Fig 4. Except for the well known fact that temperature changes precede CO2 changes,
the supposed CO2-driven raise of temperatures works ok before temperature reaches
max peak. No, the real problems for the CO2-rescue hypothesis appears when temperature
drops again. During almost the entire temperature fall, CO2 only drops slightly.
In fact, CO2 stays in the area of maximum CO2 warming effect. So we have temperatures
falling all the way down even though CO2 concentrations in these concentrations where
supposed to be a very strong upwards driver of temperature. (graph & caption from
Frank Lansner, )
Ice cores refer a core (like an apple core) that usually extends from the surface
to thousands of feet down in ice, either in a glacier or polar ice cap. By analyzing
the CO2 content and an isotope of Oxygen, scientists deduce the temperature and the
CO2 levels at various depths which were deposited over the ages.
When it was found that CO2 and temperature changed together over history, some jumped
to the conclusion that CO2 changes caused temperature changes.
However, as better methods of analysis were developed, it became apparent that the
temperature changed first and only after an average of 800 years did CO2 change.
Since a cause cannot occur before the effect, this proves that CO2 did not cause
the temperature changes.
Next it was claimed that “something unknown” initiated the temperature increase,
then CO2 caused it to continue. The problem here is that, at the peak, the temperature
reverses, while the CO2 remains high. The below graph shows this situation. Read
the whole paper here.Vostok data is here
This is an issue that is often misunderstood in the public sphere and media, so it
is worth spending some time to explain it and clarify it. At least three careful
ice core studies have shown that CO2 starts to rise about 800 years (600_1000 years)
after Antarctic temperature during glacial terminations. These terminations are pronounced
warming periods that mark the ends of the ice ages that happen every 100,000 years
Does this prove that CO2 doesn't cause global warming? The answer is no.
The reason has to do with the fact that the warmings take about 5000 years to be
complete. The lag is only 800 years. All that the lag shows is that CO2 did not cause
the first 800 years of warming, out of the 5000 year trend. The other 4200 years
of warming could in fact have been caused by CO2, as far as we can tell from this
ice core data. (bold added)
(Did you notice the twisted logic to try to pin the blame on CO2? After admitting
CO2 did not start the warming at the end of ice ages, they say CO2 “could” have caused
it to continue! Of course the cause of the original warming could simply have continued.)
1. They admit that CO2 did not cause warming:CO2 starts to rise about 800 years
(600_1000 years) after Antarctic temperature
2. The only other relevant statement is: The other 4200 years of warming could in
fact have been caused by CO2
Notice the qualifier “could have ... been”? That means they can’t prove it, and are
just speculating. Another possibility is that continued warming was caused by whatever
started the initial warming simply continuing. Which is most rational?
Here is what the web site created to support the “hockey stick” said
Peer-Reviewed Papers Show CO2 Lags Temperature Changes
(Science, Vol. 283. no. 5408, pp. 1712 - 1714, 12 March 1999)
- Hubertus Fischer, Martin Wahlen, Jesse Smith, Derek Mastroianni, Bruce Deck
QUOTE: High-resolution records from Antarctic ice cores show that carbon dioxide
concentrations increased by 80 to 100 parts per million by volume 600 ± 400 years
after the warming of the last three deglaciations.
- Nicolas Caillon, Jeffrey P. Severinghaus, Jean Jouzel, Jean-Marc Barnola, Jiancheng
Kang, Volodya Y. Lipenkov
QUOTE: The sequence of events during Termination III suggests that the CO2 increase
lagged Antarctic deglacial warming by 800 ± 200 years and preceded the Northern Hemisphere
Citations from http://wattsupwiththat.com/2014/12/27/vostok-and-the-8000-year-time-lag/
 J. R. Petit*, J. Jouzel†, D. Raynaud*, N. I. Barkov‡, J.-M. Barnola*, I. Basile*,
M. Bender§, J. Chappellaz*, M. Davisk, G. Delaygue†, M. Delmotte*, V. M. Kotlyakov¶,
M. Legrand*, V. Y. Lipenkov‡, C. Lorius*, L. Pe ́ pin*, C. Ritz*, E. Saltzmank &
M. Stievenard† (1999) Climate and atmospheric history of the past 420,000 years from
the Vostok ice core, Antarctica. NATURE | VOL 399 | 3 JUNE 1999 |
Here is a full set of the graphs with links to the actual data
Here is a graph from the National Climate Data center showing CO2 lags temperature
This chart from the National Climate Data center page on CO2 & temperature shows
temperature in blue and CO2 in Red. The accompanying text ignores the fact that the
blue (temperature) plainly changes before the red (CO2). Especially on the downside,
but visible on most increases as a sliver of blue to the left of the red. Click to
see larger at the US government source.