![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.
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  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. |
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“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.
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James Schrumpf says:
September 26, 2013 at 3:56 am
How does the author figure CO2 got so high without human intervention? There is no known natural cycle that increases CO2 and then decreases it again. There are lots of known natural cycles that increase and decrease temperature. Sans human beings, what is the proposed mechanism that creates the Ordovician and Cretaceous CO2 rise, and then fall?
Answer – As the dinosaurs, being partially cold blooded animals who liked to be warm, burnt the forests and the plains to keep themselves warm, the earth got warmer and warmer. They enjoyed the warm planet so much they happily burnt more and more, and used up all the easy to obtain oil (all that stuff that floats on lakes). Because they did not think what they were doing, they burnt all the oil and all the peat, and all the coal that was on the surface. Then, surprisingly, they found it was time for “peak carbon”! No more coal. No more gas. No more oil. And every 14 years 10% of the carbon dioxide gradually leached out of the atmosphere. And as time went on the remaining CO2 kept on going. As the earth got colder and colder, the vegetation grew less and less. And the dinosaurs were feeling the cold and feeling hungry. So being sorrowful for themselves and what they had done to the planet, they just decided to die out.
QED
And who says my reasoning is not as good as that of Mr McLeod?
BTW, David L and others, if we are now at 400 ppm and it is growing at 2 ppm/year, in 100 years it will have added 200 ppm, taking us to 600 ppm, not 200 or 300 years.
It’s possible we will never get to 1,000ppm. Who knows what technologies and efficiencies will be like in the year 2100.Fertility rates around the world have been in decline since I think the 1960s. The world’s population could well start to fall by the middle of the next century or even before that!
I have never heard anyone say there was ice during this period. It’s a strawman paper.
Temps were about 9.0C warmer, sea level was 260 metres higher than today. Most of our oil formed at this time in the extensive shallow seas that covered 35% of the continents.
But there would have been a few glaciers on high mountain summits wherever they existed at the time. There would have been a few left-over from the Pangea formation.
Patrick says:
September 26, 2013 at 4:51 am
So that’s a huge sheet of graph paper equivalent to the size of about 18 x A4 sheets. And only 2 sq. mm’s are man-made CO2. Nice analogy. Thanks.
Like me, I bet you’re pleased they don’t think Nitrogen is the cause of AGW!
Oh deary me. Was this deliberate deception? Any geologist reading this will know instantly that this statement is illogical. Other periods had over 4000ppm with an ice age! Oh deary me.
“Others, such as the EU’s Climate Commissioner, Connie Hedegaard … said: “Let’s say that science, some decades from now, said: ‘We were wrong, it was not about climate’,”
Not even “climate change” now, just “climate”. The movement is retreating into vaquery fast.
And somehow “IPCC scientists” has been depersonalized to just “science”. So in the end, no person or people, including Ms Hedegaard. will ever be wrong, it was all the science’s fault.
I called up science yesterday to ask what it thought of this attribution, and science told my “here’s the data, do your own flippin analysis”.
“GeeJam says:
September 26, 2013 at 5:19 am”
May use lots of paper (Oh no! All that CO2 absorbed by the tree that gave up its life to make paper) but it is easy for anyone to do. Don’t need a PhD, super computer or anything other than some paper with squares on it, a ruler and some crayons (Summat Mann is good at using). So “scatter” those coloured squares evenly over the million other squares…and you get the picture. CO2 “blanket”, really? That picture indicates that those 2 squares which humans are responsible for, in reality, are completely insignificant (In terms of “trapping” heat – LOL).
This may be a bit of off-topic trivia, but I enjoy geology and was intrigued by the poster who noted that the entire Islamic world was under water. For those who are familiar with where oil and gas reserves are found worldwide, it is easy to see that almost all of those places are located in areas that were submerged continental shelves back in the Cretaceous. For example, that shallow sea over what is today Saudi Arabia created beds of very porous limestone that are thousands of feet thick, and that’s where all the oil is. (the shallow sea in North America was similar)
And then it stayed flat and stable for an eon or two, and had a strong cap layer put down on top of the limestone, sealing all of the organic material in and allowing it to cook for an eon or two. Voila, oil and gas! (yes, there’s a bit more to it – I’m not writing a textbook here) Central Europe and Central Asia would have been candidates for large, producing fields, but both areas had their geology fractured by the forces that built the Alps and the Himalaya, respectively – two massive features of our current Earth that are totally absent from the Cretaceous maps, although the proto-Rockies did exist, and the Appalachians of that period may have been similar to the Himalaya of today.
I love maps of the old world, can’t help it. There’s so much to see in them, if you look!
I can now see why Mizzou is a 2nd rate institution of higher education.
How embarassing to the SEC and I am glad they are out of the Big 12!
If this guy is right we are all in trouble.
“wws says:
September 26, 2013 at 6:04 am”
Exactly! So when oil searching geologists find “salt rich” rock, there be oil/gas nearby!
Greg Goodman says:
September 26, 2013 at 2:14 am
really Greg? – as a geologist with 25 years E&P experience and knowledge of the scientific method ,The fact that this was a simple task of bringing up a previously published paper that disproves almost every aspect of this drivel is thought in your narrow-minded definition. Google is an excellent vehicle do this is in an accelerated way, one would say a medium that is now the equivalent of a library. Try again back.
Was there any discussion about ocean currents that could be a significant factor in ice free polar regions?
Ninety million years ago, the American continents were separated, and thus the major oceans of the world were connected in the tropical zone. Three million years ago, that all changed when the Isthmus of Panama formed. Shortly thereafter, the Greenland ice sheet grew more rapidly and the earth descended into a 2.6 million year ice age in which it still remains.. C02 had nothing much to do with it, except when the earth was warmer, C02 levels in the atmosphere raised. This is a natural process, scientifically proven process – C02 follows temperature, and not the other way arournd.
Antarctica’s climate is largely a product of it’s island/continent status as much as it’s location. The southern ocean circumpolar current isolates the continent and homogenizes the water and air temperatures – that is to say, keeps it CCCOOOLLLDDD.
Question: What is a 5F (AGW scare figure) increase in average temperature when it normally averages -50F?
Answer: Twice as cold as 0 degrees C – or one half the radiative output of just frozen water ice. [via Stefan-Boltzmann Law]
….Yeah, we are not melting THAT continent anytime soon.
You won’t have an iceshelf if there’s not a sizable landmass near one of the poles. There have been many periods of the geological past when this was the case.
The drawing shows the same continental shelves that exist, today. The continental shelves are run-off over millions of years. Today’s continental shelves are also the result of coastal flooding. This means there was much less water on Earth in the distant past.
Also, the CO2 concentration was greater when there was less ice. The interpretation should suggest warmer climates cause more life to prosper and hence more carbon to enter the biosphere. Otherwise, the new carbon in the system would have to be inorganic in origin. If nearly all of today’s added carbon is coming from sequestered biomass in the form of coal and oil, where did the extra carbon come from for the dinosaurs?
Sunsettommy says:
September 26, 2013 at 6:34 am
Was there any discussion about ocean currents that could be a significant factor in ice free polar regions?
—————————–
Think of the way ocean currents organize themselves today. For the most part, the Trade Winds at the equator blow east-to-west. This sets up an equatorial current that flows east-to-west until it runs into a continental shelf blocking it. Some of that current will then get directed north along the continental shelf or south along the continental shelf depending on the configuration/angles/depth of the ocean.
Today’s examples are the 3 equatorial currents, the Gulf Stream, the Kuroshio, the Algulhus, the Brazil Malvinus confluence. After getting redirected, these currents will then migrate back around clockwise through the ocean in large-scale gyres.
These larger currents also need about 200 metres of ocean depth to flow properly. They don’t really flow through depths less than this.
Then at higher latitudes, the winds now blow west-to-east and either participate in keeping the water flowing in the clockwise gyres or they form complete encircling currents like the Antarctic Circumpolar current.
Look at the Map at the top of the post. One can easily redraw the world ocean currents at the time, with these simple principles.
I even imagine a warm Gulf-Stream-like current flowing right up through the middle of North America from Texas to Inuvik right into the Arctic ocean (but it might have too shallow for a really strong current). And we do indeed find alligator fossils dating from this time, on both sides of what would have been the North American inland sea all the way up to the Arctic. Giant plesiosaurs are also found.
Another McScientist puts the cart before the horse.
Even AlGore’s idiot disaster movie showed temperature leads CO2, despite his best efforts to pretend otherwise..
I am appalled that ANY geologist could be so lacking in critical thinking as to conclude that just because CO2 and temperatures were higher means that CO2 caused the warm temperatures and that if we reach similar CO2 levels we will have similar temperatures! What’s even worse is that the reviewers and editors of the journal ‘Geology’ apparently were just as bad in not pointing out that not only is such a conclusion illogical, there is abundant evidence that as global temperatures rise, the oceans give up CO2 to the atmosphere. Gore attempted to make the same dumb argument about temperature and CO2 in ice cores but neglected to mention that warming always precedes CO2 in the ice core record. We might cut Gore a little slack because he has no science background at all, but a professional geologist ought to know better.
One of my thoughts is the current position of the continents and their movement is leading to a cooler and cooler global climate. Why? The size of the Pacific basin is getting smaller. This reduces the effect of ENSO warm periods over time. Less and less heat gets transferred to the atmosphere during El Niño cycles. Sure, it will take a long time, but eventually it could lead to a permanent glaciation at higher levels than we’ve seen recently.
In addition, this would also have led to less and less CO2 available for life. Life would be unsustainable on continents and would be limited to oceans. Thank goodness humans are freeing up some sequestered CO2 to help alleviate this problem.
Nope, it was this BBC page that links to Anthony Watts and Andrew Montford
Look in the right comment margin under the heading, “Who are the climate sceptics?”
http://www.bbc.co.uk/news/science-environment-24233643
“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.” Someone please correct me if I am wrong here, but Tanzania, according to the map shown above, is in a moderate zone. So why would we expect a glacial event in this location?
A geologist trying to take the CAGW train late…
Don’t you just love these analyses based upon some little fossil bug, in the wrong part of the world, a world with wildly different unknown parameters of all kinds, for sure different ocean currents given continent positions and who knows if maybe the little bugs were DIFFERENT then. You just can’t make up this kind of stuff. Oh! Never mind.