Thank God, we have lawyers to defend us from the evil agenda driven government dependent scientists, scientists whose sole aim is not finding truth, but winning grants and who are willing to fudge, lie and destroy human civilization as we know it as long as they can get grants.

cohenite, seems to me that you want readers to believe that you understand Knorr's work better than Knorr.

How likely is that?

And given that Knorr had answered one, small question you put to him, why didn't you then put your controversial conclusion to him for comment

Part 1.

Knorr's paper shows the AF has not changed over the period of study; this contradicts Canadell and other studies showing it increasing.

The AF is the amount of human emitted CO2, ACO2, left in the atmosphere after that amount of ACO2 is areabsorbed by sinks.

ACO2 is calculated using fossil fuel burning, cement manufacture and land use change, LUC. Canadell finds LUC to have been a constant 1.5Gt/yr since 1959. Intuitively this would appear to be problematic. Tom Quirk notes ice core records from the 1950'2 onwards suggest LUC has been a net absorber.

Knorr calculates the AF by combining all emissions, natural and ACO2, detrending for ENSO and volcanoes to produce the remainder which is made up of ACO2, the AF and then comparing that to all ACO2 emissions. Inherent in this, apart from the assumption of a constant LUC amount [although Knorr does query this], is the assumption that natural CO2 emissions and sinks are in balance. Dr Knorr confirms this in his communication with SfB when he says:

"if 40-50% of man-made emissions stay in the atmosphere after account for the balance of the natural fluxes,"

The article has gone to some effort to throw doubt on that key assumption of a balance between natural CO2 emissions and sinks.

If that assumption of balance is wrong then doubt is cast on the calculation of the AF. If the assumption is right then interannual variation of the AF is moot because if the natural factors are removed from the equation than the AF must be a constant ~40% of the total ACO2 emissions which has increased over the period; that would mean the AF would vary from year to year while remaining a fixed %.

Part 2.

It is this point which seems to have confused SfB who has accused me of saying the AF applies to "the atmosphere overall", I haven't, and assuming in real terms the AF is fixed, which I also haven't.

If he means I have said the 40% AF must occur every year instead of being an average over the whole period for that to happen would mean the AF is calculated by reference to ALL CO2 emissions not just ACO2.

I have not misrepresented Knorr which as I say is about the disproof of the idea from Canadell andothers that the AF is increasing.

The interpretation that the constant AF [along with other factors, primarily the lack of balance which the AGW supporters have not referred] means ACO2 cannot explain all the atmospheric increase is the article's point; not Dr Knorr's

To sum up the real situation

Scientists want to know if the earth's systems can continue to suck up CO2 at the present or will our emissions start to overwhelm natures ability to absorb CO2.
One group lead by Knorr says well it has not so far, another group says it has started to do so recently.

The way scientists attempt to answer this question is to add up all the anthropogenic Co2 emissions and then compare it to the measured increase of CO2 in the atmosphere. The result when averaged over decades is that very roughly 40% (+or-14%) remains in the atmosphere. This is referred to as the Airborne Fraction. If AF increases the interpretation is that nature ability to absorb anthropogenic CO2 has declined thus compounding the excess CO2 problem. Cohenite's interpretation is that natural Co2 emissions, must in that case, have increased, which does not advance his case as the most likely explanation is that higher temperatures are the cause which comes back to climate change and is a predicted feedback

warmair, the effect of extra CO2 being emitted due to AGW warming and thereby amplifying the initial AGW warming is much smaller than AGW theory relies on; see Franks:

http://www.nature.com/nature/journal/v463/n7280/full/nature08769.html

Anyway, that is beside the point; there has been no warming for 16 years and the warming over the 20thC was due to solar.