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You are here: Home / Climate Science / A warning from Copenhagen

A warning from Copenhagen

21 Jun 2009 by Stefan

Translations: (Deutsch) (Chinese (simplified)) (Español)
Deutsch Chinese (simplified) Español

In March the biggest climate conference of the year took place in Copenhagen: 2500 participants from 80 countries, 1400 scientific presentations. Last week, the Synthesis Report of the Copenhagen Congress was handed over to the Danish Prime Minister Rasmussen in Brussels. Denmark will host the decisive round of negotiations on the new climate protection agreement this coming December.

The climate congress was organised by a “star alliance” of research universities: Copenhagen, Yale, Berkeley, Oxford, Cambridge, Tokyo, Beijing – to name a few. The Synthesis Report is the most important update of climate science since the 2007 IPCC report.

So what does it say? Our regular readers will hardly be surprised by the key findings from physical climate science, most of which we have already discussed here. Some aspects of climate change are progressing faster than was expected a few years ago – such as rising sea levels, the increase of heat stored in the ocean and the shrinking Arctic sea ice. “The updated estimates of the future global mean sea level rise are about double the IPCC projections from 2007”, says the new report. And it points out that any warming caused will be virtually irreversible for at least a thousand years – because of the long residence time of CO2 in the atmosphere.


Perhaps more interestingly, the congress also brought together economists and social scientists researching the consequences of climate change and analysing possible solutions. Here, the report emphasizes once again that a warming beyond 2ºC is a dangerous thing:

Temperature rises above 2ºC will be difficult for contemporary societies to cope with, and are likely to cause major societal and environmental disruptions through the rest of the century and beyond.

(Incidentally, by now 124 nations have officially declared their support for the goal of limiting warming to 2ºC or less, including the EU – but unfortunately not yet the US.)

Some media representatives got confused over whether this 2ºC-guardrail can still be met. The report’s answer is a clear yes – if rapid and decisive action is taken:

The conclusion from both the IPCC and later analyses is simple – immediate and dramatic emission reductions of all greenhouse gases are needed if the 2ºC guardrail is to be respected.

Cause of the confusion was apparently that the report finds that it is inevitable by now that greenhouse gas concentrations in the atmosphere will overshoot the future stabilization level that would keep us below 2ºC warming. But this overshooting of greenhouse gas concentrations need not lead temperatures to overshoot the 2ºC mark, provided it is only temporary. It is like a pot of water on the stove – assume we set it to a small flame which will make the temperature in the pot gradually rise up to 70ºC and then no further. Currently, the water is at 40ºC. When I turn up the flame for a minute and then back down, this does not mean the water temperature will exceed 70ºC, due to the inertia in the system. So it is with climate – the inertia here is in the heat capacity of the oceans.

From a natural science perspective, nothing stops us from limiting warming to 2ºC. Even from an economic and technological point of view this is entirely feasible, as the report clearly shows. The ball is squarely in the field of politics, where in December in Copenhagen the crucial decisions must be taken. The synthesis report puts it like this: Inaction is inexcusable.

Related links

Press release of PIK about the release of the synthesis report

Copenhagen Climate Congress – with webcasts of the plenary lectures (link on bottom right – my talk is in the opening session part 2, just after IPCC chairman Pachauri)

Nobel Laureate Meeting in London – a high caliber gathering in May that agreed on a remarkable memorandum which calls for immediate policy intervention: “We know what needs to be done. We can not wait until it is too late.” The new U.S. Energy Secretary Steven Chu participated over the full three days in the scientific discussions – how many politicians would have done that?

Filed Under: Climate Science, Reporting on climate

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416 Responses to "A warning from Copenhagen"

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  1. Hank Roberts says

    7 Jul 2009 at 5:53 PM

    Here’s the press release for the report Derek mentions:

    http://www2.lse.ac.uk/ERD/pressAndInformationOffice/newsAndEvents/archives/2009/07/climate%20poliyc.aspx

    Brief excerpt follows:

    … a strategy to avert an otherwise imminent failure in climate policy is being published by the London School of Economics and Political Science’s Mackinder Programme and the Institute for Science, Innovation & Society at the University of Oxford today (Tuesday 7 July).

    How to Get Climate Policy Back on Course argues that the only policies that will work are those which focus directly on improvement in energy efficiency and the decarbonisation of energy supply (called the “Kaya Direct” Approach in the report) rather than on emissions, which is an outcome of these processes.

    Professor Gwyn Prins from LSE and the report’s coordinating author said: ‘Worthwhile policy builds upon what we know works and upon what is feasible rather than trying to deploy never-before implemented policies through complex institutions requiring a hitherto unprecedented and never achieved degree of global political alignment.’

    The report argues that the recent Japanese ‘Mamizu’ climate strategy is the world’s first to start down this real world course in sharp contrast to the EU Emissions Trading Scheme, the UK Climate Change Act and the US Waxman-Markey cap-and-trade legislation. Professor Steve Rayner, Director of InSIS at the University of Oxford, said: ‘The world has centuries of experience in decarbonising its energy supply and Japan has led the world in policy-driven improvements in energy efficiency. These are the models to which we ought to be looking.’

    The paper’s twelve co-authors come from leading research institutes in Europe (England, Germany, Finland), North America (Canada, USA) and Asia (Australia, Japan). ….

  2. Doug Bostrom says

    7 Jul 2009 at 7:12 PM

    #400 Derek (and thank you Hank for importing the link):

    My prediction is that if this policy suggestion shows signs of spreading its infection, it will cost the fossil fuel industry more lost sleep. As well, quite a bit of money for the work of hastily constructing a whole new counterargument for why stasis is the most prudent course to adopt, or rather maintain.

    It may be impossible for PR professionals to concoct a self-consistent set of rationales explaining why this scheme as well as C&T will equally threaten to eviscerate the middle class, bring industry to its knees and end modern life as we know it. The stress of simultaneously supporting wildly disparate sets of reasons for inaction may well result in straining their PR beyond elasticity, opening further gaps in their logic.

    I’m sure the flacks are even now beginning preliminary work on this challenging task.

    Meanwhile, leaving aside the fossil fuel industry’s increasing level of anxiety over their cash fountain, we are reminded that changes in our own habits and redirection of our industrial capacity can actually result in beneficial change. For the general industrial world, it directs attention to new markets as well the opportunity to expand existing markets. For the world of energy consumers, a refocus of attention on conservation and more intelligent consumption is an unalloyed good.

    A bit more, from dotearth:

    Lessons from Japan: An international group of analysts focusing on climate policy says we can look to Japan for lessons in how policies can accelerate a move away from carbon-heavy fuels and toward more efficient use of energy. The authors, led by Steve Rayner of Oxford University and Gwyn Prins of the London School of Economics (known for a provocative critique of the Kyoto Protocol), say the last thing one would do is invent layers of regulatory bodies requiring international accord and transparency in arenas like energy policy, where countries traditionally go it alone. As Professor Prins put it in a statement, “Worthwhile policy builds upon what we know works and upon what is feasible rather than trying to deploy never-before implemented policies through complex institutions requiring a hitherto unprecedented and never achieved degree of global political alignment.” Japan has come under criticism from some environmentalists, particularly in Europe, for its approach to the next steps under a climate treaty. But the country has stood by its policies, given the name “Mamizu,” which translates to “ genuine clear water.” The approach is based on what can clearly be accomplished, rather than relying on indirect strategies for cutting emissions or boosting energy efficiency, including trading systems for emissions credits.

    http://dotearth.blogs.nytimes.com/2009/07/07/more-ideas-for-breaking-climate-deadlock/

    Details on “Mamizu” here, from the horse’s mouth:

    http://www.kantei.go.jp/foreign/asospeech/2009/06/10kaiken_e.html

  3. MikeN says

    7 Jul 2009 at 10:01 PM

    G Elliott, perhaps you have to first get climate scientists to understand this. Too many times you hear them or posters on this blog lauding China for boosting its renewable share, when her coal capacity is rising too.

  4. MrPete says

    7 Jul 2009 at 10:23 PM

    Re: Hank (#399) — go up a couple of comments (to #101, the one Moore is referring to in the #104 comment you quoted). He says:

    Re: 100. Yes you are correct – usually, as aslak Grinsted [#26] says the non-linear trend filter is close to triangular, and is very similar to the result of low pass filtering with a period of 2M-1.
    You asked why we did not point out this in the original paper – the answer is we were not aware (in 2005) that it was so commonly essentially a triangular filter.

  5. dhogaza says

    7 Jul 2009 at 11:31 PM

    G Elliott, perhaps you have to first get climate scientists to understand this. Too many times you hear them or posters on this blog lauding China for boosting its renewable share, when her coal capacity is rising too.

    In other words, we must condemn them for not being perfect, because we are, of course.

  6. James Lane says

    8 Jul 2009 at 12:58 AM

    Hank Roberts says:

    Last note from Moore I can find says:

    ~climateaudit.org/?p=6473#comment-348236

    “… If you strongly think its actually 21 years then please do go ahead and contact the editors. I have not followed this argument at all, so if if I wrote I would be simply quoting your own findings anyway.”

    Earlier (comment 104) Moore said:

    Re 102. I just looked at the synthesis report and I am not sure that they have even used the method we are talking about – the caption just says 15 year smoothing was used. The Eos paper was not referenced at all in the report. If you are so sure that he used the SSA method with M=11, why don’t you contact the publishers yourself? I certainly hope that if they have used M=11 that they change the caption to 21 year smoothing.

  7. PaulM says

    8 Jul 2009 at 7:07 AM

    Stefan, the caption is incorrect. It says ‘smoothed over 15 years’. There is no possible ambiguity of interpretation of this. 29 years are involved in your smoothing, so it should say ‘smoothed over 29 years’.

    [Response: I think we have to agree to disagree here. It is quite common to characterise filters by their half-power width (as is indeed very familiar for Gaussian filters), since this is more informative about their response than citing the number of points involved in the calculation. -stefan]

  8. Doug Bostrom says

    8 Jul 2009 at 12:10 PM

    Further to the London School of Economics report, news of G8 failure to progress on climate accord:

    “The world’s major industrial nations and emerging powers failed to agree Wednesday on significant cuts in heat-trapping gases by 2050, unraveling an effort to build a global consensus to fight climate change, according to people following the talks.”

    http://www.nytimes.com/2009/07/09/world/europe/09prexy.html?_r=1&hp

  9. Mark says

    8 Jul 2009 at 3:33 PM

    “[Response: I think we have to agree to disagree here. It is quite common to characterise filters by their half-power width (as is indeed very familiar for Gaussian filters),”

    Indeed, Physics abounds with FWHM measurements of the width of a bandpass.

    Full

    Width

    Half

    Maximum

  10. Magnus Westerstrand says

    10 Jul 2009 at 7:45 AM

    If some one that was there could help me to grasp the last part of
    P01.09
    Recent global sea level acceleration started over 200 years ago?
    Svetlana Jevrejeva(1), J Moore(2), A Grinsted(3), P Woodworth(1)
    http://www.iop.org/EJ/article/1755-1315/6/1/012026/ees9_6_012026.pdf?request-id=9ccc45a6-0072-4013-892a-d117fc28a7bc

    “If the conditions that established the acceleration continue, then sea level will rise 34 cm over the
    21st century. Long time constants in oceanic heat content and increased ice sheet melting imply that the
    latest Intergovernmental Panel on Climate Change (IPCC) estimates of sea level are probably too low.”

    Is it saying that IPCC probably have underestimated sea level rice (as I think) or is it saying something else?

    Might give a hint:
    http://www.agu.org/pubs/crossref/2006/2005GL024826.shtml

    I would be grateful…

  11. Martin Vermeer says

    10 Jul 2009 at 8:35 AM

    Magnus, a complicated story. Read the full paper:

    http://www.glaciology.net/Home/PDFs/jevrejeva_GRL08_recent_sea_level_acc_started_200yrs_ago._pdf.pdf?attredirects=0

    I don’t precisely understand it either.

  12. Magnus Westerstrand says

    10 Jul 2009 at 1:42 PM

    Thanks Martin, It seems clear that she means that IPCC underestimates… however, how trustworthy an extrapolation by constant acceleration is… is… I guess debatable. For one thing it seams like the deviations gets smaller closer to today… what would that do with the analysis?

  13. Charlie says

    11 Jul 2009 at 5:52 AM

    I have found 3 different versions of the Copenhagen Synthesis Report on the web. The Adobe file properties window shows modified dates of 6/17, 7/1, and 7/7/2009. climatecongress.ku.dk is the 7/1 modified version.

    Is there any sort of version number, errata, or change record on this report?

    Is there any way of telling versions apart other than looking at Adobe file properties?

    How would I know if the version I’m using really is the latest version?

  14. Phil. Felton says

    11 Jul 2009 at 9:55 AM

    Re #409
    Mark says:
    8 Jul 2009 at 3:33 pm
    “[Response: I think we have to agree to disagree here. It is quite common to characterise filters by their half-power width (as is indeed very familiar for Gaussian filters),”

    Indeed, Physics abounds with FWHM measurements of the width of a bandpass.

    Full

    Width

    Half

    Maximum

    Agreed, it’s standard practice in optics when describing the bandwidth of optical filters.

  15. Hank Roberts says

    11 Jul 2009 at 11:05 AM

    Charlie, Google finds lots more copies of the file than just three.
    It’s always a mistake to copy rather than point, but people do it a lot.

    If you point to the actual links you’re wondering about people can look.

    If you ask the people at the official site, they can identify the current version.

    If you have Acrobat Pro (not ‘Reader’) it has a Compare PDFs tool.

  16. Hu McCulloch says

    20 Jul 2009 at 3:10 PM

    RE #407,

    PaulM says:
    8 Jul 2009 at 7:07 am

    Stefan, the caption is incorrect. It says ’smoothed over 15 years’. There is no possible ambiguity of interpretation of this. 29 years are involved in your smoothing, so it should say ’smoothed over 29 years’.

    [Response: I think we have to agree to disagree here. It is quite common to characterise filters by their half-power width (as is indeed very familiar for Gaussian filters), since this is more informative about their response than citing the number of points involved in the calculation. -stefan]

    I find your recommended half-power period for the SSA filter using M = 15 (29 weights) to be 45.9 years. The half-amplitude period, which is perhaps more useful outside of electronics, is still 33.0 years. See graphs of the amplitude response here.

    Wouldn’t it then be more appropriate to call your filter 33- or 46- year smoothing, depending on the measure, rather than 15? Or do you get different values?

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