CO2 concentrations from past years can be accurately determined from the bubbles trapped in the ice. The time resolution is significantly better at the top of an ice core than near the bottom, where some ice flow and compression of the layers occurs. Measuring the pCO2 of a trapped air sample in a bubble is essentially the same procedure as measuring the CO2 content the atmosphere, so to merge the ice core and present-day atmospheric CO2 measurements is a very straightforward procedure. I.e., you just plot the time-series on the same graph.
The time resolution is significantly better at the top of an ice core than near the bottom, where some ice flow and compression of the layers occurs.
Hmmm interesting,
Measuring the pCO2 of a trapped air sample in a bubble is essentially the same procedure as measuring the CO2 content the atmosphere, so to merge the ice core and present-day atmospheric CO2 measurements is a very straightforward procedure. I.e., you just plot the time-series on the same graph.
One should note that temperature leads CO2 concentration in the most recent ice core data the most:
And is totally consistant with the findings of:
Global warming and global dioxide emission and concentration:
a Granger causality analysis
- "We find, in opposition to previous studies, that there is no evidence of Granger causality from global carbon dioxide emission to global surface temperature. Further, we could not find robust empirical evidence for the causal nexus from global carbon dioxide concentration to global surface temperature."
As well as our own inspection of the Paleoclimate record in prior replies that indicates that the long term CO2 temperature correlation is on the close order of 0.27 degree C for doubling of atmospheric CO2 concentrations.
