Crowdsourcing the WUWT Paleoclimate Reference Page – Continued

Mike McMillan says:
March 30, 2013 at 10:56 pm
I’ve reduced the 110,000 yr “gisp2temperature.png” source image to 8-bit color, so it should be easier to display and download. Annotated as “after:
Who made that image?
————–
I did.
It is based on how the dO18 isotopes actually vary with temperature at the Greenland Summit. There is an actual measured formula which is consistent with how these isotopes typically change with temperature, altitude, proximity to the poles and proximity to the oceans in all other locations around the world and with the internationally recognized VSMOW-world standard.
The other GISP2 temperature charts have recalibrated the exact same dO18 isotope data but this time based on borehole thermometry models. It is theoritical and faulty in my opinion.
Or one could look at it another way. The Antarctica isotopes vary by almost exactly the same amount as Greenland in the ice ages. But the Antarctic temperature changes are only -10.0C at the last glacial maximum (as in polar amplification) while the Greenland borehole calibrated temperature change is -25.0C (as in polar amplification gone wild). The north Atlantic temperature estimates are about -4.0C at the last glacial maximum while 500 kms away at the summit, it is -25.0C?
In addition, now that the ice cores have been extended back to the beginning of the Eemian interglacial, (NEEM just published) we see that Greenland got to +8.0C in the Eemian at 128,000 years ago based on the borehole methodology and much more of the glacial ice should have melted at these temps. Its just not accurate.
The Antarctic ice core scientists (and there alot more of them) have not fallen for the borehole models and use the real dO18 isotope temperature conversion formula. The Greenland ice core scientists lead by Cuffey, Clow, Dahl-Jensen and Alley have distorted the actual temperature changes.
You can remove the two charts labelled “GISP2 temperatures from dO18 isotopes” if you want to stick with the typically used GISP2 borehole-calibrated temperatures. But maybe one might want to see another probably more accurate view.

The third graph from BioCab seems to be wrong for its CO2 scale at the right: starting at 210 ppmv, which is too low for the Holocene (270-280 ppmv at minimum).
cementafriend says:
March 30, 2013 at 5:28 pm
and
justthefactswuwt says:
March 30, 2013 at 7:06 pm
While I do admire the tremendous amount of work that the late Ernst Beck has done, his compilation has little to do with the real “background” CO2 levels of that time. Think about that: a peak around 1942 of 80 ppmv in a decade or so up and in a decade down. That is equivalent to burning down and regrowth of 30% of all land vegetation on earth… Even if the oceans may release such an amount in short time (be it not from temperature changes, but from external acidification), there is no sink on earth that can capture that amount in only a decade…
Moreover, not any other direct measurements in ice cores or proxies like coralline sponges or the – by some – much beloved stomata index data show such a huge change around 1942. Here the stomata data calibration against ice cores / firn / direct measurements over the past century:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/stomata.jpg
The 1942 CO2 data officially were around 320 ppmv (ice cores). If the real data were at 380 ppmv, then the stomata index datapoints should be near the bottom of the chart.
Further the Kaplan chart shows a change of 0.2°C. According to Henry’s Law, that is good for a maximum increase in seawater CO2 pressure of 3 microatm. That is fully compensated by an increase of ~3 ppmv CO2 in the atmosphere.
See further:
http://www.ferdinand-engelbeen.be/klimaat/beck_data.html
There has to be real doubt that proxy data from ice-cores which show less than 280pmm are correct.
Let the late Jaworowski rest in peace, together with his opinions about ice cores. What he wrote after many of the initial drillings in ice cores might have been true in part, but most of his objections were already refuted by the work of Etheridge e.a. in 1996. That was by drilling 3 ice cores at Law Dome with a high accumulation rate with three different drilling techniques (wet and dry), measuring CO2 levels top down in firn and ice, etc… See:
http://onlinelibrary.wiley.com/doi/10.1029/95JD03410/abstract
unfortunately, the full article is behind a paywall.
If any values below 280 ppmv are unreliable, can anybody show me how CO2 measurements of the ice core air (after over 99% sublimation and cryogenic separation) can be as low as 180 ppmv, while the outside air in the atmosphere is near 400 ppmv and beyond (in the lab…)? See further:
http://www.ferdinand-engelbeen.be/klimaat/jaworowski.html

A true skeptic will always ask, “What if I’m wrong and they’re right?”
Obviously this question would never occur to a warmist.
Not enough skeptics ask themselves this question. People, we’re skeptics because we’re saying, “Extraordinary claims require extraordinary proof. Prove it then I’ll believe it.”
We’re not skeptics because we have an alternative belief, which is equally subject to being falsified.
Only if you’re truly brilliant and a Richard Feynman or Albert Einstein will you ask, “What if I’m wrong and everybody else is also wrong?”

I don’t think one can reliably use sea level to calibrate ice volume (especially over the last 100 million years). (maybe the last 5 million years but not over the last 100 million years).
The problem is that sea level has been falling for (almost) that entire period as the Atlantic Ocean has formed and has deepened and widened.
It started out as a simple Rift Valley (with lots of volcanoes) about 200 million years ago as North America split from Pangea, with Europe in tow. One day, the ocean invades the rift and we have a Persian Gulf or a Red Sea rift sea. If the rift continues widening, then the depth slowly increases as the ocean sinks in the mantle (it really does). But it can take 50 million years to 100 million years for one of these new oceans to reach a mature ocean depth of 5000 metres.
As the Atlantic really opened up, with South America splitting off and then Europe from North America (60 million years ago), the average depth of all the oceans on the planet was lower. The ocean had nowhere to go except onto the land.
A shallow ocean covered North America from Texas to Inuvik to Hudson Bay. Europe and the Middle East were nearly completely flooded. Sea level was probably 265 metres higher 94 million years ago.
It would be impossible to infer ice volume and glacial ice from sea level in that situation. In fact, there probably was no ice because all that warm shallow ocean covered so much of the planet. One could even imagine a nice warm current flowing up from the then Gulf of Mexico through Texas to the Arctic ocean. Indeed, crocodiles have been found in Alaska dating from this sea level high stand.
The estimates in the Cramer paper are probably just another attempt to jack up the CO2 sensitivity estimates from the paleoclimate by playing around with sea level/ice volume correlations.

GISP2 actually has some ice in it that has been dated at 250,000 years ago. There is just so much distortion at the bottom of this particular core at bedrock that people don’t feel confident in using the oldest data. Its not easy to find all the data which has been used.
The NGRIP ice core has less distortion at the bottom (and matches GISP2 very closely over the whole period) so it has generally been used the most recently. It has been carefully extended back to 122,750 years ago. On this page.
http://www.iceandclimate.nbi.ku.dk/data/
The new NEEM ice core extends the confirmed Greenland data back to 128,000 years ago, into the Eemian interglacial. Data here.
http://www.nature.com/nature/journal/v493/n7433/full/nature11789.html#supplementary-information
So here is a chart showing NGRIP-extended, NEEM, Epica DomeC Antarctica and the estimated Global temperature going back 135,000 years ago.
Could probably add this chart to the Reference page.
http://s12.postimg.org/9ctilkusd/NGRIP_NEEM_EDC_Global_135kya.png