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Wednesday, December 14, 2005

Symmetry: The Eye of the Beholder

As a rule, humans would rather deal with symmetry than asymmetry in their day-to-day lives. Pragmatically, it really boils down to having to deal with half the information than one would normally have to face under skewed circumstances. Psychometrically, it means you only have to process half the visual data and automatically mirror reflect the rest via the brain's powerful built-in DSP hardware. I haven't thought about this in the context of oil depletion for awhile, but this post from peakoil.com concerning Campbell's discovery plot board got me thinking.
I have read this entire thread from start to end. It is a huge, huge shame that what started out as a civil conversation has taken such a sour turn thanks to a few doomers who feel that personal attacks will silence the optimists.

Mr. Lynch - thank you for your time on this thread - lots of great stuff!!

With regards to this chart, I spent the past hour doing a year by year analysis. I will admit I rounded to the nearest whole number so the numbers may not be 100% accurate but fairly close. For the consumption numbers I used the same chart on LATOC that has consumption line drawn from 1930 to today.

Here is what I came up with:

Total Discoveries 1930-2005: 1.814 billion barrels
Total Consumption 1930-2005: 1.052 billion barrels

Some interesting points of interest from the chart:

1) It is my understanding that it takes roughly 10 years to get a new discovery online. Based on this, the chart says in the past 10 years, 123 billion barrels were discovered - which has yet to come online. I could be off on the 10 years but the point is it is not all online yet as of now.

2) The chart estimates that we have 137 billion barrels of oil of yet to be discovered oil between today and 2050.

Now for the problems I have found with this chart (and why I believe it to be a Peak Oil doomer scam):

1) According to the chart, we should only have around 760 billion barrels of oil left in the ground, yet most proven reserve estimates I have seen say we have at between 1.000 to 1.278 trillion barrels (depending if you count the Tar Sands in Canada or not).

2) Assuming worldwide Peak Oil is the point at which we consume 50% of the oil in the ground, Peak Oil should have happened in the year 2000 yet we have continuted to produce more and more oil. This also does not take into account that the new oil discovered in the past 10 years are not online yet (which should have put Peak Oil around 1997).

3) This chart does not account for the 5 trillion barrels of unconventional oil in the world (of which we can get around 1.1 trillion barrels of oil with current technology).
The bolded part (emphasis: Mine!) apparently causes certain people lots of grief. Actually, only the most rudimentary models of oil depletion assume a symmetric production profile. By inspection one can see that the 50% consumption point obviously occurs at the peak for the Logistics curve, Gaussian normal, and other symmetric profiles. This in fact has become the conventional wisdom among certain analysts.
Gas-peak detractors
William L. Fisher, director of the school of geosciences at the University of Texas at Austin, contends that application of the Hubbert curve for resource assessment or for projection of production peaks is "seriously flawed."

"It assumes that the amount of oil or gas is known, which it is not. It assumes that the peak will come midway through the production of the resource, thus the symmetry of the curve, which is not necessarily the case. It also assumes that resources are inelastic, not responding measurably to economics and technology."
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However, if we use a more realistic model for oil production from discoveries, the production profile is asymmetrically weighted for any symmetric discovery profile. The asymmetry provides a much longer ramp-down time than ramp-up time assuming a fixed Markovian extraction rate. This necessarily pulls the peak in closer than a symmetric profile would. The fact that the oil shock model most naturally follows the gamma distribution (Red curve below) also supports this observation.

I suppose you could use the 50% consumption point to estimate peak if you needed something in a pinch, but if you can follow and understand the mathematics behind stochastic processes, conventional wisdom takes a hit.

Asymmetry: Deal with it!


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