Hubbert's Theory
The contemporary concept of peak coal follows from M. King Hubbert's Hubbert peak theory, which is most commonly associated with Peak oil. Hubbert's analysis showed how each oil well, region, and nation has a depletion curve. However, this question was originally raised by William Stanley Jevons in his book The Coal Question back in 1865.
Hubbert noted that United States coal extraction grew exponentially at a steady 6.6% per year from 1850 to 1910. Then the growth leveled off. He concluded that no finite resource could sustain exponential growth. At some point, the rate of extraction will have to peak and then decline until the resource is exhausted. He theorized that extraction rate plotted versus time would show a bell-shaped curve, declining as rapidly as it had risen. Hubbert used his observation of the US coal extraction to predict the behavior of peak oil.
The Hubbert Linearization using yearly production rates has minor weaknesses for peak coal calculation, as the signal-to-noise ratio is inferior with coal mining data compared to oil extraction. As a consequence, Rutledge uses cumulative production for linearization. By this method the estimated ultimate recovery results in a stable fit for active coal regions. The ultimate production for world coal is estimated to be 680 Gt, of which 309 Gt have already been produced.
Read more about this topic: Peak Coal
Famous quotes containing the word theory:
“Thus the theory of description matters most.
It is the theory of the word for those
For whom the word is the making of the world,
The buzzing world and lisping firmament.”
—Wallace Stevens (1879–1955)