"Yes, there is. It has our signature ..."
Not really. I am familiar with this website of environmental extremists. They cannot withstand any criticism. The whole argument about isotope compositions is highly speculative, as many (if not all) other arguments. First, I have never seen any error analysis of this kind of calculations. 13C is 1% of 12C. They are talking about 0.03%, 0.15% changes of a 1%, so it is 3-15 ppm differences, which they call "quite different isotopic composition". I think they are using mass-spectrometers to determine the ratio, but I find it highly improbable that accuracy in peak amplitude distinction is good enough to detect 0.03% in close isotope peaks. There must be a vast statistics of different samples, but I haven't seen any raw data ever reported to verify the accuracy of conclusions.
Second, the total yearly man-made infusion of CO2 is about 2-3% of the total global carbon turnaround, which diminishes our influence on 13C concentration to about 1-2 atoms per million at most. I am sure there must be analytical difficulties in honest detection of such small trends. The 2-3% number is for today. How much it was in 1850, so it allegedly caused the so "dramatic decline" in 13C/12C composition?
Third, they are talking about "average 13C/12C ratio of the atmosphere". I'd like to see an analysis of assumptions that leads from isolated stations (usually located near volcanoes) to estimates of global averages.
Tree ring science reminds me of tea leaves techniques...
Cheers,
- Ali |
