Questions for Lord Turner of the Climate Change Committee

following the APPCCG meeting of 2nd July 2008

PARTS 1 and 2

1. Climate science

The IPCC fourth report clearly underestimates the pace of climate change. For example it estimated that the first disappearance of summer sea ice in the Arctic would happen around 2050. This now seems likely in the next few years. The IPCC predictions were based on runs of computer models, which omitted important climate feedbacks. Lord Turner mentioned there are different views regarding the extent of the IPCC AR4's underestimate.


1.1 The disappearance of Arctic sea ice could be regarded a milestone in climate change to assess the accuracy of predictions. Are there other milestones that are significant?

1.2 What improvements have been made to the computer models that predict climate change? Has the Hadley Centre yet incorporated methane from melting tundra in it's models.

1.3 Lord Turner mentioned that some experts still regarded the predictions of IPCC AR4 as about right. Who are these experts?

2. An emergency stop

Unpleasant surprises with regard to climate change are happening with increased frequency. The current warming of the Arctic regions is worrying, especially the distance to which this warming penetrates into Siberia, which contains large amounts biomass that can release carbon dioxide and methane. There are reports of increased methane from biogenic sources from this region. This is one of several possible feedbacks that might contribute to dangerous climate change. Some scientists fear that shallow water clatherates may be triggered. It is possible that short term dangers are much greater than expected.

Question 2.1 :

Will the CCC look for contingency policies which might effect an "emergency stop" to climate change?

3. Emissions of greenhouse gases for the UK?

Government sources estimate that the average UK citizen is responsible for approximately 11 tonnes of greenhouse gases, measured as carbon dioxide equivalent(CO2e). This excludes international air travel, international shipping and the emissions of greenhouse gases generated when goods are manufactured overseas which are subsequently imported into the UK.

Mike Berners-Lee, of Small World Consulting Ltd has used input-output analysis to make estimates of the missing elements. He says of his, yet unpublished, work

The UK's imports account for a very significant proportion of its greenhouse gas footprint. Input-output analysis is a useful tool for estimating this, although it is very difficult make accurate assessments. Our modeling indicates that when the relative greenhouse gas efficiency of overseas industries is taken into account, (along with international transport and an appropriate treatment of radiating forcing from high altitude emissions) the UK's imports account for 30 to 50% of its greenhouse gas footprint.

This would put emissions at about 20 tonnes CO2e for each UK citizen.


3.1 Does the CCC think this is near the correct figure, when these extra sources are included?

4. Should the bystander effect inhibit climate change education?

The "bystander effect" occurs when people are confronted by issues of great consequence, conclude the issue is too big to tackle and believe that any efforts they make will make little difference. They become bystanders rather than participants. Policy makers often use this effect as a reason for downplaying any indications that climate change may be worse than official science predicts.

Policy options range between downplaying the seriousness of climate change, because of bystander effects and publicising the facts with aggressive advertising and educational campaigns. The relevance of different policy options depends on the target group.


4.1 What educational policies does the CCC think are relevant for these groups: the public, local

councillors, MPs, government ministers, departmental officials &Etc. In particular, does the CCC believe it has a role in formulating a policy to educate MPs?

5.New Building

Government policies are aimed at reducing energy use and in buildings and consequently reducing greenhouse gas emissions. The Passive Haus standard from Germany can cut the use of energy by 90% and the government is setting standards for new building that they call "zero carbon homes".

A problem with zero carbon homes is that government policy does not require any estimate of the greenhouse gas emissions created as a result of the construction process.

This is a serious omission. For example, the Peabody trust says of the Beddington Zero Energy Development "BedZED is therefore a carbon neutral development - resulting in no net addition of carbon dioxide to the atmosphere". But a report by Bioregional gives a figure of 675 kilograms of carbon dioxide for every square metre of floor space. The embodied carbon dioxide of a three bedroomed flat is given as 67.5 tonnes. If a personal carbon budget were to be 2 tonnes CO2e per year and a quarter was allocated to the "home budget", this would take 270 years of a personal budget.

It is possible to build dwellings that incorporate materials that have captured carbon from the atmosphere, making them store of carbon.


5.1 Will the CCC investigate whether the greenhouse gases emitted as a result of building construction should be estimated in the planning process?

5.2 Tall buildings create more greenhouse gases per square metre of floor area than low buildings. Will the CCC ask for this to be taken into account in government planning policy?

6. Ecotowns

Ecotowns are towns that have a privileged position in the planning system. They are intended to cut greenhouse gas emissions. But it is not clear that there are mechanisms which make residents of ecotowns have lifestyles that are significantly lower in carbon.

Given the location of proposed ecotowns, the suspicion must be that the new residents will come from demographic groups that naturally have high footprints. The P2 People and Places demographic system identifies that most of the ecotowns on the shortlist (but not Rossington) as typical places for demographic groups B4 (Rural Comfort) and C3 (Thriving Families). These groups are more likely to be frequent fliers and heavy users of transport fuel.

It would be possible to modify the behaviour of residents of ecotowns by a range of legal and financial measures which wold have the effect similar to a local personal carbon ration. With the additional help of good planning, it could be possible to integrate schools with local catchments, have shops which have carbon friendly pricing policies and incorporate local food production. But for such possibilities to be fully effective, ecotowns, with a typical size of 10,000 dwellings, are too small. They should be ecocities, with typical sizes ranging from 100,000 to 1 million dwellings.(See


6.1 Can the CCC make recommendations on planning policy?

6.2 Will the CCC consider whether ecotowns could have a local personal carbon rationing or trading schemes?

6.3 Will the CCC consider changes in legislation to enable local legal and financial frameworks aimed at combating climate change?

6.4 Will the CCC consider asking DCLG to consider the matter of greenhouse gases created as a result of building construction when considering ecotowns?

7. Access to information

Information on climate change is often difficult to access - there are often financial and legal barriers. There are several possible reasons for this.

The structure of the "climate change research industry" is a problem. Information can be protected by copyright or obfuscation or may simply be hidden. It is in the interest of researchers, academics and consultants to protect their information so it fetches a higher price. Restricting access to information can also be in the interests of government departments which do have other policy objectives.


7.1 Will the CCC investigate access to climate change information and whether the government should make more information freely and easily available?

Little work appears to have been done on the effect that timing of greenhouse gas emissions has on longer term climate change. Timing of investments and expenditure have a considerable weight of theory in economics. The concept of discount rate is useful in comparing present expenditure with future expenditure. Such concepts could be used to explain the time dependence of anthropogenic climate forcings in a way accessible to economists.


8.1 Can the CCC answer questions such as: If one gigatonne of CO2 is released into the atmosphere this year, how much must be removed in twenty years time to bring the climate back to the state it would been in had the release never happened. To what extent do positive climate feedbacks affect this question?

8.2 Will the CCC consider the costs associated with "reseting the climate"? E.g. Will sequestration become less expensive and will it balance the extra CO2 to be withdrawn as a result of positive climate feedbacks?

Affluent lifestyles have greater impacts on the climate than less affluent lifestyles. I have performed some estimates of carbon footprints ( as CO2 equivalent per year) using the P2 People and Places geodemographic classification from Beacon Dodsworth. In conjunction with the results of the Target Group Index from the British Market Research Bureau, I used selected P2 branches to get the following

P2 branch Private transport CO2e per year Air travel CO2e per year
A1 - Worldly Horizons 4.0 tonnes CO2e per year 0.78 tonnes CO2e per year
A5 - Established Prosperity 3.5 tonnes CO2e per year 0.76 tonnes CO2e per year
D11 - Matrimonial Homes 3.4 tonnes CO2e per year 0.48 tonnes CO2e per year
G17 - Aspiring Streets 3.7 tonnes CO2e per year 0.49 tonnes CO2e per year
M35 - Impoverished Elders 2.6 tonnes CO2e per year 0.37 tonnes CO2e per year
L37 - Deprived Youth 1.8 tonnes CO2e per year 0.21 tonnes CO2e per year

The P2 classification is ranked in terms of affluence.


9.1 Will the CCC be using any geodemographic classifications to understand the impact of different lifestyles on climate change?

9.2 The principle of Contraction and Convergence is usually applied to nations. It demands that developed nations reduce their greenhouse gas emissions by a greater proportion than developing nations. Will the CCC consider C&C in relation to demographic classes?

10. Biochar

Biochar is considered to be one of the most promising methods for sequestering carbon. However, knowledge about the possibilities of biochar is not widespread.


10.1 What knowledge does the CCC have about biochar?

10.2 Will representatives of the CCC be visiting the International Conference on Biochar in September? (2008 Conference of the International Biochar Initiative, Newcastle, United Kingdom, September 8 – 10, 2008. )

Concerns have been raised that a large proportion of aid to developing countries is wasted by poor governance.


11.1 Will the CCC be considering a role for payments for carbon sequestration as an addition or a replacement for development aid?

11.2 Specifically will the CCC consider the possibility payments to build up soil carbon with biochar?

Backfire effects occur when a policy produces unintended results that work in the opposite direction to desired policy goals. For example, if houses were better insulated, as a matter of energy-saving policy, occupants may choose to increase the temperature of their houses. This would detract from the energy saving policy.


12.1 Will the CCC be doing any work on this backfire effects?

One concern underlying question 1 was that methane from the Siberian tundra had not been incorporated in the Hadley Centre's Earth Systems models. These models were an important feature of IPCC AR4. I now have a communication from Professor Wadhams indicating that clatherates are releasing methane from the sea off Eastern Siberia. He says:

" I have been very slow in answering your message! My excuse is that I was away in the Arctic. The US study of accelerated warming within 1000 miles of the coastline of an Arctic Ocean where the sea ice is retreating is, I think, a sound piece of science. It is very worrying because here we seem to have a multiple positive feedback: global warming causes sea ice to retreat; retreating sea ice enhances the warming rate on land in the Arctic; this causes permafrost to melt more rapidly; this releases methane which is a powerful greenhouse gas. Already there is a paper in press by a group at University of Alaska which has measured plumes of methane rising from melted underwater permafrost in the East Siberian Sea, so the process of methane release is already under way.

This and many other factors seems to always come down to the same thing: change is happening faster than our predictions, because our predictions are based on imperfect knowledge of the physics and chemistry, and we unfortunately find that increasing knowledge is always leading to the discovery of new positive feedback loops rather than negative ones.

My fear is that we have already gone too far. Unthinkingly we have put so much CO2 into the atmosphere that it has initiated a rapidly accelerating warming which will go on now whatever we do to cut down our emissions, because of the persistence time of decades that CO2 has in the earth system. This doesn't look good, and the fact that in reality, for all the talk, no serious concrete action has been taken by anyone to cut down on CO2 emissions, leaves me feeling very pessimistic about the future of our planet. "

QUESTION 13: Is Professor Wadhams correct?
Is it too late to stop dangerous climate change?

Geoff Beacon

Beacon Dodsworth Limited

August 2008

The following is the anwers I received from Enquiries(CCC) in October 2009

  Dear Mr Beacon

Thank you for your email and your patience in waiting for the answers.

As the questions relate to Lord Turner’s appearance of 2nd July 2008, most of the questions 
will have already been covered by our advice to Parliament contained in our reports from 
December 2008 available >here< and the recently published step change report available >here<.

Q1.1: Our 2008 report did indeed emphasise that observed decreases in Arctic summer sea ice 
      during 2007 and 2008 have been at the very top end of what climate models have suggested. 
      It is important to note however that sea ice, along with many other aspects of the climate 
      system, shows year-on-year variability due to chaotic weather patterns. As yet it is still 
      unclear to what extent this decrease is the start of a more rapid decline, and how much is 
      a short-term result of natural variability from which there will be some recovery (although 
      this would clearly still be part of a longer-term declining trend). More information can be 
      found here: In general, periods 
      of at least 30 years are used to identify climate trends, in order to filter out the 
      influence of natural variability.

      The accuracy and reliability of climate models and their predictions are tested using a 
      large number of real-world observations or ‘milestones’. These include ability to reproduce 
      observed trends in seasonal surface temperatures, precipitation and sea level pressure, as 
      well as natural patterns such as El Nino. More information is available in the IPCC Working 
      Group 1 4th Assessment (AR4) Chapter 8, here:

Q1.2: There are a number of world-leading models which are used in assessments of climate, and 
      the research teams behind each of them continue to work on improvements. Whilst a list of 
      models participating in IPCC AR4 can be found at, 
      the CCC is not in direct communication with all of them. We recommend that you contact 
      these groups directly to find out about their latest improvements.

Q2.1: The CCC recognises that there is uncertainty in various parameters of the climate system 
      that are important for projecting future climate change. As a result we took a risk-based 
      approach to setting targets in the 2008 report. Climate modelling work carried out by the 
      Met Office identified probabilistic ranges of warming for different future emissions 
      pathways. These ranges reflect the fact that some processes (for instance carbon cycle 
      feedbacks or climate sensitivity) could be stronger than simply the ‘best guess’ or 
      ‘central estimate’ values in the literature (see the Technical Appendix to Chapter 1,%20concentrations%20and%20temperatures.pdf 
      for more details). The CCC’s recommended emission targets were based on an emission 
      trajectory which gives a 50/50 probability of staying close to 2 degrees this century, 
      whilst also minimising the probability of an extremely dangerous 4 degrees increase, 
      based on the best current information.

      Beyond accounting for the possibility of stronger feedbacks in this way, it is unclear 
      what you mean by an ‘emergency stop’. Where there any particular suggestions you had 
      in mind?

Q3.1: The CCC is unable to comment on unpublished work. The UK carbon budgets are on a 
      ‘production’ basis, i.e. they refer to gases emitted directly by the UK net of any carbon 
      credit trading. UK emissions on this basis were slightly under 11MtCO2e per capita in 2006 
      excluding international aviation and shipping (IAS), and slightly over 11MtCO2e including 
      IAS on a bunker fuels basis. We have not attempted to measure the UK’s emissions on a 
      ‘consumption’ basis.

Q4.1: Policy options are for the relevant Government departments. The CCC reports to Parliament 
      and has given its evidence to various Parliamentary Committees.

Our advice to date has not covered educational policies. The Committee’s role is set out in the 
      Climate Change Act (2008), and our advice under that remit is given directly to Parliament 
      as a published document.

5.1 Will the CCC investigate whether the greenhouse gases emitted as a result of building 
    construction should be estimated in the planning process? Ute

    To date, the CCC has focused its analysis on emissions from existing buildings as new built 
    emissions account for a very small percentage of the total in the first three budget periods. 
    As we look at future budget periods, we will consider the role of new built, including the 
    issue of life-cycle emissions.

Q5.2: Tall buildings create more greenhouse gases per square metre of floor area than low 
      buildings. Will the CCC ask for this to be taken into account in government planning 
      policy? Ute

      This is not something we have considered as we have done very little analysis on 
      new-built to date.

Q6.1: Yes we can, in areas where planning policy has an impact on carbon budgets. We consider 
      various planning policy measures in the transport chapter of our October 09 progress report.

Q6.2: We have not considered the issue of personal carbon rationing and currently have no plans 
      to do so.

Q6.3: The CCC is an advisory body; changes to legislation can only be done by Parliament.

Q6.4: If our future analysis on new built housing shows that this is an important issue, we will 
      consider it.

Q7.1: It is not in the remit of the CCC to investigate access to information. You may wish to 
      look at the website of the information commissioner. 

Q8.1: There is recent research (two papers on this subject are here and here suggesting that the specific 
      timing of CO2 emissions is less important than the overall total amount of CO2 that is 
      emitted over time. Including the effect of carbon cycle feedbacks in the climate system, 
      these studies imply that a gigatonne of CO2 emitted in 20 years’ time would have the same 
      result (in terms of temperature increase) as a gigatonne emitted now.

Q8.2: We have not yet set our work plans for our future progress and budget reports. We will 
      consider those issues relevant to providing our advice as required under the Climate Change 
      Act and requests made under the powers of the Act.

Q9.1: We have not yet set our work plans for our future progress and budget reports.

Q9.2: The CCC’s ‘Building a Low Carbon Economy’ Report deals with burden-sharing methodologies 
      in chapter 1.

Q10.1: We have not covered this issue explicitly in our reporting to date.

Q10.2: This event took place before the questions were sent.

Q11.1 & Q11.2: Development aid is not covered in the Climate Change act.

Q12.1:  There is no plans for any specific work to be undertaken in relation to the theory of 
        backfire or rebound effects in respect of household energy efficiency.  However this is 
        an area that the CCC is aware of.

Q13:  You are correct that natural release of methane as temperatures rise is an issue of concern, 
      and is one that we highlighted specifically in Chapter 1 of our 2008 report. Recent estimates 
      suggest that it will cause additional local warming, perhaps similar to the level brought 
      about by methane emissions from human activities 
      (see, but there is no science to 
      our knowledge which implies this will cause a ‘runaway’ feedback from which temperatures 
      never stabilise. The CCC relies on peer reviewed publications in its analysis, and is keeping 
      a close eye on emerging findings about natural methane release.

      In terms of ‘dangerous’ climate change, two degrees is widely adopted as the threshold after 
      which dangerous climate change occurs. This is of course a value judgment, based on the 
      scientific evidence. As explained above the CCC took a risk-based approach to setting a 
      climate target which reflects the importance of two degrees and also the scientific 
      uncertainty in projecting future climate. Scientific consensus is that it will be possible 
      to avoid this level of climate change, if the world acts quickly to curb emissions. The 
      emissions targets recommended by the CCC are designed to ensure that the UK fully plays its 
      part in meeting the challenge.

I replied on the 2nd November 2009


Thank you for your reply. Although this is over a year since I originally asked the questions, 
I feel that your answers, though limited by your constitutional postion, are knowledgeable 
and seriously meant. I will make a few preliminary comments:

You say:

"Q8.1: There is recent research (two papers on this subject are here and 
suggesting that the specific timing of CO2 emissions is less 
important than the overall total amount of CO2 that is emitted 
over time. Including the effect of carbon cycle feedbacks in the 
climate system, these studies imply that a gigatonne of CO2 emitted 
in 20 years time would have the same result (in terms of temperature 
increase) as a gigatonne emitted now."

I am aware, in general terms, of these arguments. In "normal" circumtances, carbon dioxide 
stays in the atmosphere a long time. What is curently emitted may be large but will not 
increase the concentration in the atmosphere by large percentage. But this does not 
account for the danger of a climate "tipping point" being reached. The research you 
report - that specific timing of CO2 emissions is less important than the overall total 
amount of CO2 that is emitted over time - assumes that no climate tipping points are near. 
If such possibilities are serious we may consider we taking risks all the time CO2 
has an atmospheric concentration greater than 350 ppm. Have you any evidence which excludes 
these possibilities? 

Put another way "How low are the probabilities you assign to climate feedbacks such as 
large releases of methane from shallow sea in the Arctic or the Amazon rainforest drying?

Please comment on the following:

It's methane that worries me - it's a strong greenhouse gas and a big danger. It probably 
caused mass extinctions in the past.

There's lots of methane under oceans - some in seas near the North Pole. This is beginning 
to bubble up as the Arctic warms. 

The warming also uncovers ancient plant matter that rots to produce methane and carbon dioxide.

Scientists can't estimate how big these effects will be - they have only just started. Some 
say they are worried, some say very worried. 

But methane could be an opportunity. It is cleared from the atmosphere in about 12 years so 
stopping new emissions would reduce the pace of global warming quickly. The big human sources 
are coalmining, paddy fields, grass burning and livestock.

A recent report by World Bank staff says livestock is half of man-made global warming. Defra 
funded research shows that beef and lamb are particularly bad. 

I feel we in the UK should create environmentally friendly lifestyles that the rest of the 
world would be eager to follow. Look at to see an example of the 
approch I currently favour.

I will contact you later about an "emergency stop". 

Geoff Beacon

I received the following reply on the 2nd Novamber 2009


Thank you for your email. On the subject of methane and climate feedback; we do not assign 
probabilities to methane release because we do not yet know enough about these processes 
to include them in our models projections. We do however draw attention to this in our 
'Building a Low Carbon Economy' Report - December 2008.

We do discuss the opportunities to reduce UK methane emissions in chapter 9 of the same report.

Kind regards


If I had had the energy, I would have argued that methane wasn't the only worrying feedback.
I did receive a very helpful email from John Mitchell, Principal Research Fellow at the Met
Office in March 2012, which confirmed my worries.

  Hi Geoff
I apologise for not answering earlier - I now work part time.
Based on help from my colleagues
          1.  reduced sea ice cover reflecting less of the sun's heat back out to space,

          2.  changing ocean circulation patterns
1,2 are in most models and have been for years 

          3.  less carbon dioxide absorption by the oceans

          4.  increased soil respiration

3,4 are in most carbon cycle models and fairly well established. There are a good number 
of such models in the current IPCC assessment

          5.  more forest fires
5 we don't do yet, but could be important for changing ecosystems response to climate. 


          6.  melting permafrost emissions (6a CO2, 6b CH4)
6a/b we don't have in the GCM, but have some simple modelling of. Too early to show any 
results yet, but we plan to publish later this year. Bottom line is that both CH4 and 
CO2 will be released as permafrost thaws. The magnitude is uncertain, but likely to be 


          7.  increased decomposition of wetlands
7,  we have in HadGEM2 but didn't enable as a fully coupled feedback, but we can diagnose 
changes in wetland extent and CH4 emissions

I would add that although these things may be important, they are not always easy to quantify, 
model, initialize  and validate, especially 5-7. That is why is taking time ot implement them.