![Cretaceous%20Map[1]](http://wattsupwiththat.files.wordpress.com/2013/09/cretaceous20map1.jpg?quality=83)
From the University of Missouri-Columbia
COLUMBIA, Mo. – For years, scientists have thought that a continental ice sheet formed during the Late Cretaceous Period more than 90 million years ago when the climate was much warmer than it is today. Now, a University of Missouri researcher has found evidence suggesting that no ice sheet formed at this time. This finding could help environmentalists and scientists predict what the earth’s climate will be as carbon dioxide levels continue to rise.
“Currently, carbon dioxide levels are just above 400 parts per million (ppm), up approximately 120 ppm in the last 150 years and rising about 2 ppm each year,” said Ken MacLeod, a professor of geological sciences at MU. “In our study, we found that during the Late Cretaceous Period, when carbon dioxide levels were around 1,000 ppm, there were no continental ice sheets on earth. So, if carbon dioxide levels continue to rise, the earth will be ice-free once the climate comes into balance with the higher levels.”
In his study, MacLeod analyzed the fossilized shells of 90 million-year-old planktic and benthic foraminifera, single-celled organisms about the size of a grain of salt. Measuring the ratios of different isotopes of oxygen and carbon in the fossils gives scientists information about past temperatures and other environmental conditions. The fossils, which were found in Tanzania, showed no evidence of cooling or changes in local water chemistry that would have been expected if a glacial event had occurred during that time period.
 |
||||
 |
 |
|
 |
|
|
 |
  IMAGE: In the study, MacLeod examined fossils of organisms that lived 90 million years ago. This photo is an image from a Scanning electron microscope of a planktic (left) and benthic…Click here for more information. |
|
|
|
 |
|
 |
|
|
||||
“We know that the carbon dioxide (CO2) levels are rising currently and are at the highest they have been in millions of years. We have records of how conditions have changed as CO2 levels have risen from 280 to 400 ppm, but I believe it also is important to know what could happen when those levels reach 600 to 1000 ppm,” MacLeod said. “At the rate that carbon dioxide levels are rising, we will reach 600 ppm around the end of this century. At that level of CO2, will ice sheets on Greenland and Antarctica be stable? If not, how will their melting affect the planet?”
Previously, many scientists have thought that doubling CO2 levels would cause earth’s temperature to increase as much as 3 degrees Celsius, or approximately 6 degrees Fahrenheit. However, the temperatures MacLeod believes existed in Tanzania 90 million years ago are more consistent with predictions that a doubling of CO2 levels would cause the earth’s temperature could rise an average of 6 degrees Celsius, or approximately 11 degrees Fahrenheit.
“While studying the past can help us predict the future, other challenges with modern warming still exist,” MacLeod said. “The Late Cretaceous climate was very warm, but the earth adjusted as changes occurred over millions of years. We’re seeing the same size changes, but they are happening over a couple of hundred years, maybe 10,000 times faster. How that affects the equation is a big and difficult question.”
MacLeod’s study was published in the October issue of the journal Geology.
TomRude is correct.
We should not be too hard on this poor geologist. He probably got a grant for his work and it probably kept Mrs Geologist and the little baby geologists from the poor house
What do you expect out of a University that has the Kenneth L. Lay Chair in Economics?
wws says:
September 26, 2013 at 6:04 am
Thanks for your comments. I too love the paleo map reconstructions. Eyeballed the continental positions vs today’s estimated drift and it did not look too unrealistic. Missed the lack of Appalachain Mtns but noted that the further east portions of the Rockies were not there, as they should not be, since they only grew about 70mm ybp. Did not know there were any Rockies at all 94mm ybp, but then I don’t live that far west and like the Appalachains, had little interest in them. Boxes of rocks, fossils and meteors under my desk from the Big Horn area.
All in all this paper would be funny if it were not so sad.
AlecMM says:
September 26, 2013 at 1:34 am
We are probably dealing with the biggest scientific fraud in History since this paper: 1981_Hansen_etal.pdf (published in ‘Science’)
Para 2; the claim that CO2 blocks IR in the range 7-14 microns (two small bands at ~ 10 microns) is wrong. The correct 15 micron band would only cause 1.2 K surface temperature increase for no change of OLR spectral distribution as [CO2] varies; untrue.
I’m not quite sure why you felt it necessary to bring up this more than 30 year old paper, but since you did you should get it right. Para 2 did not make the claim you assert, rather it said:
“Carbondioxide absorbs in the atmospheric “window” from 7 to 14 micro-meters which transmits thermal radiation emitted by the earth’s surface and lower atmosphere.Increased atmospheric CO2 tends to close this window and cause outgoing radiation to emerge from higher,colder levels, thus warming the surface and lower atmosphere by the so-called greenhouse mechanism(5).”
Which is perfectly correct, further details are given slightly later in the paper:
“Our computations include the weak CO2 bands at 8 to 12um, but the strong 15um CO2 band, which closes one side of the 7 to 20um H20 window, causes [greater than or equal to] 90 percent of the CO2 warming.”
Criticize the paper by all means but do so for what it says not what it does not say.
Phil. says:
September 26, 2013 at 8:37 am
“Criticize the paper by all means but do so for what it says not what it does not say.”
The implication, even if the earth were ice free 94mm ybp, that it was because of CO2 is completely ludicrous given the myriad of other potential causal variables that were different from today, at that time. And that somehow this paper will help us to determine what our world will be like as CO2 rises is laughable and beneath the dignity of a true scientist from any discipline. The obvious play for academic acceptance or grant funds has been pointed out by others on this post.
This study is so bad that it beggars belief. It could only have passed peer review by pals who share the author’s childish faith in the magical power of CO2, or who know how idiotic that belief is, but are in on the gravy train.
Here by contrast is real science, showing that the best explanation for rapid sea level changes observed in the warmest part of the Cretaceous Period (one of the warmest intervals in the entire Phanerozoic Eon) is Antarctic ice sheets:
http://rockbox.rutgers.edu/kgmpdf/03-Miller.Geology.pdf
The Cretaceous is a huge problem for CACA. The only way to make GCMs work in that Period is to assume ridiculously high ECS. CO2 levels were much higher than the 1000 ppm posited in this egregious paper, although might have been that low around 90 Ma. Peak Cretaceous concentration may have been over 4000 & was almost certainly over 2000.
Yet peak warmth occurred about the time of this study, ie 90 Ma, when CO2 was actually falling from its Late Jurassic/Early Cretaceous high. Moreover, the coldest part of the Jurassic & Cretaceous occurred at the Period boundary, when CO2 was at its highest.
The models can’t get the world as warm as it was then without assuming, as noted, preposterously high climate sensitivity. Clearly, other factors are far more important than CO2 levels.
One study which I found convincing attributed Cretaceous warmth & low T gradient polewards to lack of clouds, caused by low biological productivity in the hot tropical oceans. But of course the GCMs don’t do clouds. CACA priests hate clouds.
Sea level was high then, due more to thermal expansion from rapid sea floor spreading volcanism than lack of ice. Yet the evidence strongly suggests that ice somehow managed to form on Antarctica, at least in small, ephemeral fields or sheets, possibly waxing & waning in less than a million years, under Milankovitch orbital mechanical control.
If I had time, I’d like to write up polar dinosaurs & what they show about Mesozoic climate, but maybe another day.
My spidey-sense is tingling, as it always does with fossil isotope studies: Where is the certainty that the little foram skeletons are not somehow altered by just being OLD? Can these operators please assuage this concern? I’m a little dubious that these vaunted ratios could be of any use after taphonomy and diagenesis have had their go at the carbonate rocks surrounding the forams.
The authors are assuming that the only variable is CO2. However a quick look at the map shows that there is another, much more important one.
Wait…he studied forams to come up with this? How did these calcareous shelled critters survive what must have been (per the dogma) highly acidic seas?
Dr. Easterbrook:
Could you submit your comment to “Geology”? I think they need to see dissenting opinion such as yours.
Regards,
Mark H.
Another Geo’s Take says:
September 26, 2013 at 10:05 am
You might enjoy the discussion of Cretaceous coccoliths in the recent “IPCC on Acid” thread.
Seconded. This is ridiculous. Antarctica’s position then, Isthmus of Panama, Ordovician ice age high co2 etc. I am not a geologist but these are the things that immediately came to mind. I’m sure a geologist can do much better than me.
Here is a chart showing Temperatures and all CO2 estimates over the last 750 million years. This Cretaceous period is often described as the “Cretaceous Hothouse”.
http://s4.postimg.org/5nwu2ppdp/Temp_CO2_750_Mya.png
And here are (most of) the estimates of sea level over the last 580 million years.
http://s13.postimg.org/ed3adjh6f/Paleo_Sea_Level_580_Mya.png
Prior to the EAGW mania peer reviewed papers supported the assertion that there was a lack of correlation of atmospheric CO2 and past ice epochs. Recently the EAGW paradigm pushers have been revising geological science to attempt to make the observations fit the EAGW paradigm.
Inappropriate modification and revisions of proxy data and analysis, to fit a hypothesis is a common problem in all fields of science. The revisions in the case of CO2 Vs Temperature is challenging as there are sets of observations that show a lack of correlation of levels atmospheric CO2 and planetary. (Wack a mole problem.)
Prior to the revisions there was agreement that there were four ice epochs (cold periods, we are living in an interglacial period of the fourth ice epoch).
http://mysite.science.uottawa.ca/idclark/courses/Veizer%20Nature%202001.pdf
“Evidence for decoupling of atmospheric CO2 and global climate during the Phanerozoic eon
But our data conflict with a temperature reconstruction using an energy balance model that is forced by reconstructed atmospheric carbon dioxide concentrations18. The results can be reconciled if atmospheric carbon dioxide concentrations were not the principal driver of climate variability on geological timescales for at least one-third of the Phanerozoic eon, or if the reconstructed carbon dioxide concentrations are not reliable.”
The alternative mechanism as to what causes the ice epochs is increased GCR (galactic cosmic rays which is the confusing term that is used for the mostly high speed protons which create cloud forming ions in the atmosphere) which occurs when the solar system passes through the plane of our galaxy.
http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/Phanerozoic.pdf
Celestial driver of Phanerozoic climate?
http://www.eike-klima-energie.eu/uploads/media/Shaviv.pdf
On climate response to changes in the cosmic ray flux and radiative budget
William:
Real time observations (planetary temperature change over the next few years) will resolve the question is CO2 the primary driver of planetary climate or is cloud modulation by solar magnetic cycle changes and long term GCR changes the primary driver: 1) Unequivocal cooling (caused by increased cloud cover not due to TSI changes) caused by increased GCR, caused by the solar magnetic cycle 24 slowdown, 2) the resumption of significant warming, or 3) lukewarm warming , will settle which hypothesis is or is not correct.
Reblogged this on Public Secrets and commented:
The author of the study makes an intellectual error by implying that rising CO2 levels caused an ice-free Earth; correlation, after all, is not necessarily causation — did the CO2 rise precede or follow the ice-free state, or were they both effects of another cause (solar cycles, for example)? Still, the basic research is interesting and the map of Cretaceous Earth is neat.
THESE KND OF ARTICLES WHICH ARE RIDICULOUS SHOULD NOT BE PRESENTED OVER THIS WEB-SITE.
THIS WEB-SITE IS TO GOOD FOR THIS KIND OF GARBAGE.
What they purposely leave out is during the late ORDOVICIAN PERIOD , CO2 levels were around 4000 ppm , and the earth experienced an iceage.
A more likley reason why the CRETACEOUS PERIOD was ice free was due to the land/ocean geographical arrangements which were arranged in a way which would not promote the formation of icecaps.
Unlike today’s arangement which is much more liely to produce icecaps.
This article is ridiculous.
Phineas Fahrquar says:
September 26, 2013 at 11:46 am
CO2 was much higher than now during the LK, but its concentration was falling, not rising. It had been even higher at the LJ/EK boundary.
Must have been all those factories and fossil fuel burning that caused the increase in CO2 that caused the temperature to be so high. Then “man” became extinct…then started all over again some 4 million years ago.
Do I need the sarc?
The absence of several mountain ranges should be a mention as without the Himalayas lots of warm tropical air would flow north moderating the now Asian continent. Same for the Alps.
The level of CO2 in the atmosphere was 4000 ppm at height of last glaciation end of story. Carbon has nothing to do with warming.
“In our study, we found that during the Late Cretaceous Period, when carbon dioxide levels were around 1,000 ppm, there were no continental ice sheets on earth. So, if carbon dioxide levels continue to rise, the earth will be ice-free once the climate comes into balance with the higher levels.”
The monstrous idiocy of this paper is concentrated in the single word “so”. How can any serious student of palaeohistory glibly assume that the relationship between CO2 and temperature is so rigidly linear that one can simply read off temperature from CO2 and CO2 from temperature.
The real relationship between palaeo temperatures and CO2 levels in air is shown in this figure:
http://imageshack.us/photo/my-images/34/7ty.png/
The “so” in this paper is
SO non-sequitur
SO shallow
SO fatuous
SO banale
SO ignorant
SO mendacious
SO lazy
SO dishonest
SO complacent
SO plain wrong
SO AGW
David Gladstone says:
September 26, 2013 at 1:38 pm
Carbon dioxide in the air might even have been higher than that during the Ordovician glaciation, but that wasn’t the last one. During the longer Carboniferous/Permian glaciation, CO2 concentrations were similar to now, although higher than during Pleistocene glacial phases, as we’re in an interglacial. However, during the Jurassic/Cretaceous cold phase, which might have produced a full-on glaciation were the continents placed differently or had there been less sea floor volcanism, CO2 levels were much higher than now, but probably lower than during the Ordovician.
Our present Cenozoic glaciation began when CO2 was higher than now. There is little to no correlation between CO2 & glaciations, except that prolonged cold will tend to pull atmospheric levels down into the oceans (gas that is, not heat). It’s more an effect than a cause.
I like this YouTube video of tectonic palaeo-history of the phanerozoic:
A nice description of continental tectonic history is also given at:
http://www.burkemuseum.org/static/geo_history_wa/Dance%20of%20the%20Giant%20Continents.htm
I’m a Pangea denier too.