Comments on: Positive & Welfare Effects of Carbon Taxes: Some Basic Economics*

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By: robot cuisine

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By: Tim Curtin

Tim Curtin — Wed, 31 Mar 2010 03:35:50 +0000

hc: I really would like your comments on my last, as I am writing it up for a new paper. Would your journal be interested?

By: Tim Curtin

Tim Curtin — Tue, 30 Mar 2010 06:51:55 +0000

hc: thanks for your kind thoughts. You are wrong about CO2 and photosynthesis, as it is not a question of the incremental yield effect of incremental [CO2] on a particular crop, but of NPP itself across the board of all crops if [CO2] is driven back to 1750 levels as you seem to want, in the absence of your definition of the optimal level of [CO2]. Surely you have enough economic history to know that gross NPP of food crops in 1750 for a global population of less than a billion was hugely less than it is today for a population of nearly 7 billion. McChance in his classic paper of 1945 shows how the average energy content of English and Canadian wheat was of the order of 377 kg cal. per 100 grams of whole wheat. Where does that energy come from?
A much later study from Japan (by naka0310@affrc.go.jp) gives these factors for Total Carbon content (T-C): carbohydrate 45%, protein 53%, fat 77%. Do look at any packet of cereal in your kitchen. Our Spelt flakes have 392 kcals of energy per 100 grams and 7.8 g of protein, of which T-C is 53%, 78.7 g of carbohydrate per 100 grams, of which T-C is 45%, and fat 6 g, of which T-C is 77%. I make that aggregate T-C of 43 grams per 100 grams and for our rice flakes the figure is 41 g/100g. Where does that carbon come from?
The FAO’s data on global cereal production in 1960 (rice milled eqv) was 805 million tonnes for a world population of 3 billion; by 2007 it had much more than doubled to 2,125 million tonnes, and world population had risen to c6.5 billion. The respective carbon content was 338 and 893 million tonnes. Remember these are annual crops, so it is reasonable to compare these figures with annual emissions from fossil fuel burning, at 2.4 GtC in 1960 (Le Quere 2008), of which 14% was evidently accounted for by just world cereal (mainly wheat and rice) production, and the emissions figure in 2007 was 8.06 GtC, of which 11% accounted for by T-C. But the world’s people do not live by bread and rice alone, and their consumption of meat and fish has risen much faster than that of cereals. Believe it or not, the T-C content of beef, pork, fish, and, dare I say it, whale meat, is very large. Total uptakes of all emissions by the biosphere have actually averaged 57% from 1958 to date, so the cereals proportion is a small part of the whole.
Dear hc, I think it is for you and the likes of Will Steffen (except he can’t) to explain what the impact of reducing emissions by 60% of the 2000 level, to 2.6 GtC will be, when that is compared with the carbon content of just world cereal production in 2007 of 0.893 GtC. Even C4 crops like maize and savannah grasslands will struggle to get by, so much for Garnaut’s roo steaks.
And as Graham Farquhar explains patiently to any who will listen (not many at ANU), the CO2 fertilisation effect heavily depends on its partial pressure at ground level, which you and Hansen are hell bent on reducing to the 1750 level.
I know you will never believe me, but do try Graham, as in his Royal Society paper (2008), which directly addresses your temperature point:
Phil. Trans. R. Soc. B doi:10.1098/rstb.2007.0032Effects of rising temperatures and [CO2]
On the physiology of tropical forest trees. Jon Lloyd1,* and Graham D. Farquhar2
1Earth and Biosphere Institute, School of Geography, University of Leeds, Leeds LS2 9JT, UK
2Environmental Biology Group, Research School of Biological Sciences, Australian National University,
Canberra, Australian Capital Territory 0200, Australia
Using a mixture of observations and climate model outputs and a simple parameterization of leaf-level photosynthesis incorporating known temperature sensitivities, we find no evidence for tropical forests currently existing ‘dangerously close’ to their optimum temperature range. Our model suggests that although reductions in photosynthetic rate at leaf temperatures (TL) above 308C may occur, these are almost entirely accountable for in terms of reductions in stomatal conductance in response to higher leaf to-air vapour pressure deficits D. This is as opposed to direct effects of TL on photosynthetic metabolism.
We also find that increases in photosynthetic rates associated with increases in ambient [CO2] over forthcoming decades should more than offset any decline in photosynthetic productivity due to higher D or TL or increased autotrophic respiration rates as a consequence of higher tissue temperatures. We also find little direct evidence that tropical forests should not be able to respond to increases in [CO2] and argue that the magnitude and pattern of increases in forest dynamics across Amazonia observed over the last few decades are consistent with a [CO2]-induced stimulation of tree growth.
Keywords: review; photosynthesis; climate change; plant growth

By: hc

hc — Mon, 29 Mar 2010 10:48:05 +0000

Tim, CO2 isn’t toxic waste – there is just too much of it in the atmosphere creating a heating effect having risen from around 280 ppm since preindustrial times. There are some plant species than gain growth from the extra CO2 but all lose out when warming effects are large enough. The reason that you are rejected from the ANU is that you come across as a fanatic. You are hostile to the idea of climate change when most of us accept the reality of likely harmful warming and want to do something about it. Time to move on.

By: Tim Curtin

Tim Curtin — Sat, 27 Mar 2010 11:39:15 +0000

hc: it is a week now, and still no rejoinder from you to my comment on what you said “Tim you are continuing with the foolish line that supporters of the global warming hypothesis are denying photosynthesis. Tedious.” Really? so reducing atmospheric CO2 to 350 ppm or less (Hansen) will have no effect on photosynthesis? Your reply was nothing more than arm waving.

Harry, I really would like your considered opinion on the follwoing points, hwoever “tedious” you amy find them, a view that I doubt is shared by hungy people in Africa, India and even China.

Harry, however tedious, it is a fact that 57% of CO2 emissions since 1958 have been taken up by the biosphere, including us by the food we eat, ALL of which derives from photosynthesis using the CO2 you consider to be toxic waste. And by “us” I include the extra 4.5 billion of us now around since 1950, all of us subsisting on CO2-based food (even your lifestyle preumably includes some wheaties or similar of which 80% consists of carbohydrtaes, where did they come from?). Somehow most of us nearly 7 billion now do eat (if we didn’t, a la Ehrlich and Holdren, we wouldn’t be 7 billion) – but what will we eat when living in your nirvana of a carbon-free economy? The rising partial pressure of CO2 arising from growing atmospheric CO2 has made a powerful contribution to yields of both phyto-plankton/krill (for whales and dolphins et al) and wheat and rice for us 7 billion (see Graham Farquhar, passim, and another 2,000 citations I have on the link between atmospheric CO2 and food production). Please name your citations for no such link.

By: Tim Curtin

Tim Curtin — Mon, 22 Mar 2010 11:00:26 +0000

hc: still no response from you to my last? You are in good company, Ross G and his co-authors Stephen Howes & Frank Jotzo (along with Will Steffen) also have no reply, eg to my Quadrant article last year, and Stephen after not a few direct interactions. Because they have nothing to offer in response, my peer-reviewed paper “Climate Change and Food Production” is banned at the ANU (or at least my 4 separate offers of seminars on it (including to Crawford, WS and the Fenner School), have yet to be accepted, WS & FS rejected outright. Truly the little Emperors at ANU and yourself have at best only scanty clothing.

By: Tim Curtin

Tim Curtin — Sat, 20 Mar 2010 12:14:34 +0000

hc: prove that they are not. I heard Will Steffen attempt that at Shine Dome here about 2 weeks ago, but he is incapable of understanding the difference between CO2 raising the yield of a specific crop and allowing the NPP of a new crop planting or new variety (or forest). Do you ever read anything contrary to your own world view? Try Wigley, one of your own true believers: Wigley Tellus & with Enting CSIRO 1993 rejects the logarithmic form for projecting uptakes of CO2 by the biospheres:

NPP= (No(1+beta*ln(C/Co)) …A1

in favour of

NPP = [(No(C-Cb)(1+b(Co-Cb))]/[(Co-Cb)(1+b)(C-Cb))] .…A2

Wigley’s A1 “allows NPP to increase without limit as C increases” (which has always been the case so far, see Curtin 2009 and Knorr GRL 2009) so he says it should be replaced by A2, whose hyperbolic form ensures that NPP reaches a ceiling with respect to increases in [CO2], and then declines around 2000 according to WG1 and Meinshausens et al in Nature 30 April 2009, for which there is no evidence, see Knorr W., GRL, 2009, if you don’t believe me. Allen et al’s contribution in Nature 30 April 2009 is to make Wigley’s A2 quadratic so we should already be seeing declines in total world NPP. Do we?

It is A2 and its built-in ceiling on increases in NPP that determines the projections in MAGICC which was developed by T.G.L.Wigley, S. Raper and M. Hulme (all of CRU/UEA) and is available at http://www.cgd.ucar.edu/cas/wigley/magicc/index.html.

WG1 of IPCC AR4 describes its use of MAGICC in 8.8.2 to generate all its projections of “warming” to 2100 and beyond. I have MAGICC and it has no module for overrruling A2, and thus has its limitations as a computer game, which is all MAGICC is, and a very bad one at that.

hc: you said “Tim you are continuing with the foolish line that supporters of the global warming hypothesis are denying photosynthesis. Tedious.”

“Solly tumas” as my PNG mates would say. But if those supporters do not “deny photosynthesis”, why do they believe it would not be affected by either reducing the present atmospheric concentration of CO2 from c389 ppm to 350 ppm, or eliminating all emissions of CO2, as demanded by James Hansen?

Try reading some papers by Graham Farquhar before you reply.

By: hc

hc — Wed, 17 Mar 2010 16:52:04 +0000

Tim you are continuing with the foolish line that supporters of the global warming hypothesis are denying photosynthesis. Tedious.

By: Tim Curtin

Tim Curtin — Tue, 16 Mar 2010 01:02:19 +0000

So CO2 is a negative externality? what would world food production be in the absence of that free positive eternality, atmospheric CO2, without which we would none us be around? Check out my Einstein “letter” in RES at my website to see how quickly atmospheric CO2 disappears in the absence of emissions and continuing biotic absorption (endorsed by Graham Farquhar who says it is worse than that, as declining partial pressure of [CO2] (say to 350 ppm) itself reduces photosynthetic uptakes by land and sea, so yields collapse).