What was done
The authors present a record of atmospheric carbon dioxide and proxy air temperature data obtained from an ice core drilled at Dome Concordia, Antarctica (Dome C; 75° 06' S, 123° 24' E) for the period between 22,000 and 9,000 years before present, which covers the transition from glacial to interglacial climate conditions.

What was learned
The authors express confidence that their record "is an accurate representation of the atmospheric CO2 concentrations" over the period of study.  With that said, they report the "main feature" of their CO2 record is the 40% increase from a mean value of 189 ppm around 17,000 years ago to a mean value of 265 ppm around 11,000 ago.  Furthermore, close examination of the rise in temperature and atmospheric CO2 concentration at the end of the last glacial maximum (based upon a linear fit of the data) revealed the increase in temperature took place at 17,800 ± 300 years ago, while the increase in CO2 took place at 17,000 ± 200 years ago.  On this basis, the authors conclude that "the start of the CO2 increase thus lagged the start of the [temperature] increase by 800 ± 600 years."

What it means
The results of this paper drive another nail in the coffin of the CO2-induced global warming hypothesis.  As we have reported before (see our CO2-Temperature Correlations Summary and related referenced material), scientific data, such as those of the present study, do not support the notion that CO2 is the all-important driver of climate change that the climate alarmists have made it out to be.  In fact, it appears, like us, to be merely along for the ride.