Peak oil may solve climate change

Congress has recently passed legislation that would cap carbon emissions. The Administration strongly supports such controls. The EPA finds that CO2 endangers public health and welfare. Many studies postulate severe global consequences if CO2 concentrations are not constrained.

Most climate change models assume that future CO2 emissions will grow exponentially over this century. Intuitively, anyone who recognises the practical limitations on fossil energy supply knows emissions will not rise exponentially for another century, as portrayed by the IPCC and the US Global Climate Change Research Program (Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson).

The exponent - about 1.4 per cent per year - on average, is not very large, but compounded over the next century it would suggest that by 2100 we would be consuming more than three times more fossil energy than we consume today. In the meantime, according to these figures, we will have consumed about 15 trillion barrels-of-oil-equivalent (boe).

Fifteen trillion boe is an astounding number considering we only have about 13 trillion boe on earth in oil, gas, coal, oil sands, heavy oil and oil shale combined. And only a portion of this total, probably no more than one-third, can ultimately be recovered under reasonable economic conditions. This disparity, between IPCC projections and fossil fuel reality, is sufficient to call into question all the conclusions of the climate change models, as future CO2 concentrations are the principal input to the model that drives all the outputs.

The fact is, oil is peaking about now, gas will probably peak within a decade, and coal within a couple of decades. Unconventionals like oil sands and oil shale will likely make up only a few million barrels per day when global energy peaks. Unconventionals can take away some of the pain on the tail, but realistically these resources can’t do much to change the timing of the peak.

Unrealistic expectations of fossil energy supply is but one glaring error in the climate change science. A second is the systematic underreporting of the beneficial impact higher CO2 concentrations have on photosynthesis. It has been known for decades that there is a large difference between what we emit and what shows up in the atmosphere (compare emissions compiled here with atmospheric CO2 concentrations here). This “missing carbon” - which ends up in the ocean and plants - has been growing. Forty years ago humans emitted about 13.6 billion tonnes of CO2, of which about 5.5 billion tonnes went “missing”. In 2008 we emitted about 34.2 billion tonnes, of which 18.8 billion went “missing”. A prime suspect for this missing mass is the fertilisation effect that CO2 has on photosynthesis rates.

The “missing mass” is growing at its own exponential pace. In this case the exponent for the CO2 concentration effect on “missing mass” is about 1.2 (using pre-industrial concentrations of 280 ppmv as the baseline) and compounded growth rates are about 0.5 per cent. The fact that the reaction order is higher than first order strongly implies that biokinetics dominates the mechanism.

Summing all the years of biosequestration we conclude there is 23 per cent more living mass on earth today than there was 40 years ago. This is a natural, global effect: improvements in domestic agricultural technology can only account for a small fraction of this increased plant growth.

For projecting future atmospheric CO2 concentrations, we used this biokinetic model to compute the rate of biosequestration on removing CO2 from the atmosphere. For estimating oil and gas emissions we used Campbell’s ASPO curve (PDF 251KB) and for coal emissions we used the Energy Watch Group 2007 Coal Report (PDF 534KB). Combining peak fossil energy production with the exponential growth in biomass due to increased CO2 concentrations we arrive at the curve shown below.

The resulting curve shows that peak fossil energy will soon begin to limit emissions, and that the maximum CO2 concentrations of about 412 ppmv, occurring about 25 years from now, will be far below the threshold of 450 ppmv cited by climate change experts as the upper acceptable limit (Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson). Further, the graph shows how the slope of the IPCC curve does not agree, even at present, with the slope of the observed curve; a consequence of IPPC’s failure to recognise the magnitude of the biokinetic rate and reaction order.

From this exercise we conclude that geologic and economic limitations to global fossil energy production will naturally limit the extent of future climate change, but without the bureaucracy and economic distortions that will result from Cap and Trade. Looking at the overall impact on life, and the continuing growth in World population, we may come to appreciate the positive effects that higher CO2 concentrations have on our food supply. Spending wealth to reverse this benefit may prove to be exactly the wrong thing to do.

Imposing regulations on carbon emissions will only exacerbate what will already be a painful adjustment to supply limitations. It will almost certainly distort what otherwise would be more thermodynamically efficient pathways to growing economies. Rather than making the problem worse through regulation, political efforts would be better spent on improving efficiency of energy use, and helping to ensure we have adequate domestic supply of fuels when the world-wide competition for dwindling supply begins in earnest. That time is not long from now.