By James W. Bunger, Ph.D.
Although the Intergovernmental Panel on Climate Change takes a very bullish view of global fossil fuel reserves and resources, climate scientist Jim Hansen and Cal Tech’s David Rutledge have demonstrated that peaks in oil, gas, and/or coal production might help limit future global warming. This week’s commentary examines whether the effect of such peaks combined with an increase in natural sequestration might obviate the need for climate policy. The notion that climate change could be self limiting is highly controversial, and deserves further study. The views expressed here are those of the author, not ASPO-USA.
The House of Representatives recently passed legislation that would cap carbon emissions. The Administration strongly supports such controls. The EPA has ruled 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 recognizes 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 (ref-1). The forecast growth rate in energy consumption-1.4% per year-is not very large, but compounded over a century it would suggest that by 2100 we would be consuming three times more energy than we consume today. In the meantime, we will have consumed about 15 trillion barrels-of-oil-equivalent.
That is an astounding number considering we only have about 13 trillion barrels-equivalent in oil, gas, coal, oil sands, heavy oil and oil shale combined. And only a portion of this total, perhaps 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 the conclusions of the climate change models, as future CO2 concentrations are the principle 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. Unconventional tar 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 future fossil energy supply are 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 in ref-2 with atmospheric CO2 concentrations in ref-3). This ‘missing carbon’-which ends up in oceans and plants-has been growing. Forty years ago humans emitted about 13.6 billion tonnes of CO2, of which about 5.5 billion tonne went ‘missing’. In 2008 we emitted about 34.2 billion tonne, of which 18.8 billion went ‘missing’. A prime suspect for this missing mass is the fertilization 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 1.01 percent (using pre-industrial concentrations of 280 ppmv as the baseline). The fact that that the reaction order is higher than first order (1) strongly implies that biokinetics dominants the mechanism.
Summing all the years of biosequestration we conclude there is 23% more living mass on earth today than there was 40 years ago. Because this is a global effect that is dominated by natural vegetation and the oceans, domestic agricultural technology can only account for a small fraction of this increased plant growth; the balance is a natural response. As an aside, we may come to appreciate the positive effects that higher CO2 concentrations have on our food supply.
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 (ref-4) and for coal emissions we used the Energy Watch Group 2007 Coal Report (ref-5). 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 (ref 1). 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 recognize the magnitude of the biokinetic rate and reaction order. From this exercise we conclude that, because it is global in scope, geologic and economic limitations to fossil energy production may naturally limit the extend of future climate change, but without the bureaucracy and economic distortions that will result from a cap-and-trade scheme.
Imposing regulations on carbon emissions will only exacerbate what will already be a painful adjustment to supply limitations. Rather than making the problem worse through regulation, political effort should 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.
James Bunger holds a Ph.D. in Fuels Engineering, and has served on the research faculty of the University of Utah, State Science Advisor for Utah and Chairman of the Petroleum Division of the American Chemical Society. He consults in the field of unconventional oil resources. firstname.lastname@example.org
- Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, (eds.). Cambridge University Press, 2009. (use orange line from graph on page 23 and reference to 450 ppmv threshold on pages 23 and 24.)
- BP energy statistics 2008 http://www.bp.com/productlanding.do?categoryId=6929&contentId=7044622
- Mauna Loa CO2 data from NOAA http://www.esrl.noaa.gov/gmd/ccgg/trends/co2_data_mlo.html
- C. J. Campbell, The Association For The Study Of Peak Oil And Gas “ASPO” Newsletter No. 100 – April 2009 http://www.aspo-ireland.org/contentFiles/newsletterPDFs/newsletter100_200904.pdf
- The Energy Watch Group http://www.energywatchgroup.org/fileadmin/global/pdf/EWG_Report_Coal_10-07-2007ms.pdf