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Discussion: (8 comments)

  1. Benjamin Cole

    I don’t care much about CO2 as the evidence it does much is weak…that said, capitalism is not the answer to the pollution problem…as every classic economist knows, the price signal does not capture the cost of pollution…he who excretes at least cost (to himself) wins…there is also the problem of property rights…does anyone have the right to pollute your land and water? The air you necessarily breathe? Are those Constitutional rights?
    It is dunce-work to suggest pollution neither needs taxing or regulation…

    1. I don’t care much about CO2 as the evidence it does much is weak…

      The evidence is not weak. It is certain. All plant growth depends on CO2 and most plant growth is limited by the atmospheric concentration of CO2.

      To assimilate CO2 plants must have a path for gaseous diffusion between the photosynthetic tissue and the atmosphere. But that path not only allows inward diffusion of carbon dioxide, it allows outward diffusion of water vapor. Thus, a doubling atmospheric carbon dioxide concentration doubles the rate at which plants exchange water for carbon dioxide, which in turn has the potential to double the rate of plant growth in water limited environments.

      So carbon dioxide does much, and while some of what it does may be judged beneficial (e.g., increased dry land crop yields, and thus likely global population) it will play havoc with the structure of many ecosystems, with end results that are incalculable.

      But, yes, to limit pollution the most efficient solution is to tax it, or so argues economist and climate change skeptic Ross McKitrick.

      1. CS

        Thus, a doubling atmospheric carbon dioxide concentration doubles the rate at which plants exchange water for carbon dioxide…

        That’s not exactly correct, but nonetheless your conclusion is correct.

        Plants don’t just exchange water for CO2 at a fixed rate. Your description of gaseous diffusion between the photosynthetic layer and the atmosphere is correct, but since plants can control the size of the stomata on leaves through which this diffusion occurs, at higher CO2 concentrations it’s possible to reduce the amount of water lost proportional to the amount of CO2 absorbed, so it’s not correct to say that doubling the CO2 concentration allows a doubling of the exchange rate. If that were true, a doubling of CO2 would require a doubling of water used also.

        [increased CO2] “…it will play havoc with the structure of many ecosystems, with end results that are incalculable.

        Oh dear! How awful! What could those results possibly be?

        But, yes, to limit pollution the most efficient solution is to tax it, or so argues economist and climate change skeptic Ross McKitrick.

        Yes, of course. As with anything else, taxing something means you will get less of it.

        McKitrick’s suggested policy is to impose a revenue neutral tax on carbon dioxide emissions and reduce other taxes with the tax revenue generated. Assuming that is, that increased atmospheric CO2 levels are, in fact, harmful, and that increased atmospheric CO2 levels are mostly anthropogenic. Both of those are really big ifs.

        It’s correct to describe McKitrick as a global warming skeptic. He has written, with co-author Steve McIntyre, a searing indictment of the inadequacy and outright fraud of Michael Mann’s Hockey Team and their signature “hockey stick” graph which purports to represents historical temperatures.

        He has also written an excellent book on the subject of climate science, “Taken by Storm” with co-author Chris Essex.

        1. it’s not correct to say that doubling the CO2 concentration allows a doubling of the exchange rate

          Of course it’s correct. Except it does not “allow” a doubling, it just doubles it! The rate of exchange depends solely on the concentration gradients of water vapor from intercellular tissue spaces to the atmosphere and of CO2 from the atmosphere to intercellular tissue spaces.

          If that were true, a doubling of CO2 would require a doubling of water used also.

          Rubbish. All other things being equal, a doubling of atmospheric CO2 concentration allows, but does not necessitate, a doubling of plant carbon assimilation without any increase in water use. More usually it results in some increase in carbon assimilation with some reduction in water use. But rapid adaptive evolution can occur resulting in fuller use of available water in an increased CO2 environment.

          1. CS

            That’s better. Your fuller description explains the exchange correctly. Your original statement is ambiguous, and open to misinterpretation.

  2. Mr. Econotarian

    Other sources suggest “Climate change may have helped reduce carbon emissions: About half of the overall decline in energy consumption came in the residential sector. And some of that decline was due to an incredibly warm winter in 2012, which led to a 22% reduction in cumulative heating degree days compared with 2011.”

    Also influencing energy intensity of the US economy was that “industrial output was 2.7% lower in 2012 than in 2007, and manufacturing output was 5% lower in 2012 than in 2007.”

    http://nation.time.com/2013/10/22/efficiency-natural-gas-keep-pushing-u-s-carbon-emissions-down/

    Although I’m sure replacement of coal with fracked gas was important as well.

    1. manufacturing output was 5% lower in 2012 than in 2007

      And insofar as that output was off-shored, the reduction in US carbon emissions will have been balanced by similar emissions by off-shore producers, resulting in the same global environmental impact as if the emissions originated in the US.

      1. Glad you’ve got it now.

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