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April 16, 2006

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Sam Grove

Re: computer development
There may be a hard limit in chip power as we currently conceive them, however, we are seeing the beginning of new ways to utilize chips such as dual core. In time, computer power will enable the expansion of this mode into into massive parallel computing devices or perhaps something yet to be conceived.
Look how far we've come. When I studied electronics in the early 70s, I used a slide rule and log tables to perform calculations. In the early 90s, I purchased a 33MHz computer with 4MB of RAM and a 208M hard drive for $1800.
The thing to remember is: don't rely on straightforward extension of current technology. It's going to be a surprise.

Mark Bahner

Hi Heiko,

You write, "You are very harsh in the wording of your comments over on Prometheus."

Yes, I don't appreciate at all "Dano's" or Andrew Dessler's insults. And I don't appreciate Andrew Dessler's lies about my work.

Environmental analyses are what I do for a living. I don't mind at all when people disagree with my analyses...even strongly. But it is simply not acceptable for anyone--and I mean anyone--to ridicule my analyses...especially when they can't even come up with their own competing analyses. I've repeatedly asked Andrew Dessler and Dano to come up with their own analyses--in fact, I've offered to pay them to do so--but they've refused. That is completely unacceptable to me.

"Extrapolation is a tricky business. If there's a break in nat gas/oil prices, without killing China's/India's economy, why shouldn't carbon intensity rise and carbon emissions head to several times the present level."

Yes, extrapolation is tricky. But it's far less susceptible to nonsense predictions than inventing "scenarios" that essentially invent an entire world that exists only in a computer.

For example, why would there be a break in nat gas/oil prices, at least in the forseeable future (i.e., next 5-10 years)? And if there is not a break in natural gas/oil prices in the next 5-10 years, don't you think that will really accelerate the development of oil-saving and natural-gas- saving technologies, such as plug-in hybrid vehicles and natural gas fuel cells for residential electrical generation?

"As for computing power and economic growth, there might be some hard limit. So instead of continuing to improve exponentially, growth (at least for the capabilities of microchips) might rapidly decelerate towards a near nigh fixed ceiling."

Yes, that's *possible,* but it seems very unlikely to me. Have you read any of the work of Ray Kurzweil (especially books like, "The Age of Spiritual Machines" and "The Singularity is Near")? In my opinion he makes a very strong case that development in computers is accelerating, not decelerating.

But we'll know whether I (and Arnold Kling, Ray Kurzweil and others) am right, or most of the economic community is right, within the next 10-20 years. I predict that, after 2020, annual per-capita world growth rates above 4% per year will be common.

Mark Bahner

Hi Heiko,

You write, "If you disaggregate the data into developed world/developing countries, you'll find something like steady per capita energy for the developed world, steady per capita energy for the world as a whole, and a fifty percent increase for developing countries. The world average stayed steady, because virtually all the population increase happened in the developing world."

I don't see the logic there. If the increase in population occurred in the developing world, and the increase in per-capita use occurred in the developing world, it seems like there should be an increase in per-capita use.

I think the reason there hasn't been an increase is because the per-capita use in the developing world is so low.

You write, "I like the IPCC scenarios,..."

Scenarios don't make sense as a method for predicting the future. Suppose you jogged every night, and averaged about 4 minutes a kilometer. If you predicted what your times would be in the next week or two, would you invent a scenario where you broke your leg, or suddenly started running kilometers in 2.5 minutes? Scenarios are instead useful in *reacting* to acute future events.

I agree that analyzing in different ways, as with the varying methods of disaggregation that you suggest, is potentially useful. But simply inventing scenarios that have no link to past is not scientific at all.

"The high end IPCC scenarios assume huge coal use after 2050."

Yes, exactly. That's totally crazy. It completely ingores the whole history of energy development. The world will increasingly move *away* from coal as the 21st century progresses, not toward it.

Heiko Gerhauser

You are very harsh in the wording of your comments over on Prometheus.

Extrapolation is a tricky business. If there's a break in nat gas/oil prices, without killing China's/India's economy, why shouldn't carbon intensity rise and carbon emissions head to several times the present level. There's enough coal for that, and as long as China/India have the coal, the need for the coal, and believe it's cheaper than nat gas/oil/nuclear/renewables, why discount the possibility they might use it in the scenario building?

As for computing power and economic growth, there might be some hard limit. So instead of continuing to improve exponentially, growth (at least for the capabilities of microchips) might rapidly decelerate towards a near nigh fixed ceiling.

Heiko Gerhauser

If you disaggregate the data into developed world/developing countries, you'll find something like steady per capita energy for the developed world, steady per capita energy for the world as a whole,
and a fifty percent increase for developing countries.

The world average stayed steady, because virtually all the population increase happened in the developing world.

If you disaggregate like this and project trends I think you should find higher values more believable.

I like the IPCC scenarios, but I also think that it needs to be made much clearer how important the emission scenarios really are for the temperature projections. The high end IPCC scenarios assume huge coal use after 2050.

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