The dinosaur media are—yet again—reporting the death of climate skeptics because of the latest, greatest paper published by Nature magazine. Increases of dreaded carbon dioxide appear to have preceded the warming that initiated human civilization.
For years, my less-green friends have pointed to the long ice cores in Antarctica, where annual striations go back hundreds of thousands of years. The temperature can be inferred from the relative abundance of common oxygen (16O) and its rarer isotope with two additional neutrons, 18O. In most cases, temperature changes before carbon dioxide does, seemingly inverting the normal cause and effect for the current climate rage.
Not so, say Jeremy Shakun, from Harvard, and his eight colleagues from around the world. They gathered up 80 so-called “proxy” indicators of local temperature (including the Antarctic ice cores), and compared them to the amount of carbon dioxide trapped in the ice. It appears that—after a little non-CO2 temperature rise of speculative origin—carbon dioxide increases indeed preceded the massive deglaciation that began about 20,000 years ago.
Shakun et al. argue that the Antarctic ice cores are a special case, where through a very complicated (and hard to verify) chain of causation, temperature will in fact increase before carbon dioxide.
Enter the internet, one of the greatest things that has ever happened to science. Because of requirement for increased data transparency (pushed, in no small part, by the Climategate gang’s reluctance to release theirs), the numbers behind important papers are now available online.
Go to http://wattsupwiththat.com/ to find the rebuttal to the above.
“It appears that—after a little non-CO2 temperature rise of speculative origin—carbon dioxide increases indeed preceded the massive deglaciation that began about 20,000 years ago.”
First the temperature rises, then the CO2 increases. Finally the ice melts. It takes quite a few years to melt a glacier.
It would appear he agrees with the ‘deniers’; he just doesn’t want to admit it.
Tom,
What I could understand of his technobabble, it was a convoluted mess of adjustments. At best, it indicates that CO2 might possibly have risen before temperatures. However, for the IPCC’s assumptions of CO2 dominance to be correct, CO2 and temperatures would have to increase in geologic lock-step, without any noticeable lag in either direction.
So some ice cores show CO2 rising before temperature and other ice cores show CO2 rising after temperature. You can’t have it both ways.
What this study proves is that paleoclimate data from ice cores are unreliable.
Yes and no klem. It is entirely plausible that you could have hemispheric warming with oceanic degassing showing rising levels in the well-mixed atmosphere prior to warming in the hemisphere where your ice core was extracted.
The global mean temperature rises almost 4K from January to July annually due to the configuration of major land masses, although that is concurrent with a drawdown of atmospheric CO2 levels during the boreal growing season. I don’t think this says the ice cores are unreliable per se, you just have to have more information to use them properly.
The bigger problem Willis Eschenbach uncovered was the truncation of the record where all available ice cores showed CO2 levels continuing to rise as global temperatures fell.
If the temperature *had* to increase (even just a little) to melt the permafrost and release the CO2, then the hypothesis that CO2 is the sole *driver* for a warming climate is blown out of the sky.
It only takes a single counterexample to disprove an unqualified statement.
Unaddressed is the problem of glaciation: what mechanism removes CO2 from the atmosphere in sufficient amounts t0 cause the climate to cool allowing the glaciers to re-form.
Check out Watts Up With That. He does a technical review and finds the data used in the paper doesn’t support the outcome at all. Still can’t tell which came first. Doooh!!! Then he looks at ALL ice core CO2 data (not in the paper) vs. temperature. Turns out the paper cut off the ice core data just before it diverged from the temperature, hiding the divergence. Dooooooooh!!!!
The best book I have read that disproves CO2 involvement in climate change is “Cold Sun” by John L Casey. He proves it is all due to the Sun.
The book is well documented and has support from scientists world wide.
I read this book and it’s junk science. He proves nothing in this book. Although he speaks to many conclusions, he doesn’t provide any basis for his conclusions. Some of his Predictions, i..e, that 2010 will be the coldest year on record, have already been undone by reality. Poorly documented, no citations and the author is neither a scientist and has never published a peer reviewed article.