Skyhunter said:
The samplings are not indicative of global atmospheric CO2. I do find them interesting, but not particularly relevant the debate about AGW.
Why not? So which sampling is? What is the selection standard. And how objective would that criterium be. It's not like the inverse proportionality between the attractiveness of the facts and the acceptance standards, is it? If facts are unattractive we refuse to accept them.
Old and somewhat questionable science is not sufficient evidence to refute AGW.
Since when is there a "best before..." date, or should studies also include a sentence: "these data are only valid until Nov 2th 2006?" if you want to question the science, you read the papers, reproduce the methods that were used and calibrate the results with modern methods. And remember, they were first, so the onus of falsifying their results is with the challenger.
I wonder what results will be there for the reproduction of those studies that produced low CO
2 measements consisently. I read that some used sulpher acid to dry out the air. I wonder what that does to the CO
2 contents of the air.
From what is now known about atmospheric CO2 physics, such erratic fluxes are not possible.
No that's a circular reasoning, we observe flat CO
2 rates in the ice cores, rejecting data that show much higher rates, so we conclude that CO
2 rates of changes cannot be big and we compute a resident time of 100 years for CO
2 empirically, based on our selective data. In reality the annual balanced exchange rate between oceans and atmosphere are in the order of magnitude of 100 GTC. Change something in that balance and the accumulation rate of CO
2 in the atmosphere may be surprising. Actually there are several of that kind of CO
2 spikes in the past recorded in fossil leaf stomata proxies.
If such fluxes occur and can be observed in the future, without leaving other proxy evidence, then these samplings will add a new dimension to our understanding of the carbon cycle.
We can anticipate that by returning to the scientific method and accept sound observations that do not fit our world view, even if it refutes the misunderstandings about the greenhouse gas mechanism.
Until such time it is right to attribute these readings to regional anomalies or sampling errors.
How many samples are required and how many regions to realize that there is more to it?
Now why would they not?
If the CO2 concentration was at 430 ppm for a decade, it would increase the concentrations in the lower firn (80-100 meters). So the ice that formed at these depths in the 1930's and 40's would register a higher concentration of CO2.
Well, there was an issue with CO
2 in firn and ambient temperatures. Since the Greenland Ice cores did show strange spikes and consistent CO
2 values of over 300ppmv in contrast with the Dome C, Vostok Antarctic proxies, it was declared void, probably contamination, chemical reactions and extramorphes, bacterea algea, etc due to the higher temperatures (ca -33C) compared to the Antarctic domes (-45-60C). But the firn closure rate of those is far to low (mm to cm per year) to register any spike. So we found a high accumulation core in West Antarctica, Siple Dome with meters per year, which shows a neat CO
2 proxy fitting exactly to our perceptions...
However the firn temperature of ftp://sidads.colorado.edu/pub/DATASETS/AGDC/nsi0098_severinghaus/firn_temps.txt is much higher than Greenland. So, how is that for selective acceptance standards? How about accepting both Greenland and Siple Dome, and we have a problem to solve; or neither Greenland and Siple Dome, and we have no data anymore? The latter is probably more correct. As Severinghaus et al has figured out something out about al kind of fractionation processes going on in the firn, we have probably seen only the beginning. For instance, how about thermal and molecular fractination of CO
2 in relation to O
2 and N
2 in the diffusion processes between firn and the atmosphere?
The advantage of not being steered by the AGW paradigm is that you can wonder freely about surprises in nature, instead of ignoring them or declaring them void. But I agree that the 1935-1945 CO
2 spike should be visible in more proxies. We’re working at d13C in tree rings currently and perhaps we can find some high resolution coral of that time