The UnAustralian

Thursday, June 12, 2003
 
More On Global Warming: Part 2

Ken's attack on the IPCC emission scenario's doesn't end there. He carries on with:

An equally important source of exaggeration in the IPCC scenarios is that both the A2 and B2 storylines (the lower economic growth storylines) mostly assume that oil will run out by about the middle of the century, and that third world countries will simply move to (higher CO2-generating) coal as their main source of energy. The B2 storyline at least assumes that the first world will make some efforts to move to cleaner energy technologies (like natural gas). Hence it achieves markedly lower emission outcomes than the A2 storyline, which shows CO2 emissions at stratospheric levels. Essentially it is the A2 storyline that results in the really scary future temperature projections such as claims of temperature rises of 5 degrees C by 2100. All other scenarios, including B2, result in much more modest (though still exaggerated) outcomes (although there are some individual A1 scenarios that also reach stratospheric emission outcomes, again mostly by assuming exhaustion of oil and conversion to coal).

In fact, although current world oil reserves are projected to last around 60 years or so, those reserves figures don't include the relatively plentiful natural gas reserves (a cleaner fuel than oil). Nor do they include Canada's oil sands deposits which, at an estimated recoverable 1,700 billion barrels in total, are believed to be larger than Saudi Arabia's oil reserves.

Firstly, the IPCC do not predict than oil will run out in the middle of the 20th century for any scenario. Rather, as it becomes harder to obtain oil, the price will rise, leading to a decrease in the amount of energy derived from oil. The next error in this section of Ken's posts is also related to this point. No, the IPCC don't include natural gas in there estimates of the world's oil supplies. Rather they give it's own category. The next error, is too do with oil sands. The IPCC divides the world oil supplies into two categories, conventional and unconventional. Conventional oil supplies are what we drill today, unconventional are what we will drill tomorrow. These unconventional sources include oil sands and shales.

Ken also, IMHO, exaggerates the warming effect of the A2 scenario relative to the other scenarios. The average surface air temperature rises for the various scenarios are:

A1B: 2.95
A1T: 2.54
A1F1: 4.49
A2: 3.79
B1: 1.98
B2: 2.69

While the A2 scenario has a large rise, it isn't super high compared with the other scenarios.

Finally, Ken highlights a potential new technology, which could significantly reduce the CO2 outputs of coal. That technology will play a major role in our future is already well known to the IPCC. All of the scenarios have significant effects due to technological change.


| 8:40 PM