Bonmot

Thank you. I know how logs work and I share your belief that Raredog knows exactly what he is doing.

Take for example his claim that anthropogenic CO2 has only a 4.45% effect on global warming. How does he come to this conclusion?

First he asserts that …. “anthropogenic CO2 accounts for just 4.45% of the annual atmospheric turnover – it therefore only has a corresponding 4.45% influence on the 0.12°C mentioned above, at any one time – in other words the effect is negligible.”

He then claims that annual anthropomorphic carbon emissions are 6 giga-tonnes. The last time I looked those emissions were 31 giga-tonnes and rising. He then divides 6 giga-tonnes of carbon by 135 giga-tonnes of CO2 supposedly recycled each year (assuming the atmospheric CO2 pool is 750 gig-tonnes and stable. It isn’t) and hey presto! 4.45%.

Carbon and CO2 are of course not the same thing. It’s rather like dividing apples by oranges and getting lemons. A scientific approach would you say Grahame?

AoM: My last couple of posts went awry, the problem with trying to do too many things at once. Anyway, the gist was there for anyone with patience to follow.

I think Raredog’s reliance on a 1985 publication (Sundquist) is misleading, particularly the calculations based on it. I think you are right and I too am baffled by Raredog's;

“these studies show that CO2 has an average atmospheric lifetime of about five years and that approximately 135 giga-tonnes (about 18%) of the atmospheric CO2 pool is exchanged each year. This large and fast natural CO2 cycling flux is far more than the approximately 6 giga-tonnes of carbon in the anthropogenic fossil fuel CO2 now contributed annually to the atmosphere. On these figures anthropogenic CO2 accounts for just 4.45% of the annual atmospheric turnover – it therefore has only a corresponding 4.45% influence on the 0.12°C mentioned above, at any one time - in other words the effect is negligible.”

One has to wonder why he couldn’t source the data from CDIAC’s ‘Global Carbon Project’.

http://www.globalcarbonproject.org/carbonbudget/08/hl-full.htm

Interestingly, they conclude “The human perturbation of the carbon cycle continues to grow strongly and track near the most carbon intensive scenarios of the UN-Intergovernmental Panel on Climate Change.”

I don’t see this changing – world population is growing strongly, developing countries are developing (sic) and western economies are abandoning responsible growth for unfettered consumerism.

The ‘Carbon Budget’ for 2009 is going to be released in the next week or so. It will be interesting to compare it with this last one.

Well Squeers, as for the edifying exchanges - they've evaporated.
Thank you anyway :)