Saturday, August 30th 2008, 6:02 AM EDT
Proof that anthropogenic CO2 is not accumulating
by Alan Siddons
By current estimates, man is pumping about 4 ppm of CO2 into the air every year. But the atmospheric level is rising only 2 ppm every year. Theory has it, then, that half of human emissions are presently getting absorbed by so-called carbon sinks, thereby cutting the net emission in half every year.
Yet if half of human emissions stay in the air and the other half goes elsewhere, this proves that anthropogenic CO2 is not accumulating — the reason being that absorption is an ongoing process. A 50% reduction factor cannot be applicable only once. The next year would naturally see a further reduction. And so forth.
Simplify the problem to grasp this idea. Assume that from 2000 to 2008 man has been emitting a steady 4 ppm annually, half of which stays in the air. The theory says, therefore, that within this timeframe the atmospheric level will go up a total of 18 ppm, which is consistent with the observed rate of increase. But every year’s emissions must KEEP getting absorbed as time passes. Nothing else makes sense.
A linear reduction rate would be very rapid, erasing a year’s emissions in two years. A logarithmic rate would be more gradual, and it would look like the above chart. That is, 2 ppm in the year 2000 would be reduced to 1 ppm the next year, and so on, gradually diminishing every year. That is, 2 ppm in the year 2000 would be reduced to 1 ppm the next year, and so on, gradually diminishing every year.
Such a continuous annual reduction will have surprising long-term consequences, as the above chart shows.
The level observed in 2008 would be the total of all the previous amounts that remain (in blue). Thus with a yearly emission of 4 ppm from 2000 to 2008 and a 50% reduction rate, the atmosphere would increase by only 4 ppm, not 18. In other words, the accumulation-reduction model is actually self-contradictory. Yes, by imagining a 50% reduction for a single year, the conjecture matches the observed trend: CO2 is seen to rise by 2 ppm annually. But since previous years would necessarily suffer further absorption losses, the result after 8 years would be just a 4 ppm increase — meaning that the yearly observed rate would have to have been around 0.09 ppm per year, not 2 ppm per year!
Notice that you can fiddle with the parameters to get the total accumulation correct, but only by drastically reducing the human estimate plus getting the annually observed increase wrong.
Yearly Emission 2.57
This model is flawed and it can’t be repaired. Proposing a one-time absorption by carbon sinks is absurd. There are several parameters involved in an accumulation/reduction model, parameters that not only have to agree with each other but also agree with reality.
Conclusion: Human emissions cannot explain the rising CO2 trend.