From the University of Leicester press office: An ancient Earth like ours
Geologists reconstruct the Earth’s climate belts between 460 and 445 million years ago
An international team of scientists including Mark Williams and Jan Zalasiewicz of the Geology Department of the University of Leicester, and led by Dr. Thijs Vandenbroucke, formerly of Leicester and now at the University of Lille 1 (France), has reconstructed the Earth’s climate belts of the late Ordovician Period, between 460 and 445 million years ago.
The findings have been published online in the Proceedings of the National Academy of Sciences of the USA – and show that these ancient climate belts were surprisingly like those of the present.
The researchers state: “The world of the ancient past had been thought by scientists to differ from ours in many respects, including having carbon dioxide levels much higher – over twenty times as high – than those of the present. However, it is very hard to deduce carbon dioxide levels with any accuracy from such ancient rocks, and it was known that there was a paradox, for the late Ordovician was known to include a brief, intense glaciation – something difficult to envisage in a world with high levels of greenhouse gases. “
The team of scientists looked at the global distribution of common, but mysterious fossils called chitinozoans – probably the egg-cases of extinct planktonic animals – before and during this Ordovician glaciation. They found a pattern that revealed the position of ancient climate belts, including such features as the polar front, which separates cold polar waters from more temperate ones at lower latitudes. The position of these climate belts changed as the Earth entered the Ordovician glaciation – but in a pattern very similar to that which happened in oceans much more recently, as they adjusted to the glacial and interglacial phases of our current (and ongoing) Ice Age.
This ‘modern-looking’ pattern suggests that those ancient carbon dioxide levels could not have been as high as previously thought, but were more modest, at about five times current levels (they would have had to be somewhat higher than today’s, because the sun in those far-off times shone less brightly).
“These ancient, but modern-looking oceans emphasise the stability of Earth’s atmosphere and climate through deep time – and show the current man-made rise in greenhouse gas levels to be an even more striking phenomenon than was thought,” the researchers conclude.
Reference: Vandenbroucke, T.R.A., Armstrong, H.A., Williams, M., Paris, F., Zalasiewicz, J.A., Sabbe, K., Nolvak, J., Challands, T.J., Verniers, J. & Servais, T. 2010. Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse. PNAS doi/10.1073/pnas.1003220107.
Contacts: (Mark Williams and Jan Zalasiewicz at the Department of Geology, University of Leicester: Respectively tel. 0116 252 3642 and 0116 2523928, and e-mails mri@le.ac.uk and jaz1@le.ac.uk).
The 600 million year Berner-Scotese composite CO2-Temperature graph is simply understandable by everyone, and should be required reading in every public school.
The Beck 2007 graph depicting CO2 levels between 1820 and 2000, showing CO2 at 425 ppm in 1825 higher than it is today, should also be required reading in public school.
Then there is the teeny weeny Mauna Loa graph showing 52 years of CO2 increasing from 315 to 390 ppm, from 1958 to today. A dot on a graph of geologic time. No, not even a pixel of data on said graph. How pathetic!
“”” RoyFOMR says:
August 10, 2010 at 1:44 pm
Well you can see just by eye; without any computation necessary that the Earth Temperature exactly matches the logarithm (base 2) of the CO2 level; thereby proving Schneider’s Law which is taught to every climate science student in the very first lecture.
Exactly George. The most important part of the course should be left to the end of the course!
Think back to the average state of a first year student, in any neigh all subjects.
Hungover, i’d guess, and thus totally impervious to logical sensitivity.
I vaguely remember my alcohol level 460′ish million years ago. As to the CO2 environment that I co-existed with, forget it. It was all just a blurr! “””
Well I hope that not everybody failed to notice that I had tongue firmly implanted in cheek.
Even with the rather poor scales on those two graphs; there is not the slightest chance that that data fits a straight line plot of earth Temperature versus log base 2 of the CO2 abundance in the atmosphere.
For most of the time; the Temperature is locked at a ceiling of about 22 deg C while the CO2 goes through about five doublings; or is it halvings.
remember that in the modern record since 1957/58 when the Mauna Loa data stream was started we have had about 1/3 of one doubling of CO2; and according to the IPCC the value of the slope of the Temperature Versus Log CO2 graph is uncertain by about 3:1.
Now would some of you mathematical geniuses please tell me how you can distinguish between a linear relationship, and a logarithmic relationship when the slope of the best fitting line is uncertain by a factor of three.
The claim of a logarithmic relationship between CO2 abundance and earth Temperature is just plain silly. Show me any data set where the log relationship is more likely than a simple linear relationship.
Then there is that other problem.
We have (T2 -T 1) = (cs).logbase2(CO2,2/CO2,1) where T2-T1 is evaluated over some climate times scale of say 30 years; while logbase2 (CO2,2/CO2,1) is evaluated over some DIFFERENT time period maybe also of 30 years and the two time periods over which the data is plotted may differ by say +/- 800 years or more; as is evident in the data in Nobel Laureate Al Gore’s pivotal book; where the Temperature changes occur about 800 years before the CO2 changes which cause them.
The whole idea is totally ludicrous.
And remember that the original input FORCING that starts off this logarithmic relationship is the emittance of LWIR from the earth surface; that gets intercepted by the GHG (say CO2); and that surface emittance varies from place to place on earth by more than a factor of 10:1 from the hottest deserts at +60 deg C or more to the coldest reaches of Vostok and surroundings that can be as cold as about -90 deg C; so you have a circular relationship right from the start in that you are trying to detect a small fraction of a degree change in a logarithmic graph with a background Temperature noise of as much as 150 deg C range; and you have to figure out what time differential to have between the Temperature data and the CO2 data.
Well never mind gathering the data; why not just construct a Physics cause and effect model which predicts; excuse me; projects, a logarithmic connection.
Yet climatologists continue to proclaim such a logarithmic relationship when there is neither data; nor theory to support such a connection.
So look at the pretty pink graph above again and see if you can discern where the logarithmic connection is between those two lines. There isn’t any; or any other connection. Something much more powerful than mere CO2 is REGULATING the maximum Temperature that earth can reach through thick and thin for the last 600 million years.
My vote goes to the Physical and Chemical properties of the H2O molecule in all of its three phases.
IT’S THE WATER !
Doing the math:
5000 ppm is 4650 ppm higher than today.
The 100ppm recent rise in C02 is equated by AGW to result in 0.6C rise in global temps.
There are 46.5 100ppm rises between today and 500 million years ago, with each on worth +0.6C
That is 46.5 x 0.6 = +27.9C.
So, today’s global temp of 13C equates to 13+27.9 = 40.9C in the Cambrian. (105.6 F).
Now, that would be a hothouse Earth. But the graph says it was 22c (71.6F).
Both cannot be right. The discrepancy is 21.1C (34 F).
Can we establish a new convention for reference and annotation? Anyone writing a paper or article that has to include a gratuitous AGW sentence in order to satisfy a grant requirements, get the paper past a tenured board, or just to cover your ass in the next round of budget cuts – please annotate this unsupported material with a common reference. I suggest: “as required by convention”
We can trim them out later and not question your underlying work.
“”” Enneagram says:
August 10, 2010 at 11:23 am
George E. Smith says:
August 10, 2010 at 10:46 am ” That will be something to watch; and I plan on staying around to see that historic event”
Could you reveal your forecast for those of us who won’t be here then? “””
My forecast is that the mean global surface Temperature of planet earth will NOT be in excess of +22 deg C in the year 2100 AD.
Some IPCC projections say it could be 10 deg C hotter than today which would put it as much as about 25 deg C. Ain’t gonna happen.
Actually, I could read it quite well, once I saw it….. it doesn’t show up very well in firefox on my monitor – real faint.
And the other questions?
REPLY: Since I did not write the paper, or the university press release citing it above, I’ll refer you to the author contact info is at the bottom of the article, I’m sure they will appreciate your line of questions about their paper. Feel free to report back what they say. – Anthony
Warmists can’t stand it when you bring up past co2 levels. I wonder why? Venus runaway warming tipping point comes to mind and I tell them so.
According to Astrophysical theory, the sun originated with a luminosity of about 70% of the current value about 4.5 billion years ago, and has been increasing in luminosity ever since. In another billion years or so, we’ll have a runaway greenhouse and wind up just like Venus- that’s long before the sun reaches the end of the main sequence in about 5 billion years.
Assuming a constant increase in luminosity, the sun had a luminosity of about
0.7 + (8/9)*.3 = 0.967 about 500 million years ago. Temperature varies roughly as the 4th root of luminosity, so temperatures would have been about
(0.966)^0.25 = 0.991 about 500 million years ago. Antarctica wasn’t covered in
ice yet, so that little albedo change could more than make up for the difference in sunlight.
Hsien-Wang Ou thinks that cloud feedback kept the earth’s temperature relatively stable over the last 4.5 billion years
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282001%29014%3C2976%3APBOTES%3E2.0.CO%3B2
CO2 is to climatology what gravity is to cosmology…greenhouse theory is to climatology what relativity is to cosmology.
they have to couch their paper in these terms to get funding and publishing, ignoring everything else
like the position of the continents. orbital changes. and the sun.
“”” Alan McIntire says:
August 10, 2010 at 4:20 pm
Hsien-Wang Ou thinks that cloud feedback kept the earth’s temperature relatively stable over the last 4.5 billion years “””
No idea who he is; but I’ve been saying that it’s the water for about as long as I have ever heard of global warming; and I didn’t need any fancy thermal models; just the back of an envelope, and some ordinary common sense.
Don’t plan on any runaway greenhouse until you boil off all those oceans; and I am sure we will be long gone well before that time.
What might happen in another billion years is of no help to this Congress, and this administration in deciding on US policy.
One can calculate the solar irradiance at Earth over time with a fairly simple formula:
TSI 440 Mya = 1366 W/m2 * (1-(0.3*440/4550) = 1325 W/m2
(Kastings 2003 is the final word on this and it is not quite a linear change over time but it is close enough).
So, Surface Temp with no extra feedback from CO2 at 4 doublings (and Albedo the same as today) =
Surface Temp 440 Mya = [(1325 *(1-0.3)/4 + 150 + 4*3.7)/5.67e-8] ^.25 = 289.2K or +1.2C higher than today.
There are three estimates of the temperature at the time (+2.0C Berner and Royer 2004), (-4.0C Shaviv and Veizer 2003) and (-3.0C from Scotese).
Now the Albedo was probably higher at the time because glacier covered at least the top half of Africa (which is twice as big as Antarctica) and it could have covered parts of South America as well.
So the CO2 estimates for the period work fine (close to right down the middle) if one assumes there is no secondary +200% feedback from CO2. Hence the need to rewrite the CO2 estimates down to two doubling only.
But there are two compilation estimates of CO2 for the period (4500 ppm Berner 2001) and (5800 ppm Royer 2004 and used in IPCC Ar4) which should not be considered as sceptical sources.
[The findings have been published online in the Proceedings of the National Academy of Sciences of the USA – and show that these ancient climate belts were surprisingly like those of the present.]
The position of the landmasses on the planet have everything to do with the resulting oceanic and atmospheric circulation patterns. The position of the land masses was very different 450Mya:
http://jan.ucc.nau.edu/~rcb7/450_Ord_3globes.jpg
It would be some kind of miracle for the climate belts 450Mya to be like those of the present. I’m throwing the B.S. flag on this claim.
George E Smith,
Nothing snarky about this, honest – just a genuine question. Why do you often use semicolons instead of commas? Or is there a problem with your keyboard? I only mention it because I find it affects the readability of your posts, which is a shame.
Gotcha. Answers aren’t important.
Anyway, my questions were about your graph. Not the paper.
The carboniferous looks pretty problematic for the AGWers, too, doesn’t it?
I can just hear the plaintive response from the watermelon politics crowd:
“But, but, but … That was then, and this is nooowwww!”
:o)
And the late Cretaceous – early Tertiary. An inconvenient truth.
rbateman says:
August 10, 2010 at 3:20 pm
Doing the math:
============================
Nothing like that anti-spin-doctor, “Math” to set the record straight!
@Andrew30 says:
August 10, 2010 at 9:32 am
Thanks for stopping by, Andrew. In a single line, don’t bother to come back, particularly with links to Real Climate . Ta ta!
“groper says:
August 10, 2010 at 9:45 am
460 MYA the earth was probably in a different orbit, continents as we know it didn’t exist.”
And too, as little as 150 years ago, the Atlantic was narrower, the Pacific was wider, Australia was further south, the Moon was closer, albeit not by much in every case, but still, not the same.
Is it my eyes but the chart seems to show 2 stable states, 22 c and 12 c irrespective of CO2 levels? doen anyone know if the cooler times coincide, with some lag with ice ages?
Did anyone else notice the huge drop in temperatures every 150M years, as in NOW, 150MYA, 300MYA, and 450MYA. Is there some cause for this repetitious event?
All of the carbon in the “Fossil Fuels” we burn was CO2 before the Carboniferous.
Infer Ordovician CO2 levels from proxied temperature based on a theoretical model. Use the relationship of the resulting values to support the validity of the model. Rinse and repeat.
GM says at 3:10 pm:
“CO2 is hardly the only thing influencing the climate, there are many many other factors. The point is that none of those other factors has been changing now other than CO2.”
That in a nutshell is the CO2=CAGW conjecture: the climate doesn’t change, and nothing else changes except the CO2 level. Alarmists actually believe that nonsense — while scientific skeptics understand that the climate’s parameters are always constantly changing.
And as usual, GM provides no references like the rest of us do for his wild-eyed speculation.