The Oil Drum

This is a guest post by Dave Rutledge, Chair for the Division of Engineering and Applied Science at Caltech, which has 12 departments with 75 faculty members and 500 graduate students.

Dave is fascinated by the possibility that the key to understanding the future of world coal production may be in the history of the mining areas in the northern Appalachians and the north of England. Dave is also interested in the question of how California will make the transition from fossil fuels to renewable fuels for electricity production.

At The Oil Drum, there has been much discussion of the modeling of future oil production and the reliability of reserve data. It is also understood that burning fossil hydrocarbon fuels increases the CO2 concentration in the atmosphere, and that this is likely to affect our climate. What about coal? Can we figure out how much coal is likely to be produced, and how quickly the coal reserves will be exhausted? How reliable are coal reserve numbers? What can our models for coal and hydrocarbon production tell us about atmospheric CO2 concentrations? About climate? It turns out that we can give answers to all of these questions, using the same Hubbert linearizations and normal curve fits that we use for oil.

The importance of these approaches to estimating future production is emphasized by this astonishing statement in the pre-publication version of the National Academy of Sciences Report on coal, released yesterday:

Present estimates of coal reserves are based upon methods that have not been reviewed or revised since their inception in 1974, and much of the input data were compiled in the early 1970s. Recent programs to assess reserves in limited areas using updated methods indicate that only a small fraction of previously estimated reserves are actually minable reserves.

2007 sees the staggered release of the Intergovernmental Panel on Climate Change’s (IPCC) 4th Assessment Report. The first part of which was released on Friday 2nd February. This "Summary For Policy Makers" is available here (.pdf) and at just 21 pages is certainly worth reading.

Column yards have been written about it already, I’m just going to offer brief comment on a single extract spread over pages 12 and 13. (GtC = billions tonnes of carbon)

Based on current understanding of climate carbon cycle feedback, model studies suggest that to stabilise at 450 ppm carbon dioxide, could require that cumulative emissions over the 21st century be reduced from an average of approximately 670 [630 to 710] GtC to approximately 490 [375 to 600] GtC. Similarly, to stabilise at 1000 ppm this feedback could require that cumulative emissions be reduced from a model average of approximately 1415 [1340 to 1490] GtC to approximately 1100 [980 to 1250] GtC. {7.3, 10.4}