1. IPCC scenario coal production is too high

And the effect of this is what? Perhaps the authors of this paper or Rutledge could post HL graphs, etc., using the IPCC URR(s) vs. the ones in this paper?

I wonder because adding large amounts of URR to HLs for crude change the peak almost not at all for all practical purposes. Is it the same with coal? If so, the economic effects of IPCC overestimates aren't likely to be important.

3. Given the enormous difficulties in developing energy infrastructure in terms of time and money, encouraging alternatives for electricity is a good idea, regardless of what you think about climate.

Referring back to #1, it doesn't matter if the IPCC has overestimated reserves if climate sensitivity is greater than, even double, 3C as the positive effects of having less coal to burn are made up by the fact that the 3C sensitivity is as much as half of what observations suggest. In fact, I doubt IPCC-stated reserves are more than double those here (I'm confident you will correct me if wrong), so we still end up with a massive problem if 3C is low.

The solutions chosen are not independent of considerations of Anthropogenically-driven Climate Change because not all solutions are good for both energetic and climate issues. We must be careful about dismissing ACC.

Cheers

Hi ccpo,

The maximum cumulative in an IPCC scenario through 2100 is 3,400Gt (at 21GJ/t), and in that scenario, production is still rising in 2100. This implies an ultimate of around 7,000Gt or more.

Dave

Reading through this thread one thing becomes clear: there is less certainty about coal reserves than about either PO or ACC, which is fascinating. I'd have thought coal reserves would be more easily quantified than oil.

The 7 trillion vs. 1.2 trillion spread is pretty wide and worth investigating, but given the uncertainty about coal reserves and the time left to act (Hirsch, et al. 2005), it's an academic question, at best. Decisions about energy and climate will need to be made long before verifiable numbers for coal are ever determined.

We come back to risk assessment. Is it worth the risk that there *aren't* enough coal reserves, that there *isn't* enough CO2 to push us into catastrophic climate changes, that tipping points are happening now... etc?

I don't see how it is.

Besides, what are generations a hundred, two hundred, five hundred years from now supposed to use for energy? Etc.

That is, I think the discussion is moot wrt policy. We have no choice. And if we don't act, we risk it all. Those aren't odds I'm interested in.

Cheers