04 October 2009

Unpublished Letter to the FT

Chris Green and I sent this in one week ago, in response to a letter from Lord Nicholas Stern. It was not published so we are sharing it here.

In his letter to the FT of Septermber 25, 2009 Lord Nicholas Stern asserts that current goals for emissions reductions in the context of modest economic growth imply a need to cut emissions per unit of GDP by at least 75% across the US, EU, Japan, Indonesia, Brazil, and China. However, he is a bit too glib when he claims that the current pace of technological progress, efficiency gain potential and deforestation "make it clear" that such a goal can be achieved in the next 20 years. First, while deforestation may indeed play a role in taking up excess carbon dioxide, it is unrelated to the decarbonization of the global economy and should not be included as a strategy toward that end. Second, Stern's 75% improvement in carbon intensity across these countries implies a 6.9% annual rate of decarbonization, which is about 4 to 5 times faster than historically has occurred and higher even than the highest sustained rate of decarbonization ever achieved in a large economy. The technologies needed to accelerate decarbonization are not yet ready at scale, and there may be limits to how fast and how far efficiency gains can take us. Further, we are taking on this challenge from, at best, a "standing start" as rates of decarbonization have slowed in many countries in the current decade.

The pace at which policy makers are stepping back from grandiose expectations for the upcoming Copenhagen climate meeting should tell us that the scale of the challenge is at least implicitly understood by those who would be faced with meeting goals that no one currently knows how to meet. Consequently, overly optimistic and misleading claims of the achievability of the rate of decarbonization suggested by Lord Stern, and others, only delay the time until we can adopt an approach to climate policy grounded in realism rather than exhortation.

Roger Pielke Jr., Professor
University of Colorado

Christopher Green, Professor
McGill University


  1. minor point of etiquette: he was "Sir Nicholas", he's now "Lord Stern"...

  2. Isn't this (with Rajendra Pachauri's statement) a standard fear driven negotiating ploy ?

    The management announces that 50% of employees will be made redundant and those left will have to work twice as hard for the same pay. Two weeks later an agreement for 25% redundancies and a 2% pay increase for those remaining is negotiated and everybody is happy because 'it could have been a lot worse'. Works every time.

    Some of us wonder why a privately funded British economist is negotiating with the whole world over its fundamental future development. He produced a report for the government but he is paid by Jeremy Grantham.

    This is Christopher Brooker in the Telegraph (Monday) elucidating how the British Met Office (Hadley Centre) became an instrument of British government policy starting with Margaret Thatcher.


    My own website has more detailed links including British government propaganda campaigns and the fact that Deputy Prime Minister John Prescott single handedly pushed through the Kyoto Protocol (from the Guardian).


  3. You meant reforestation rather than deforestation didn't you? Stiglitz has a new group that proposes that reducing deforestation should be the main plank of decarbonization so maybe that's where Stern is coming from. Oddly though everyone seems to be of the impression that deforestation is actually growing out of control but the actual satellite data says the opposite - ie that the planet has been healthily greening for 25 years. Of course if their models say different then that's what they believe. Yet more policy based on fundamentally poor research! Still focusing on the trees is a lot easier than magicking up a green fuel source so I can understand. Most modern economists are totally discredited by now and the numbers are all pure guesswork anyway so who's listening? It's in the nature of economists to be optimistic though - just as much as it's in the nature of earth scientists to be pessimistic.

  4. -3-jgdes

    Actually should be "reduced deforestation"



  5. Roger:

    Your: "First, while (reduced) deforestation may indeed play a role in taking up excess carbon dioxide, it is unrelated to the decarbonization of the global economy and should not be included as a strategy toward that end" is basically in error.

    Better managing of forests provides the most practical way to begin to 'immediately' reduce atmospheric CO2 and buy enough time to permit energy conservation and the development and testing of new technology to begin to make more of a difference.

    That is the message of my:

    "Replacing coal with wood: sustainable, eco-neutral, conservation harvest of natural tree-fall in old-growth forests"


    Abstract: When a tree falls in a tropical old-growth forest, the above ground biomass decays fairly rapidly and its carbon is returned to the atmosphere as CO2. If the trunk of that tree were to be harvested, before decay, and were stored anoxically, or burned in place of coal, a net of about 2/3 of that amount of CO2 would be prevented from entering the atmosphere. If the ash-equivalent of each tree trunk (about 1% of dry mass) were recycled to the site of harvest, the process would be indefinitely sustainable and eco-neutral. Such harvest of the undisturbed old-growth forests of Amazonia and Equatorial Africa could effectively remove about 0.88 to 1.54 GtC/yr from the atmosphere. With care, additional harvest of adjacent live trees, equaling up to two times the mass of the fallen trees, might be similarly collected, just as sustainably, and with almost as little ecological impact. This very large contribution to the mitigation of global warming is discussed – with caveats. It could result in substantially reduced coal emissions, but without closing down many presently coal-fired power plants – and at much lower cost and lead-time than carbon capture and sequestration (CCS).

    that I posted in your "Environmental Perversity" thread – but to which you have so far not responded.

    Using wood in place of coal – and at the same time, preventing further deforestation – are intimately tied together. And since deforestation is responsible for the release of about 1 - 2 GtC/yr, it has a large effect on how practical any proposed targets and menu for conservation might be.

    At least Stern recognizes the latter important connection.

  6. -5-Len

    At the risk of getting into a semantic debate I believe that what you are talking about is "enhanced sequestration" which is not the same as "avoided deforestation".

    I am already on record as supporting research into direct air capture, and biological means of air capture are a part of that.

  7. Roger:

    Of course "enhanced sequestration" is entirely different from "avoided deforestation"! This is not a semantic problem.

    The decisions that must be made to accomplish enhanced sequestration often are just those that are also likely to encourage MORE destructive deforestation by 'other actors' – as discussed in my "Substituting Wood for Coal..." paper. So the issues of "decarbonization of the global economy" can be INTIMATELY INVOLVED WITH issues of "avoided deforestation" and therefore require very careful policy formulation and execution!

  8. Burning wood directly is problematic because of the high water content in fresh wood. That isn't a problem if you put the wood in a gasifier to produce CO and H2. That can be burned in a power plant directly or used to produce methanol or a long list of other chemicals including gasoline and diesel fuel. There are varieties of trees that produce as much or more cellulose per acre as the highly touted grasses. The high bulk density of wood means that it's easier to transport than grass. Gasification means you don't have to separate the lignin and hemicelluloses, which has to be done before enzymatic conversion of cellulose to sugars. Gasification is known technology. Eastman Chemical has been gasifying coal to produce acetic anhydride for over twenty years.

  9. DeWitt:

    You're properly addressing details that become important when bio-fuels seriously begin to compete with fossil fuels – for example, when 'effective taxes' on fossil fuels seem to make wood and corn ethanol attractive alternates. It's THEN that market pressures to harvest bio-fuels will become overwhelming and will exert enormous pressures to INCREASE deforestation.

    Most people (apparently Roger and certainly Jim Hansen) still don't make this connection. This is why Stern is right to intimately connect deforestation with "decarbonization".

    And this is why EXCEPT for bio-harvest that results in ZERO or NEGATIVE CO2 footprint (as carefully defined in my paper) such harvest must be subject to 'an effective carbon tax' in proportion to its POSITIVE CO2 footprint – just as has been proposed for fossil fuels – otherwise catastrophic deforestation will proceed with a vengeance!