Because the goal here is not to alleviate a particular symptom but rather to minimize our total impact on the ecology we rely upon to keep us alive.

Bingo.

If it was a natural-cycle, I would say leave it alone and we should adapt. If the cooling was due to our meddling, then I would say let's find the cause of this problem and stop the process of this cause.

I completely disagree. The real question is whether the cooling (or warming, for that matter) is beneficial or harmful to humans.

If the cooling/warming trend is beneficial to humans, we should welcome it with open arms, whether it's man-made or natural. We might even look for ways to speed it up further.

If the cooling/warming trend is harmful to humans, we should think about ways to slow, stop, or reverse it. We should not sit there resigned to our fate just because we didn't cause it.

I mean, heck, if an asteroid's orbit (which is about as natural as things get) caused it to be on a collision course with the earth, we wouldn't be talking about whether human activity caused gravitational disturbances that put it on its current path. "Who the flying **** cares? Let's build a spaceship already to fire nukes at it and knock it off course!"

And this is the point of the question. Is the goal to promote human welfare, or is it to attempt to restore the planet to some sort of "natural" state -- where "natural" is defined, oddly enough, as "the state the planet would be in if humans went extinct prior to the Industrial Revolution, or had the Industrial Revolution never happened." (A particularly odd definition because humans and humans' brains arose from a very natural process called evolution.)

This is the difference between "environmentalism" and "conservationism." Everyone is a conservationist, because conservation is common sense. The definition of conservation is nothing other than "don't be wasteful." Well, duh!

Environmentalism, on the other hand, when you strip it down to its bare essentials, is *not* about human welfare. It's a new secular religion where your religious calling is to minimize your "impact on the planet." (I won't mention the most obvious way to reduce your personal impact on the planet to zero, because it's way too obvious. I leave it as an exercise to the reader.)

Environmentalism is, at its fundamental core, opposed to the idea that man should use technology to shape nature.

I, on the other hand, believe that it is our right to use technology to shape nature however we wish, in order to promote human welfare. Obviously we need to be careful about how we do it (we don't want our use of technology to backfire and make things worse), but I am 100% in favor of climate engineering. Imagine if we had the technology to reshape the earth's climate to make both summers and winters less harsh. I'd be all for it! There would be countless benefits to so many areas of our life. (For starters, agriculture -- no more frozen peach and orange crops.)

as a society that we're top-billing a debate between John Kerry and Newt Gingrich, neither of whom - to my knowledge - have much experience with climatology research.

Or that Michael Crichton is considered an authority for climate-change denial, which is understandable given his background as a doctor. I suppose next we'll ask meteorologists to perform open-heart surgery, since the two are apparently interchangeable.

This is as much a debate as evolution/creation is a debate: not in any sane meaning of the word.

I think a better question is: outside of its cheapness, what is the benefit to using carbon fuel instead of solar, wind, or thermal?

Energy density. Fossil fuels contain an amazing amount of punch for their size/mass. Unfortunately solar/wind/geothermal are simply incapable of replacing fossil fuels at their current rate of use.

Which is a good argument for dramatically curtailing our energy usage.

And be done with it for a while. Here is a plan I salvaged from a previous post (in response to tlaloc) that puts together a 20 year plan to completely eliminate fossil fuel emissions world-wide AND the US can be Kyoto friendly during those 20 years to boot!

Nope, reread the source it says at *current* usage rates, not prjected. Our energy usage has been increasing year by year. in fact I used the BP figure linked to in that Wiki article to go ahead and recalculate assuming that the rate of energy increase stays liner and that cuts the estimate to about half. Now here's a couple things to say about that:

1) linear growth is overly optimistic, a logaritmic model is more realistic and will consequently cut that down further.
2) Those are based on coal estimates, not proven reserves and the energy companies have a long history of wildly inflating their estimated reserves because it is like printing free money, say you have a large "unproven" reserve and your stock goes up, or at least doesn;t go down like admitting that the reserves are tapped would do. Based on the history of oil "estimates" I'd recommend taking any industry estimate and cutting it in half to be on the safe side.
3) as opposed to oil coal has to be mined. Mining is heavily energy intensive since it requires moving vast amounts of heavy earth and rock to get at the (also heavy) ore.
4) the Fischer-Tropsch process of converting coal to a faux oil is generally less than 50% efficient.

So take the estimate of coal lasting 600 years, cut it to 400 years for more accurate energy use, cut it to 200 years for more realistic reserves, cut it to 100 years when you figure in losses when converting to an oil substitute, and now cut it to less than 100 years when you figure in the greater difficulty of mining and transporting coal as opposed to oil.

Sure, add in whatever assumptions you want to make the estimates come out the way you want, but don't complain when I do the same thing.

Do you get it? Only 17 ZJ of uranium fuel. The 2500ZJ figure comes from the idea of using breeder reactors which essentially reuse the fuel over and over to get every last bit of potential energy out of them.

So let's revisit this issue based on my making the assumptions, shall we?

(1) I will assume that the IAEA (a favorite organization among the left, BTW) is competent to make these assessments because that are the internationally recognized "experts" in this area.

(2) Given (1) I assume that we have on the order of 2500ZJ of nuclear fuel for breeder reactors, and on the order of 17ZJ of nuclear fuel for once through use.

(3) Given that you are (a) comfortable with the use and development of Nuclear Energy, and (b) aware of the absolute urgency to take action quickly, I assume that you will be 100% on board with the development and deployment of Fast Breeder technology ASAP.

(4) Given (3) I assume that you will devote your time and effort to tirelessly use you vast powers of persuasion to convince the left-wing nut-case ecologists that Nuclear Energy is nothing to be afraid of and that due to the impending decline of fossil fuels we need to pursue it as quickly as possible. I further assume that you are successful in removing any concerns these people might have and further that they are so convinced of the need that they volunteer to man the hippy-style sit-ins required to provoke Congress into action.

(5) Given (3) and (4) I assume that you will support using that 2% GDP savings we got by blowing off kyoto to invest in the building of Faster Breeder reactors as quickly as possible.

(5a) If you find that you simply CANNOT stomach ignoring kyoto, I assume that you are OK with using some portion of the 2% GDP to purchase the credits under kyoto from under-developed or otherwise low-polluting countries to allow us to proceed for 10-20 years without any other infrastructure changes required for the fossil fuel based energy sources. So then we have kyoto covered nice and tidy.

(6) I assume that we will make sufficient investments in other available alternative energy sources based on already existing technologies (excluding Nuclear) to meet the need for any additional growth in consumption over the next 10-20 years.

(7) I assume that (6) is financed using Carbon Credits purchased by left-wing nut-case ecologists that are in turn invested in the required development of alternative energy sources.

(8) I assume that, consistent with (4) you will likewise use your vast powers of persuasion to convince the left-wing nut-case ecologists to forego any objections to (6) and (7) for the greater good of humanity and the planet as a whole.

(9) Consistent with (6) I assume that our current rate of Nuclear Fuel consumption of 0.03ZJ/year remains constant for the next 10-20 years.

(10) Consistent with (9) over the next 20 years we will burn up approximately 0.6ZJ of the available nuclear fuel leaving approximately 16.4ZJ of usable fuel remaining. This represents a (0.6/17)*100 = (approximately) 3.5% reduction in available fuel.

(11) Consistent with (10) I assume that in 20 years hence we will have approximately 2500 * 96.5% = 2412.5ZJ of nuclear fuel remaining if Fast Breeder reactor technology is on-line by then.

(12) Given that prototypes up to a capacity of 1000MW already exist , and that other Fast Breeder reactors have already been built and operated (see "Successful LMFR plants have been designed, constructed and operated, e.g. the BN-600 in Russia, the 1200 MWe Superphenix in France, and the 280 MWe Monju in Japan"), I assume that with a concerted effort production quality plans will be ready and construction can begin on whatever suitable number of reactors in required to completely supplant fossil fuel usage well within 5 years.

(13) Consistent with (5), (6), (8), and (12) I assume that the required number of nuclear plants to completely supplant fossil fuels are available within 20 years.

(14) Given the estimate of a worldwide annual growth rate of 2% between 1980 and 2004 , I assume that growth rate remains constant moving forward.

(15) Consistent with (14) the computation for the total accumulated energy consumption over time should look rather like the financial computation for an annuity. Thus, we have:

Growth Factor R = 1 + 0.02 = 1.02
Current Consumption Rate CCR = 0.5 ZJ/year

Total Energy Consumed TEC(t) = CCR * ((R^t - 1) / (R - 1))

We are interested in finding t where TEC(t) = 2412.5 ZJ (from 11 above)

TEC(t) = 2412.5 = 0.5 * ((1.02^t - 1) / (1.02 - 1))
==> 2412.5 / 0.5 = ((1.02^t - 1) / (1.02 - 1))
==> (2412.5 * (1.02 - 1)) / 0.5 = 1.02^t - 1
==> ((2412.5 * (1.02 - 1) / 0.5) + 1 = 1.02^t
==> logn( ((2412.5 * (1.02 - 1) / 0.5) + 1 ) = t * logn( 1.02 )
==> t = logn( ((2412.5 * (1.02 - 1) / 0.5) + 1 ) / logn( 1.02 )
==> t = logn( 97.5 ) / logn( 1.02 )
==> t = 231 years and change

This is a VERY conservative estimate as it accounts for an increase in energy usage from our current 0.5ZJ/year to 0.5 * 1.02^231 = 48 ZJ/year by the year 2258 (i.e. 2007 + 20 + 231). Personally I consider that absurd but you claimed the exponential growth would be more accurate so there you have it.

(16) Consistent with (5) the current GDP is approximately $13 Trillion . 2% of that would be $260 Billion. Assuming a conservative 3% annual growth rate over the next 20 years this should yield about:

$260B * ((1.03^ - 1) / (1.03 - 1)) = $6,986B over the next 20 years.

(17) At the current cost of about $5B (as of 1980s) the revenue generated by (16) should provide about 1400 brand new Breeder Reactors, or about 1050 if you assume only 75% of the money actually goes toward building new reactors.

(17a) Consistent with (5a) reduce the number of purchased reactors accordingly.

(18) Consistent with (12) if the number of reactors required to meet global requirements is greater than that provided in (17) and/or (17a) I assume that the rest of the world will buy their own friggin' reactors.

Now, this was fun and all. And the 231 year estimate is lower than I would have expected, but still allow plenty of time to find ways to better harness the sun. Since you like to hear from the experts let's see what the IAEA has to say on this topic:

Uranium 2005: Resources, Production and Demand - also called the "Red Book" - estimates the total identified amount of conventional uranium stock, which can be mined for less than USD 130 per kg, to be about 4.7 million tonnes. Based on the 2004 nuclear electricity generation rate of demand the amount is sufficient for 85 years, the study states. Fast reactor technology would lengthen this period to over 2500 years.

However, world uranium resources in total are considered to be much higher. Based on geological evidence and knowledge of uranium in phosphates the study considers more than 35 million tonnes is available for exploitation.