re the government’s support for the SRES scenarios. At some stage, new scenarios have to be developed. The lead time for the development of new scenarios, their use in climate models, the subsequent analysis in impact assessments takes a number of years (~5; though we hope new tools we are building can speed up this process). For example, it has taken this long (since 2000) for the SRES scenarios to be widely modelled in GCMs, used in impact studies and reported. There is no reasonable substitute at this time. I for one, welcome new scenarios but we also need a robust process that assesses these as they are developed. I recommend a watch on the IPCC website to determine the emerging process for subsequent assessments. The 2005 scoping paper for new scenarios is here
    http://www.ipcc.ch/meet/othercorres/ES2WSscopingpaper.pdf but the meeting report from early 2006 has not yet been posted.

    5. Yes, they have, but it’s work in progress.

    6. The CSIRO report was supplied to the Roundtable who are taking responsibility for its distribution.

    I do not know enough to answer your final question. I am satisified with the general state of the SRES scenarios, but not all the detail (see Van Vuuren and O’Neill, Climatic Change, 2006; http://www.springerlink.com/content/d1357287j8646425/). Improvements can always be made but I am conscious of the long lead time required. I think I can say that the modelling community, or at least those involved in discussions surrounding the next generation of scenarios, would welcome new and better products.

    Even under the B1 scenario, the world faces substantial risks (e.g. to coral reefs, regions with low adaptive capacity, low-lying areas, small islands etc). We call them as we see them, and people can make up their own minds. There may be claims that people are being misled because of the underlying state of the scenarios, but to many scientists who have investigated to consequences of even low to modest levels of warming, the world is capable of producing a level of climate change that is worth avoiding if possible. Let’s have a discussion about how that may be done.

  7. tam o’shanter
    October 10th, 2006 at 18:51 | #7

    jquiggin said (at Browning of Australia) October 10th, 2006 at 5:09 pm

    … I have no reason to doubt that global warming is INCREASING mean global rainfall, and I’ve certainly never said anything different (sic!)….
    Coming back to the main point, if you want to continue the dispute over the conclusion that the weather is, as I said at the start of all this, getting hotter and DRIER (sic) [as we have discovered in the discussion, as a result of higher evaporation as well as lower rainfall], I suggest you move the discussion to the thread on “Drying out�. [my caps]

    So which is it, increasing rainfall or increasing dry?

    In fact global warming models are united in seeing increased evaporation as enhancing the greenhouse effect but their modelling of precipitation is often nil or very limited, when in fact it is part of the automatic stabilisation and cooling mechanisms in the climate system. (e.g Kasting 2006, p.353, in Frontiers of Climate Modeliing, eds. Kiehl and V Ramanathan, CUP, 2006.)

  8. Ian Castles
    October 10th, 2006 at 18:56 | #8

    Thanks Roger. My responses follow.

    1. I’m not sure that I understand your statement that ABARE’s reference scenario is the product of its model. A scenario is a description of the future based on assumptions, and ABARE’s reference scenario could presumably be modelled by each of the six IPCC modelling groups. What I’m querying is why a new set of assumptions needed to be developed at all.

    You said on the earlier thread “Interestingly, the recent ABARE AP6 reference emission scenario gives an upper temperature almost as high in 2030 (0.05°C lower and it is largely based on IEA PROJECTIONS” (EMPHASIS added). Now that you’ve explained that you should have said that ABARE used the IEA database of energy and emissions HISTORICAL DATA, I don’t see what’s interesting about this. A projection of future global population isn’t made more credible if it’s based on the UN Population Division database of historical demographic statistics.

    You say that ABARE are “the” experts on the matter of emissions projections That may be CSIRO’s opinion, but the Australian Joint Academies’ 1995 study “Climate Change Science: Current Understanding and Uncertainties” took a different view. That study found that “Australia is fortunate in having developed a range of economic modelling approaches that enjoy high respect in the international discipline of climate change economics”, and named the general equilibrium models under development at the Australian National University and Monash University associated with Professors Warwick McKibbin and Peter Dixon respectively. These economists and their associates are held in the highest regard internationally, and both groups are well represented in the peer reviewed literature.

    2. I did not suggest that investment could affect climate other than through the underlying emissions. But emissions will obviously be lower if most of the power generating capacity that the IPCC modellers assumed would be built between now and 2030 isn’t built. I infer from your answer that CSIRO does not attempt to evaluate the probability or otherwise of scenarios produced by others. I don’t think that that prevents CSIRO from informing its clients about the assumptions that were made in the scenarios that it has used in its own work, so that they can make their own judgments about their likelihood.

    I’ve previously noted the erroneous statement in a December 2005 research paper by eight members of CSIRO’s climate impacts team, including yourself, that “The SRES emissions scenarios currently available were deliberately constructed to be equally plausible.” It’s now seven months since I drew attention to this matter, and I’m surprised the error has still not been corrected.

    3. The projections from B1 to A1FI don’t cover the full range of the SRES emissions projections. The SRES authors have themselves explained that “The fact that 17 out of the 40 SRES scenarios explore alternative technological development pathways under a high growth … scenario family A1 does not constitute a statement that such scenarios should be considered as more likely than others with a less dynamic and technological and economic development outlook, nor that a similar large number of technologicxal ‘bifurcation’ scenarios would not be possible in any of the other scenario families.” So if the full breadth of emissions pathways is to be covered, the case for including a B1T scenario is just as strong as the case for including A1FI.

    4. Thanks for the clarification. I thought that a report on the Expert Meeting in Seville that you attended earlier this year on new emissions scenarios was available on the IPCC website. Last year I wrote several times to the World Bank’s Chief Scientist, Dr. Bob Watson, asking the Bank to provide the economic data in the scenarios produced by the IPCC (MER), UNEP (MER). IEA (PPP), US EIA (PPP) the Millennium Ecosystem Assessment (MER) and the Bank itself (PPP) on an internationally comparable basis.

    My suggestion was that this could be done under the guidance of the Technical Advisory Group to the International Comparisons Project, and several members of this Group wrote to me to register the hope that I would get a positive response. But I received no response, and I can only assume that there are interests that want to maintain their own “set of books” and fear that they will prejudice that position if the output assumptions underlying the various scenarios can be readily compared.

    I don’t see how a “robust process” for enabling new scenarios to be assessed can be developed unless and until the IPCC engages with the mainstream economics and statistics community.

    5. I’m glad to hear it, and I await the outcome with interest.

    6. I’ve read the Van Vuuren and O’Neill paper that you cite, and also the editorial comment that precedes it by Dr. Alison Stegman of Australia’s Macquarie University. I agree with Dr. Stegman’s assessment. I can assure you that your satisfaction with the general state of the SRES scenarios is not widely shared among economists and economic statisticians.

    In my view these scenarios in their present form are unusable for policy purposes, and this is equally true of the ABARE reference scenario. I also think that the use by the IPCC and ABARE of invalid concepts of output, energy intensity and emissions intensity is in breach of UN ECOSOC resolution 1993/5 of 12 July 1993, and is leading to serious waste and confusion not only in the IPCC/UNFCCC contexts but in other areas of policy. I don’t see how the discussions of mitigation and adaptation options is helped by this state of affairs.

  9. chrisl
    October 10th, 2006 at 19:11 | #9

    Ian Castles,
    As always precise, well argued, well informed.

  10. jquiggin
    October 10th, 2006 at 21:40 | #10

    “In my view these scenarios in their present form are unusable for policy purposes, and this is equally true of the ABARE reference scenario.”

    Could you explicate this a bit further. Are you saying
    (1) Some other (currently available) scenario should be used ?
    (2) We should make policy decisions on some (currently feasible) basis not involving scenarios ?
    (3) We can avoid making policy decisions until satisfactory scenarios are available?

    Like you, I can see plenty of problems with the SRES and ABARE scenarios. I tend to lean to position (2) and to argue that since we can tell from first principles
    (a) that business as usual will lead to growing emissions; and
    (b) that growing emissions will lead to disastrous environmental consequences
    we should not worry too much about the scenarios and get on with setting up institutions to reduce emissions.

    Is this your view also?

  11. Ian Castles
    October 10th, 2006 at 23:06 | #11

    John, I think the IEA Reference scenario offers the best starting point, but that the priority should be to develop it more fully to cover GHG emissions other than CO2 and aerosols rather than devoting too much effort to modelling emissions in the latter half of the century. Like the SRES authors, I don’t find the “business-as-usual” description a helpful approach: it seems to me to be better to distinguish between scenarios that exclude explicit climate related policies (such as the SRES scenarios) and those that identify specific climate-related policies such as those developed by the Energy Futures Forum and modelled by ABARE.

    If the distinction is drawn this way, then emissions projections excluding explicit climate policies certainly mean that emissions will increase in the short-to-medium term (up to around 2030). But If one is to believe the SRES and particularly the analysis of technological possibilities in the SRES (of the kind illustrated in Box 4-9 of the Report) it’s not obvious that institutions whose explicit purpose is to reduce emissions will be required, although they may be.

    I don’t agree that it’s sensible to set up targets for emissions reductions of a specific size by a given date, such as (for example) South Australia and the CSIRO Energy Transformed Flagship program have done. With apologies for its length, I’ll paste in a comment made by Peter Hartley on the Climate Audit thread yesterday. I don’t agree with all of Hartley’s points, but I believe that he is right on the fundamental point that the policy response to climate change requires input from many disciplines.

    “The following statement: ‘The complexity in the greenhouse warming issue is that if we wait until we are convinced as to whether the models have predictive value, then we may have missed a window of opportunity for action if the predictions of the models are actually correct’ may contain some implicit policy analysis that goes beyond the science. Whether or not we have missed a window of opportunity for action depends on the optimal action assuming the predictions of the models are actually correct. While it might seem obvious to many scientists that the optimal action is to eliminate, or at least severely curtail, growth in CO2 emissions under those circumstances this may not be the case.

    First, continued growth in CO2 emissions may have other benefits. For example, faster economic growth is itself of value for many reasons, including allowing us to afford more R&D on new energy technologies. Bringing fossil fuel technologies to more developing countries in particular also has many benefits for health and welfare more generally. Economic growth is also the best known method of reducing fertility rates, and there is very good evidence that CO2 emissions are more strongly related to population growth than to economics growth. The key reason is that economic growth tends to be associated with reduced CO2 output per unit of GDP. Thus, allowing higher growth rates of CO2 emissions in the short run may, by allowing faster rates of economic growth, actually lead to a sharper long decline in CO2 emissions in the future.

    The aerial fertilizer effect of added CO2 in the atmosphere is a second reason that eliminating or severely curtailing growth in CO2 emissions may not be an optimal policy even if the GCMs are accurate. The increased productivity of agriculture from the aerial fertilizer effect may be quite important in enabling the earth to feed the likely population in the next 40 years (until lower fertility rates spread to more countries). These benefits of CO2 need to be offset against the possible climate-related costs.

    Third, if there is a substantial chance of natural climate change, an optimal response to anthropogenic climate change might be to focus on adaptation and mitigation of losses rather than reducing the growth in CO2 emissions. Adaptation and mitigation strategies could protect against climate change regardless of its source. This could give us much greater returns on our investment in protecting ourselves from climate shocks.

    Fourth, it is likely that continued technological change will make it much less costly to reduce CO2 emissions in the future, or to extract and sequester CO2 should that prove necessary. Making expensive reductions today may not make much sense if we have good reason to expect that the same reductions could be made in, perhaps only 20 years, at far lower cost.

    Fifth, the supposition that “the models are actually correct� is in fact a bit of a “leap of faith� at the moment. Given the funds now being spent on climate research and the much better climate data collection tools we now have in place, it is likely that we will learn a great deal about climate in the next decade or so. The large uncertainty that still exists regarding the mechanisms that control climate means that any investment aimed at affecting future climate is very risky. Accordingly, the expected return needed to justify such investments therefore has to be much greater.

    Other considerations are no doubt relevant. My point here was really to observe that indeed the climate issue involves many disciplines. In particular, there is also expertise outside of the scientific areas (and statistics) that is relevant once you start talking about policy. Too much of the debate about policy in this area has been conducted by people who have not in fact thought very carefully about what optimal policies might look like. It seems to be assumed that the “obvious� response of reducing emission growth follows logically solely from identifying the problem.�

  12. proust
    October 11th, 2006 at 02:56 | #12

    Too much of the debate about policy in this area has been conducted by people who have not in fact thought very carefully about what optimal policies might look like. It seems to be assumed that the “obvious� response of reducing emission growth follows logically solely from identifying the problem.

    Amen. Amen to the entire Hartley comment quoted above by Ian.

    What Hartley fails to mention is that those who choose the obvious response tend to have a political motivation for doing so. Either you are an anti-development greenie who would dearly like to see the footprint of humanity reduced, or you are a socialist who longs for the bygone days of big government action (and who would love to see the evil capitalist polluters punished), or you are a scientist who enjoys the prestige and funding associated with your discipline suddenly becoming critical to the future of the human race.

    Ok, a bit of a troll I’ll admit. But not far from the truth from where I sit.

  13. jquiggin
    October 11th, 2006 at 06:37 | #13

    I agree with Ian and Hartley that the response requires input from many disciplines. But I’m unimpressed by the rest of Hartley’s argument. In particular,

    “economic growth tends to be associated with reduced CO2 output per unit of GDP. Thus, allowing higher growth rates of CO2 emissions in the short run may, by allowing faster rates of economic growth, actually lead to a sharper long decline in CO2 emissions in the future.”

    is just wrong. I’m surprised that a competent economist would write something like this. The long-run effect of an increase in the cost of CO2 emissions will be larger than the short-run effect, not smaller. And although it’s not strictly relevant, the implicit claim that reducing CO2 emissions will reduce economic growth sufficiently for any kind of second-round effects to matter is also false. We’re talking about a gross output loss of perhaps 3 per cent by 2050, an effect too small to notice even against the background noise of the medium-term macro cycle.

    Finally, co-operation between disciplines is a two-way street. Pushing dubious scientific claims like CO2 fertilisation, on which Hartley has no particular expertise, is not the way to go. It’s only one step further to the nonsense of someone like McKitrick, an economist who claims to have shown that there is no such thing as a global average temperature.

  14. Roger Jones
    October 11th, 2006 at 08:03 | #14


    some quick responses.

    1. Your restatement of the Academy’s view that Australia has a great deal of economic modelling expertise is acknowledged. However, economic modelling expertise does not mean that one has the tools for producing detailed scenarios. Van Vuuren and O’Neill make the point that there is no group producing scenarios of sufficient detail at present. In particular, being able to produce CO2 and even CH4 and N20 emissions is not sufficient and one has to make some ‘heroic’ assumptions about how the other species of gases and aerosols are emitted to assess climate change. If governments want more and better emission scenarios, they have to invest in it.

    2. We try to keep things transparent about the assumptions we are using. However, we can’t repeat these assumptions ad nauseum and will often refer readers back to where they have been stated earlier. Your point about the error in our (CSIRO) paper made earlier this year was noted. A request was immediately sent by a colleague through to the relevant people to correct and repost the document after you first pointed this out but it was not done (a production task). On the basis of your recent post pointing out that the phrase had still not been corrected (quelle horreur) we have asked that it be followed through. There is no conspiracy – it was a breakdown in process.

    3. Ok, I generally use the range of marker scenarios (e.g. 1.4 to 5.6 in 2100 using the IPCC 2001 range of sensitivity). It is slightly smaller than the full SRES range. There are two ways to use sampling in this range combined with climate projections and a known climate-impact relationship to assess impacts. One can produce a pdf of the output to assess most likely and least likely. It is generally a normal-type distribution with a peak in the lower center, skewed right because of the way the underlying uncertainties are combined. The other way is to assess the likelihood of exceeding a particular level of change that is associated with a critical impact. If one runs a risk analysis that looks at the likelihood of exceeding a specific threshold, the difference in the results are small compared to underlying inherent uncertainties.

    4. The new scenarios process is likely to produce scenarios that are used by the IPCC but that are not produced by the IPCC. International co-operation will be required to ensure this comes about.

    I think that a more detailed accounting of the differences between reference and policy scenarios may help undertake risk assessments. In particular, rather than a storyline approach, one takes the normative position of cheap energy / high growth shared by many people and instiutions and see how that plays out in terms of climate change.

    6. Hmmm, System of National Accounts. Have you, or any other experts, detailed precisely what these deviations are, and what material differences they would have on the results?

    In the end, it is the material differences that matter and that is what I am most interested in. Using the methods briefly described in my point 3 above, it would be possible to test how different forms of information would affect the outcomes of impact assessments (i.e. value of information methods of uncertainty analysis).

    Your post of the Hartley material is interesting. I am familiar with these arguments and think they have great deal of traction with those who are averse to perceived economic risks, and require a significant ‘burden of proof’ to take what they perceive as risky behaviour. If I can speak for JQ, our perceptions of the risks that climate change poses to a range of systems (economic, social, environmental) are such that learning by doing approaches on both adaptation and mitigation are required with our current level of knowledge. Mitigation and adaptation are not either/or, they are both, and the economy is sufficiently robust to be able to handle that.

    There are a range of points I could make on the Hartley statements but some of the work we are doing at present will hopefully address some of these in the near future. I think what proust sees as political motivation, I would characterise as risk perception and risk aversion to different aspects of the economy, society and environment. There is nothing sinister in this, after all, the climate debate always boils down to people’s values – it’s all about risk.

    Ian, I think you mischaracterise the approach of CSIRO Energy Transformed Flagship. Testing the cost-effectiveness of targets or of the feasibility of technologies that may be needed to reach a target is not a de facto endorsement of target setting policies, it is rather an exploration of what may be needed to avoid dangerous anthropogenic interference with the climate system. Policy setting is external to those assessments.

    I hope these point by points don’t bore the readership of this blog stupid, but hopefully inform folk of some of the complexities involved.

  15. Tom N.
    October 11th, 2006 at 10:36 | #15


    Don’t worry Roger (or Ian or Q) about “boring the readership”; this debate is better than the sex I had last night!

  16. Ian Castles
    October 11th, 2006 at 11:03 | #16

    Thanks again Roger. I agree it’s complex. My points in reply are:

    1. It was the Academies’ view, not the Academy’s (3 Academes, not one). Relevant economic expertise is a necessary but not sufficient condition to produce emissions scenarios. Of course the production of adequate emissions scenarios would have required investment by goveernments, but I wonder why it hasn’t been forthcoming?

    When the IPCC was considering the Castles & Henderson criticism of the SRES, Dr. John Mitchell wrote to the Chair of the IPCC on behalf of the Working Group on Climate Models, “which includes representatives of all the major climate modelling centres contributing to the Third Assessment Report”, to argue that “there is little scientific justification in running new scenarios since the resulting climate change outcome is unlikely to be indistinguishable (sic) from existing scenarios with similar radiative forcing. Hence the WGCM unanimously urge IPCC to retain the current SRES scenarios without change… We believe that it is better not to try and run new model experiments, but to stick to the scenarios used in the TAR.”

    That letter was tabled at the IPCC Bureau meeting in Geneva in December 2002, together with a paper from Australia’s John Zillman saying that “it is important that these criticisms of the economic basis of the SRES scenarios be addressed and the necessary clarifications as to the methodology made.” So we’ve ended up with exactly the situation that John sought to avoid ten years ago (He said at the meeting “Unless the issues are resolved quickly … the issue will surface through the economics/statistics communities of more and more countries and escalate into an interdisciplinary contrroversy which will continue to plague the credibility of the IPCC process through the AR4.

    2. Can you point me to a place where you’ve explained that the higher CSIRO warming projections depend on an assumption that the per capita use of electricity consumption in the entire developing world will be several times higher than in the richest countries of the world at present (or on some other combination of assumptions that produce an equivalent level of emissions from this and other sources)?

    3. Point taken. But see my earlier points about, e.g., the extremely low probability, if not impossibility, that new power stations could be constructed at several times the rate that is projected by the IEA. I know of no evidence that the realism of the higher scenarios has been tested.

    4. The IPCC has already done enormous damage to international cooperation in this area by its snubbing of the economic statistics community and its fatuous observation that “the economy does not change by using a different metrics (PPP or MEX), in the same way that the temperature des not change if you switch from degrees Celsius to Fahrenheit.” How would the climate science community react if half the EU countries reported their temperatures in Celsius and half in Fahrenheit? Yet the review reports to UNFCCC use PPP measures for some countries and MER measures for others (Germany uses MER so that it xcan claim to be the world’s third largest economy, but the report for the EU as a whole uses PPP).

    6. I am surprised by your question, given the extensive literature on the subject. Have you read the comment by Erwin Diewert on John Q’s submission to the Stern Review responding to the Castles and Henderson critique of the IPCC? There is noone better qualified to pronounce on this than Professor Diewert, and he says that the SRES projections should be re-estimated.

    But as the Australian Bureau of Statistics has the statutory responsibility for statistics, and the Act refers specifically to Australia’s relationship with international organisations in this connection, perhaps you should address the question to the ABS. You might also wish to read the Treasurer’s speech to the Lowy Institute in September 2005, which is available at http://www.treasurer.gov.au/tsr/content/speeches/2005/013.asp .

    I’m puzzled at your explanation that mitigation and adaptation “are not either /or, they are both.” If you mean that the response to climate change must include elements of both, who is disputing that? If you mean that you can spend the same dollar twice, that’s where the dismal science comes in. But no one gains as a result of lack of adequate anbd properly-based information. In my opinion, we are all the poorer as a result of the Working Group on Climate Models having had more clout in the IPCC than John Zillman and the Australian Government.

  17. Ian Castles
    October 11th, 2006 at 11:32 | #17

    Of course John Zillman sought to avoid this situation FOUR years ago (not ten). I’ve seen a draft of the relevant section of the Summary for Policymakers of the IPCC’s forthcoming Assessment Report, which cites ranges of temperature increase for several IPCC scenarios and says that they are “scenario dependent.”

  18. proust
    October 11th, 2006 at 14:03 | #18

    I think what proust sees as political motivation, I would characterise as risk perception and risk aversion to different aspects of the economy, society and environment. There is nothing sinister in this, after all, the climate debate always boils down to people’s values – it’s all about risk.

    I think that is a charitable point of view. Judging from your posts I’d say it is probably an accurate assessment of your own motivations, but the behaviour of the most visible AGW advocates bears all the hallmarks of a moral crusade, not that of dispassionatel risk assessment within some value system.

    When you have Greenpeace claiming almost every unusual weather event as evidence for global warming, Al Gore circumnavigating the globe on a chartered jet exhorting the rest of us to emit less (sorry, my mistake, it’s ok for Al because he can afford to buy carbon credits to offset his flatulance – only the proles actually have to reduce their emissions), and even Quiggin claiming singular rainfall outliers as evidence for AGW, it is very hard to believe that this is all about dispassionate risk assessment.

    No, this is about certain people wanting to impose their morality on the rest of us..

  19. jquiggin
    October 11th, 2006 at 16:03 | #19

    While we’re learning a lot about climate change in general, and I hope that this discussion continues, I’d like to stress again the main point of post, namely the low levels of flows in most recent years, culminating in the likely record low for 2006. We have no choice but to adapt to this, of course.

    As regards taking action to mitigate global warming, those who want to delay action have a pretty strong burden of proof on their side at this point. It’s necessary to provide a convincing argument that severe environmental damage can be avoided with deferred action. If anyone has provided such an argument, I haven’t seen it. I recall a general claim along these lines from Nordhaus, but that was around a decade ago, so a lot of the delay he was calling for has already happened.

  20. Ken
    October 11th, 2006 at 17:14 | #20

    Whilst there’s benefit, planning wise, in having good information and confidence in the projections of consesquences,(climatically, economically and geopolitically) they are always going to be imperfect yet that lack of perfection is not sufficient reason to fail to act. That there will be negative consequences to global warming and worse consequences if we (as individuals, communities, companies, nations and combined nations) fail to act with will on both mitigation and adaptation seems convincingly proved. Let’s start seeing an R&D effort in line with our concerns that can find and develop viable alternatives to ongoing and ever increasing CO2 emissions, be they as apparently obvious as better insulators, batteries or solar cells, or mundane as more efficient production methods, or grandiose as sequestration schemes or fusion reactors. The lack of absolute knowledge of climate science or the consequences of global warming ought not be the basis of holding back on doing things that ultimately are going to prove beneficial, whether the numbers err on the side of optimism or of pessimism.

  21. Ian Castles
    October 11th, 2006 at 18:13 | #21

    John, In the real world, all sorts of actions are being taken to mitigate global
    warming – or which, whatever the stated motivation, will have that effect. The IEA’s Alternative Scenario chapter lists scores of policies which the Agency considers that various countries are likely to adopt in the coming decades. The projected growth between 2000 and 2030 in global CO2 emissions from fuel combustion under this Scenario is much less than the growth in fossil fuel CO2 emissions under the B1 scenario and fractionally less than under the B1T scenario.

    The IEA projections assume that there will be a considerable increase in the proportion of the world’s population with access to electricity in their homes, which was 73% in 2000 (“World Energy Outlook 2002”, p. 397) and was projected to increase to 83% in 2030 (ibid, p. 377). The IEA has added a new module to its World Energy Model to generate projections of electrification rates from input assumptions on income, fuel prices, technological advances, etc. Most of the increase in electrification will be in urban areas where the provision of access to grids is relatively cheap. In most cases fossil fuel burning plants are the main source of supply to the grid.

    In the report in the “Canberra Times” on 9 October to which I have already referred, the 12 member agencies of the climate change roundtable to which the CSIRO has provided a report (including Caritas, Oxfam, Friends of the Earth, World Vision and Anglicord) said “more than 70 per cent of people did not have access to electricity” (I don’t know where that figure came from), and that “prioritising aid to install renewable energy would help leapfrog polluting technologies’ and help ‘developing countries to escape being caught in the fossil fuel investment cycle.”

    I haven’t studied the electrification projections in the more recent reports, but I’m sure that the projected fossil-fuel-based extension of electrification to the urban poor in many developing countries is allowed for in the Alternative Scenario. I’d like to see that extension take place and I fear that the practical effect of the prioritisation that the aid agencies may argue for on the basis of the report that the rest of us can’t see will work to the disadvantage of some very disadvantaged people. I’m certainly among those who’d want to delay this action and I don’t agree that a strong burden rests upon me on this point. I think the burden of proof is on those who propose these measures to provide some more rigorous analysis than has been produced to date.

    Roger says that the “main sources of uncertainty [in the CSIRO projections] are the emission scenarios themselves (produced by others)”. I think that this is a cop-out. I’m also unimpressed with aid agencies that use scary scenarios produced by others (and in which the whole world is assumed to become extraordinarily rich and use far more energy per head than the rich countries do today) to argue that “there are millions of people who will be forced to be continually on the move from … poverty caused by climate change.” I suspect the quality of the research that has gone into such conclusions.

  22. Roger Jones
    October 11th, 2006 at 18:32 | #22

    Back on topic, The Age had a terrific opinion piece from Tim Colebatch, economic staffer, on the big dry. He has captured the issue really well, in my opinion. We like it when journos frame the scientific issues this well.


  23. Ian Castles
    October 11th, 2006 at 18:48 | #23

    Roger, just back again briefly to the discussion that John said he hoped would continue. I forgot to comment on your suggestion that I had mischaracterised the approach of CSIRO Energy Transformed Flagship, because “Testing the cost-effectiveness of targets or of the feasibility of technologies that may be needed to reach a target is not a de facto endorsement of target setting policies, it is rather an exploration of what MAY be needed to avoid dangerous anthropogenic interference with the climate system” (EMPHASIS added).

    On the ABC Four Corners feature “What Price Global Warming?” on 28 August, Dr.John Wright, Head of the Energy Transformed Flagship said “The task IS absolutely immense. Can the world do it? Not without the sort of technologies we are trying to develop here.” These propositions are stated as facts, and the underlying assumption is that the world must reach the target set by the Energy Transformed Flagship if dangerous anthropogenic interference with the climate system is to be avoided. Does CSIRO believe that the B1T emissions profile, which projects a significant INCREASE in emissions between now and 2050, will lead to such an outcome?

  24. rog
    October 11th, 2006 at 19:35 | #24

    From the Colebatch article; Those who deny climate change have retreated to arguing that this too could be just one of the many variations of nature, missed by the historical records because 100 years is just a moment in time. They could be right, but who would base a policy on assuming that?

    It wasnt too long ago that Sydney Water raised the height of Warragamba Dam; a few years of seemingly continuous rain worried authorities that further downpours could breach the dam top breaking the dam wall down with the ensuing catastrophic flooding of many tens of thousands of homes in the Sydney Basin.

    They based their policy on the climate change at that time.

  25. Brian Bahnisch
    October 11th, 2006 at 21:53 | #25

    rog, for a number of years the Hinze Dam at the back of the Gold Coast was so low that water was being pumped from the Wivenhoe Dam to keep the Gold Coast going. Last summer they had half a metre of rain in one day which almost filled the dam.

    We’ve been having exceedingly dry seasons here in the April-September period, including the driest on record, from memory, in 2004. But in 1995 we had over 800mm in 8 days in April-May.

    My brother told me about a dam somewhere in central Qld that had a jetty high and dry for so long that there was a tree (he said 30ft high) growing next to it. Yet a couple of years ago during generally dry years it filled.

    Just sayin’.

  26. Mike Hart
    October 11th, 2006 at 23:04 | #26

    I am curious as to why in the posited solutions no one appears to raise the issue of the effect of ecological degradation, vis a vis loss of vegetation and forests world wide and the ever increasing numbers of human beings on this planet, in the context of a possible immediately available solution that does not rely on finding some new technological fix, that is plant trees. I do understand there is work going on to determine if grass (ergo, cropping) does the same job as trees but have heard no more about it.

    Just to take another curious coincidence, why is it that no matter what data I see it appears that the mid 1970’s appeared to be some form of tipping point, which coincidentally was when world population passed 3 billion.

    And as a random observation, as a professional aviator I monitor wind, cloud and temperatures constantly, day in day out. I have found it increasingly difficult to reconcile some days the metereological theory I learnt with the weather conditions I see daily. In particular rather steep isolated temp gradients with pooled inversions which have a distinct local regional character, the lapse rate I see most often and have done for some time is the dry adiabatic lapse rate. I also encounter quite severe layers of chop (atmospheric mixing) at various levels and in stratas. Cloud formation seems relatively normal when its present but the water droplets are so fine that I can fly through the stuff for hours with hardly a trickle of any form of moisture of the windscreen. The level of lower level atmospheric churn has increased and even the cumulonimbus despite all the energy supposedly available does not achieve the same heights and intensity (more wind and lightning and less rain and hail). Even the cyclones encountered and I have been around for just about all of them for the past decade, have less water, plenty of wind energy and build and die very quickly compared to the past, well in Australia anyway. In short I have doubts about some of the so called atmospheric models, that’s all.

    Just a few queries.

  27. Tam O’Shanter
    October 11th, 2006 at 23:53 | #27

    JQ said: We’re talking about a gross output loss of perhaps 3 per cent by 2050, an effect too small to notice even against the background noise of the medium-term macro cycle.

    Actually Nordhaus has had more to say more recenly than JQ’s “decade or so ago”. In his book (with Joseph Boyer), Warming the World, Economic Models of Global Warming, MIT 2000, his model indicates that with warming of 2.5C by 2100, the costs would be “around 1.9% of global income” (p.96). With your costs at 3% (down 40% from your July estimate of 5%), the benefit:cost ratio is less than one, not good allowing for the time lag between emissions abatement and reduced warming (even worse for USA, Japan, Russia and China for which he estimates zero damages by 2100) What is your model’s estimate of the B:C ratio for these countries and globally?

    Nordhaus is a true believer in AGW, but concludes (167): “..the strategy behind the Kyoto protocol has no grounding in economics or environmental policy…the benefit:cost ratio for the Annex 1 (trading system) is 0.44….the United States is a net loser”

    Until more cogent arguments are developed to refute Nordhaus than are as yet available from JQ or anybody else, BAU seems indeed to be the best bet, albeit BAU with the ongoing current adjustments to rising energy costs.

    Regards to all


  28. jquiggin
    October 12th, 2006 at 06:46 | #28

    TOS, this is a different question to the one I mentioned, but you don’t need to wait for a refutation. Nordhaus’ estimates of the environmental cost of warming are way too low, and he puts too little weight on low-probability extreme outcomes. I made this point in detail in my submission to the Stern Review recently. You can read the PDF here. Nordhaus also fails to take appropriate account of adjustment costs, as John Horowitz and I pointed out in the American Economic Review back in 1997.

    Nordhaus’ opposition to Kyoto is not shared by the majority of economists.

  29. Brian Bahnisch
    October 12th, 2006 at 08:41 | #29

    TOS, Hansen estimates the equilibrium sea level response of 3C warming at 25m, plus or minus 10 metres, not by 2100, but eventually. He also indicates that such an increase would inundate 703 million people in the US, China/Taiwan, Japan, India/Sri Lanka, Bangladesh, Indonesia/Malaysia and Western Europe (2000 population figures). This does not include Vietnam, Egypt, the Pacific, the Caribbean or South America.

    I think there is a clear case for the precautionary principle to apply.

    If you want a really scary scenario try this one from Andrew Watson, Professor of Environmental Science University of East Anglia:

    The Earth has been, broadly speaking, cooling over the last 50 million years and we are going to push it back into a very much warmer state. Is it going to be stable? That’s a very good question. I don’t know the answer to that. The fact is that the last time we had high levels of carbon dioxide in the atmosphere was 100 million years ago and the Sun was a little bit cooler at that time. Now if we push it up…this is not something that most climatologists will talk about but I think that there is a small chance, maybe a 1% chance, that if we really hit the planet too hard we may push it into a runaway system in which the temperature simply goes up and up until the oceans boil into the atmosphere, and that would extinguish all life on Earth. (Emphasis added)

    Annamaria Talas, who produced the ABC RN program this quote came from, said here that the statement was speculative and came from computer modelling. But it was not off the top of his head. Talas said:

    Watson believes we are all here because of a series of fortunate events that were just right for life to emerge and warns that things are getting more and more difficult even without human forcing, so please hands off! The system is unstable.

    At 1% the risk for such a scenario seems rather high to me. I’m a chicken. It’s enough for me to want to apply the brakes firmly and hope the planet let’s us off with a warning. Others may wish to sip their champagne on the deck and wait for the science, oblivious to the waterfall that may be just around the corner.

    Or can someone assure me that Watson is a hopeless goose.

  30. tam o’shanter
    October 12th, 2006 at 12:39 | #30


    October 12th, 2006 at 6:46 am
    “TOS, Nordhaus’ estimates of the environmental cost of warming are way too low, and he puts too little weight on low-probability extreme outcomes.” That sounds Irish, low probs require low weights.
    “… Nordhaus also fails to take appropriate account of adjustment costs, as John Horowitz and I pointed out in the American Economic Review back in 1997.” You mean 1999 I think, and your Stern submissions should have mentioned the response by Mendelsohn & Nordhaus questioning the substantive effect of your correction.
    Your revised Stern submission is good, but still has some defects. I really think you should run the Nordhaus-Boyer RICE/DICE model with your preferred assumptions; meantime I think your Stern submission depends too much on the transport sector, leaving out the the rest of energy demand as well as the free rider question, or will we bomb China into signing up to Kyoto when they refuse on the basis of the Nordhaus model showing they have nothing to gain from it? How high will your carbon tax have to be to get a perceptible REDUCTION in energy demand, when the current $200 per tonne implied by oil going from $30 to $60 a barrel has signally failed to effect more than a slowing of the rate of increase in demand (and that has yet to be reflected in CO2 growth as measured at Mauna Loa).

    Meantime I await with interest the ALP’s election platform next year proposing either a doubling of fuel costs to get a REDUCTION in emissions or failing that a hike in GST to 18% to cover your claim to Stern that we are all willing to pay 5% of our income for the sake of preserving bio-diversity. What I am saying is that marginal adjustments to fuel use will not deliver the 60% cut in total emissions that you seek, and that electorates are unlikely to sign up to more.

    Your comment that “Nordhaus’ opposition to Kyoto is not shared by the majority of economists” had no source. Has there been a poll? I suspect at least as many if not more sent hostile comments to Stern as supportive like yours – I’ll do a count when I get back from tennis.



  31. tam o’shanter
    October 12th, 2006 at 16:35 | #31

    JQ: I counted 13 economists who made submissions to the Stern review that were critical of Kyoto (and I counted Julian Morris only once), and two that were supportive, of whom you were one. I note that at least one of Australia’s other top economists, Warwick McKibbin, is also a well known critic of Kyoto. What’s your tally? Interestingly, most of the engineers were strongly critical.

  32. jquiggin
    October 12th, 2006 at 21:11 | #32

    Back in 2002, about 250 Australian academic economists (around 40 per cent of the profession) signed a petition supporting Kyoto. A counter-petition was organised, but IIRC, never released because the number of credible signatories was embarrassingly small. The Australian exercise was based on a similar one in the US.

    Warwick’s opposition to Kyoto is based on the fact that he has his own plan, which he believes to be more politically salable. He may be right, and, if he can secure substantial international support I don’t see any big problems with his plan as against Kyoto. But so far, he hasn’t got very far with the idea.

  33. Brian Bahnisch
    October 12th, 2006 at 22:06 | #33

    “TOS, Nordhaus’ estimates of the environmental cost of warming are way too low, and he puts too little weight on low-probability extreme outcomes.� That sounds Irish, low probs require low weights.

    TOS, the word you are not attending to is “extreme”. I can see you’re not impressed with my rantings about Hansen’s concerns over sea-level rise or Watson’s concerns about a 1% chance of the sea boiling dry.

    Alan Dupont and Graeme Pearman have a chapter on ‘Wild cards and abrupt climate change’. “Abrupt’ in climate terms is defined as ten years. They identify the following:

    1. Collapse of the thermohaline circulation.

    2. Melting glaciers/ice-sheets and permafrost.

    3. Forests becoming a carbon source rather than a carbon sink. (They don’t mention it but the possible collapse of the Amazon rainforest comes to mind.)

    4. Aerosols masking the underlying warming trend.

    Tim Flannery adds another one – the release of methane from ocean clathrates.

    Dupont and Pearman say:

    Even if the probability is low, it is far from zero, and as the potential impact could be very high indeed policy makers ought to factor them into their security calculations and alternative futures planning.

    Their focus is security, of course, but they point out early on that the best form of mitigation is to reduce carbon outputs.

  34. Brian Bahnisch
    October 12th, 2006 at 22:09 | #34

    Mike Hart, what you said about changes in the weather is a worry, although I don’t know enough meteorology to fully appreciate it.

    I wonder whether the Asian brown cloud has something to do with the ‘dry’ cloud especially but other effects as well. (Links to CNN,
    Asian Development Bank and NASA articles.) I understand that aerosols are not well understood in climate science but that they do have an effect on droplet formation.

    On cyclones, I’ve noticed that they seem to be staying north more often in relation to Queensland, re-forming and travelling west and often finally breaking down when they hit the coast of Western Australia. Alternatively they track south towards New Zealand, but this was always a usual path. The bottom line is that none seem to form a rain depression that brings soaking rain to central and southern Qld. We used to benefit a lot from such rain depressions in the past, including run-off into dams.

  35. gordon
    October 13th, 2006 at 12:12 | #35

    Tam O’Shanter may not be aware that Nordhaus prefers a carbon tax to the Kyoto trading proposal. He is joined in his opposition to the Kyoto trading proposal by a lot of greenies, (for example the new Dag Hammarskjold Foundation publication “Carbon Trading; A Critical Conversation…”) mostly on the grounds that the “offsets” mechanism included in the Kyoto proposal is unworkable.

    Economists may argue for and against carbon tax/trading mechanism and forget about command and control on the grounds that it is inefficient. We are getting to the point where, as in wartime, efficiency is rendered irrelevant by the need to survive.

    And Brian Bahnisch may be interested in this ABC News item about the effects of particulates on rainfall.

  36. Brian Bahnisch
    October 13th, 2006 at 22:35 | #36

    gordon, thanks for that link. It adds to stuff I have read recently about particulates and the Sierra and SE Qld. Both mention the work of Israeli cloud physicist Daniel Rosenfeld.

    Today on Newsradio I heard again a reference to the ozone hole affecting wind patterns leading to drier weather in Australia.

    Mike Hart mentioned world population and the 3 billion mark in the mid 1970s as some kind of tipping point. I recall Ronald Wright in his Massey lectures A Short History of Progress saying that around that time (or maybe the 1980s) we started to use the planet’s resources unsustainably. Al Gore pointed out that in the 100 years from when he was born in 1948 the population will have gone from 2 billion to 9 billion.

    Some bright spark was saying today on Radio Netherlands that if we made medical discoveries in the next century equivalent to what we did in the last with positive effect on longevity we’d be in serious trouble with a population of 10-15 billion.

  37. Brian Bahnisch
    October 13th, 2006 at 22:45 | #37

    btw you’d think the Geshem Project method of making rain might be worth a go around urban dam catchment areas if cloud seeding doesn’t work. If I understand it rightly you don’t even need clouds as such to begin with.

  38. Mike Hart
    October 14th, 2006 at 20:46 | #38

    For what its worth, clouds form when water molecules almost in gaseous form attach themselves to particulate matter in the atmosphere, smoke particles, soot, pollen whatever. I understand a major study in the Indian Ocean (mentioned on the ABC 4Corners program on Global Dimming) appeared to establish that increased pollution actually led to less rain and peculiarly less sunlight. The post 9/11 data on the massive 1 degree C rise in US temps without jet contrail cover seemed to indicate that even if we stop burning fuels and reduce our pollutants then that stored heat will bounce back substantially. A lot of people do not seem to understand the fact that to raise water or atmospheric temps even by one degree requires a massive amount of energy. To contemplate a 2 or 6 degree rise suggests massive amount of heating. The issue of CO2 is merely one of the gases that form the atmosphere. I am sure that solar sunspot cycles are also partly to blame as the latest UNE research suggests.

    To my mind you can argue about the technicalities of statistical methodology, modelling and whatever to attempt to arrive at a rational reasoned policy platform but sometimes like weather forecasting a good look out the window will tell you more! Every time you cut down a tree you release stored carbon, every time you burn fossil fuel you release stored carbon, every time you cut down a tree you reduce the grounds ability to store water and every time you burn fuel you release heat, you do not have to be a scientist to realise that is not a sustainable cycle. Trouble is with most of our population living incarcerated in airconditioned thermally cushioned dwellimgs in a limited number of geographical areas we therefore take the environment and what is happening for granted and it is poorly understood by most. It is the frog in the pot syndrome, the water is close to boiling, Welcome to the ‘Long Emergency’.

    Sadly despite the good intentions of many of those who post here I see absolutely no evidence that those making policy and governing actually understand the fact that we are now in crisis already and it is going to take a massive community effort to change what we do, where we do it and how.

  39. tam o’shanter
    October 14th, 2006 at 21:49 | #39

    Mike Hart said: Every time you cut down a tree you release stored carbon,…. every time you cut down a tree you reduce the grounds ability to store water.

    Nonsense! The wood furniture and window frames etc in my house not to mnetion the books are all still stored carbon. And if cut down trees are replanted, despite the best efforts of Greenpeace, the ground’s abilty to store water is not impaired.

    As for the JQ belief that global warming means falling rainfall, see the CSIRO report (11 October) for the ACF and Greenpeace mob (Climate Change and Development Roundtable) which predicts massive increases in rainfall in Asia Pacific region generally.

  40. Brian Bahnisch
    October 14th, 2006 at 23:31 | #40

    You can download the report from here.

  41. Mike Hart
    October 16th, 2006 at 08:08 | #41

    Tom, I take your point about timbers use for construction and various artifacts but you off the mark about where the trees go. For example, in the Amazon it is burnt as a result of land clearing, and the majority of vegetation loss in this country has been for the same reasons. As far as I can see there has not been much replanting anywhere which is why the data on tree and vegation cover world wide shows and inexorable decline year by year. Finally the wastage of timber during harvesting, milling, transport, and end use is substantial. As for water retention, then if your right then I guess nearly every agricultural expert on land management has it wrong.

  42. jquiggin
    October 16th, 2006 at 08:11 | #42

    Tam, read the posts and threads and you might be able to see why your point is irrelevant.

  43. wilful
    October 16th, 2006 at 15:01 | #43

    Sadly despite the good intentions of many of those who post here I see absolutely no evidence that those making policy and governing actually understand the fact that we are now in crisis already and it is going to take a massive community effort to change what we do, where we do it and how.

    Funny about that, since it has been virtually the sole efforts of bureaucrats and those on the public purse that has given us any awareness of the issue in the first place.

  44. tam o’shanter
    October 17th, 2006 at 13:02 | #44

    Mike Hart: go to the FAO, SELECTED CURRENT
    ISSUES IN THE FOREST SECTOR, Table 2 p.134. For example, the annual loss of tree cover across Asia was a trivial 0.1% p.a. between 1990 and 2000, somewhat offset by an equal % increase in Europe. Australia’s reduction in forest area was 0.2% p.a., but it’s not clear if this refers to both primary forest and plantations.
    In the Amazon, the cleared areas are apparently planted to soya or pasture, which also absorb CO2 on a recurrent annual basis.
    You might be surprised to know how little wastage there is in a well managed timber yard – e.g. chips to spread as weed prevention in suburban gardens are not cheap so there’s every incentive to collect and sell them.



  45. Chris O’Neill
    October 18th, 2006 at 01:17 | #45

    “In the Amazon, the cleared areas are apparently planted to soya or pasture, which also absorb CO2 on a recurrent annual basis.”

    That’s handy, recurrent absorption of CO2 which would require that they store the soya permanently.

    “You might be surprised to know how little wastage there is in a well managed timber yard – e.g. chips to spread as weed prevention in suburban gardens are not cheap”

    That’s right, they’re not cheap at the shop. But I wonder why they need to be replaced every couple of years. I wonder what happens to the old ones?

  46. tam o’shanter
    October 18th, 2006 at 07:59 | #46

    Chris: We eat the soya one way or another and then a new crop is planted; or would you prefer population reduction programmes to take care of the CO2 we exhale? the old chips form an excellent mulch, improving the soil for more CO2 absorption by fruit and vegetables. But the main point is that major emission reduction will entail proportionate reductions in energy use in the absence of meaningful carbon free production from nuclear. Solar involves large reductions in surface area available for other use, wind can apparently not make much more than a marginal contribution, especially in places like Mt Rodgers where wind speed has averaged less than 5 km per hour for the last 3 months (you need 50 for power).

  47. Chris O’Neill
    October 20th, 2006 at 01:46 | #47

    “Soya also absorb CO2 on a recurrent annual basis”

    The point is that replacing rainforest with soya crops involves a permanent reduction in the amount of carbon that is stored in vegetation. Considering how much carbon is stored in rainforest, this is not insignificant.

    “the old chips form an excellent mulch”

    You still haven’t answered the question, what happens to the old chips that need to be replaced every couple of years?

  48. jquiggin
    October 20th, 2006 at 07:09 | #48

    Chris, it’s best not to feed the trolls by arguing with Tim/Tam. You won’t get anywhere.

  49. tam o’shanter
    October 20th, 2006 at 11:40 | #49

    Chris: 1. Most timber products other than firewood are embodied carbon and never release any CO2.
    2. Logged forests can be and are usually replanted except so far in the Amazon.
    3. Wood chips used in gardens do decompose and release CO2 but also improve the soil thereby allowing stronger future plant growth (as in my wife’s vegie patch) and enhanced CO2 absorption. The net effect could well be positive CO2 absorption. For references to a large literature on all this see M.R. Shaw et al in Ehleringer et al, Springer 2005. C.D. Keeling et al in the same book conclude: ” Our principal finding from this analysis of atmospheric CO2 data is that interannual fluctuations in net exchange of CO2 are of the order of several Pg C yr^-1 and correlate with strong El Nino events” (110). This paper also implies (106) that cyclical events such as droughts like the current which are also associated with el Nino have more to do with the fluctuations mentioned by Keeling than with the secularly rising trend in industrial CO2 emissions. Their Fig. 5.4 compares rates of change in CO2 at Mauna Loa with the ENSO.

  50. tam o’shanter
    October 20th, 2006 at 11:48 | #50

    JQ: did you see the BoM rainfall map in today’s Oz for 1 Oct 96 to 30 Sep 2006, showing c80% of the landmass with average or much more than average rainfall, and that really only the latte belt has had record lows?

    woof woof


  51. January 6th, 2007 at 09:31 | #51

    I visited this discussion to get some insight into the drought in Australia and had no idea what a hot-button issue this was in terms of whether the drying has been intensified by AGW. As someone who believes and has written that climate change looms as an enormous threat (but would love to be proved wrong), I’d like to offer just a couple of thoughts. Regardless of the AGW signal in the current drought, there is strong consensus that human-sourced emissions are contributing to many of the dramatic climate changes we are seeing throughout the rest of the world. Consequently, whether this drought is an artifact of AGW should be irrelevant to whether Australia should take action on climate change (unless one is prepared to challenge the entire suite of evidence that humans are affecting climate). Second, it is what happens in the US and Asia that will determine whether Australia becomes a victim of global warming, and not what Australians can do to reduce their own emissions. With its world-class scientists, engineers, and Australia, however, could have a huge global impact on the problem through the development on new technologies,market devices, understanding the science, and adaptive measures. To grab that role, however, its scientific and political leadership have to get past the discussion of whether to do anything at all.
    One last point: I simply don’t understand the argument that we’d be better off waiting twenty years to do something because we’d be richer and reducing C02 would be cheaper. We just had a world record year for C02 emissions, and as Socolow at Princeton has pointed out, every year we wait means that much more we have to take out later to stabilize emissions. Moreover, we are almost assuredly heading for a doubling of C02 (uncharted territory for as long as we’ve been a species), and have no idea whether somewhere between now and then we will cross some tipping point at which climate change becomes irreversible (and impoverishes us all).

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