CO2 Science has a good editorial in this week's edition criticising the chairman of the IPCC for stating his doom-laden predictions as already established fact.
We wish Pachauri had mentioned what those already-experienced "most serious consequences" were. Has the earth warmed by a frightening amount? Absolutely not. The increase in temperature over the last century or more is only on the order of 1°C. Has it taken us to an unusual level of warmth? Absolutely not, as evidenced by the fact that the baseline from which modern warming commenced was the uncharacteristic cold of the Little Ice Age, which is judged to have been the coldest interval of the current interglacial, which has itself been deemed to have been colder than all four of the interglacials that immediately preceded it (Petit et al., 1999). Clearly, therefore, we are in the process of emerging from perhaps the coldest period of the past half-million years; and we may yet have a ways to go before we return to what would be considered a more "normal" interglacial climate.
The editorial points out that, far from having serious consequences thus far, CO2 has been significantly responsible for helping plants grow more vigorously and profusely.
This phenomenon has been a great boon to humanity, and especially to "the sustainable well-being of rural communities" that ranks so high on Pachauri's list of important causes he says he supports, and for whom crop growth and vitality are of critical importance. Interestingly, however - and tellingly - he recoils against one of the most powerful forces at work in the world today that is helping to bring about that to which he pays such fervent lip service, and which has a proven track record of impressive accomplishment.
And what is that record? In our editorial of 11 Jul 2001, we describe how the Industrial Revolution's flooding of the air with CO2 has likely already resulted in mean yield increases of 70% for C3 cereals, 28% for C4 cereals, 33% for fruits and melons, 62% for legumes, 67% for root and tuber crops, and 51% for vegetables, all due to the aerial fertilization effect of atmospheric CO2 enrichment and its concurrent anti-transpiration effect, which together greatly enhance plant water use efficiency.
Those are significant increases, but are they really that important?
Not only do these phenomena benefit people everywhere, they are also of great benefit to the planet's terrestrial animals, and not only because they enhance the vegetative food base that ultimately sustains all of them, but because without the boost atmospheric CO2 enrichment gives to human agricultural production, in just a few short decades it has been estimated that humanity will have to usurp nearly all remaining cultivatable land and freshwater resources on the face of the planet just to produce the food needed to sustain our own species, leaving next to nothing for what we could call wild nature. See, in this regard, our reviews of Wallace (2000), Tilman et al. (2001) and Foley et al. (2005).
The way I read that is that there are two possible scenarios in a world with considerably less CO2. One) we either cultivate every bit of land that we can to sustain the world's human population and so wipe out significant species of plant and animal - which would be a real catastrophe for the biodiversity our politicians like to bang on about - or two) the human population has to decline considerably inside a few decades.
Not a great choice really. I've been reading CO2 Science for a while now and they generally don't get too worked up in their editorials, generally preferring a more analytical approach to the debate rather than wading in with both barrels blazing. So to read this editorial came as a bit of a surprise to me. However, having looked through a couple of articles in this weeks issue as well it looks like they are beginning to tire of the constant drip drip of the patently false propaganda being put out by the AGW supporters.