How hot did Earth get in the past? Scientists uncover new information
The question seems simple enough: What happens to the Earth's temperature when atmospheric carbon dioxide levels increase? The answer is elusive. However, clues are hidden in the fossil record. A new study by researchers from Syracuse and Yale universities provides a much clearer picture of the Earth's temperature approximately 50 million years ago when CO2 concentrations were higher than today. The results may shed light on what to expect in the future if CO2 levels keep rising.
The study, which for the first time compared multiple geochemical and temperature proxies to determine mean annual and seasonal temperatures, is published online in the journal Geology, the premier publication of the Geological Society of America, and is forthcoming in print Aug. 1.
SU Alumnus Caitlin Keating-Bitonti '09 is the corresponding author of the study. She conducted the research as an undergraduate student under the guidance of Linda Ivany, associate professor of earth sciences, and Scott Samson, professor of earth sciences, both in Syracuse University's College of Arts and Sciences. Early results led the team to bring in Hagit Affek, assistant professor of geology and geophysics at Yale University, and Yale Ph.D. candidate Peter Douglas for collaborative study. The National Science Foundation and the American Chemical Society funded the research.
"The early Eocene Epoch (50 million years ago) was about as warm as the Earth has been over the past 65 million years, since the extinction of the dinosaurs," Ivany says. "There were crocodiles above the Arctic Circle and palm trees in Alaska. The questions we are trying to answer are how much warmer was it at different latitudes and how can that information be used to project future temperatures based on what we know about CO2 levels?"
Previous studies have suggested that the polar regions (high-latitude areas) during the Eocene were very hotgreater than 30 degrees centigrade (86 degrees Fahrenheit). However, because the sun's rays are strongest at the Earth's equator, tropical and subtropical areas (lower latitude) will always be at least as warm as polar areas, if not hotter. Until now, temperature data for subtropical regions were limited.
The SU and Yale research team found that average Eocene water temperature along the subtropical U.S. Gulf Coast hovered around 27 degrees centigrade (80 degrees Fahrenheit), slightly cooler than earlier studies predicted. Modern temperatures in the study area average 75 degrees Fahrenheit. Additionally, the scientists discovered that, during the Eocene, temperatures in the study area did not change more than 3 to 5 degrees centigrade across seasons, whereas today, the area's seasonal temperatures fluctuate by 12 degrees centigrade. The new results indicate that the polar and sub-polar regions, while still very warm, could not have been quite as hot as previously suggested.
The findings are based on a chemical analysis of the growth rings of the shells of fossilized bivalve mollusks and on the organic materials trapped in the sediment packed inside the shells, which was conducted by Keating-Bitonti and her colleagues. Ivany collected the fossils from sediment layers exposed along the Tombigbee River in Alabama. The mollusks lived in a near-shore marine environment during a time when the sea level was higher and the ocean flooded much of southern Alabama. The sediments that accumulated there contain one of the richest and best-preserved fossil records in the country.
"Our study shows that previous estimates of temperatures during the early Eocene were likely overestimated, especially at higher latitudes near the poles," Keating-Bitonti says. "The study does not mean elevated atmospheric CO2 levels did not produce a greenhouse effectthe Earth was clearly hotter during the early Eocene. Our results support predictions that increasing levels of atmospheric CO2 will result in a warmer climate with less seasonality across the globe."
To determine the average seasonal temperatures in the study area, Keating-Bitonti sampled the mollusk shells for high-resolution oxygen and strontium isotope analyses, which were done at SU. The Yale team analyzed shells and sediments for clumped-isotope and tetraether-lipid analysis. The results were consistent across all of the independent analytic methods. The scientists believe the multiple methods of analysis have yielded a more complete and accurate picture of ancient climate than previously possible.
The study also marks the first time clumped-isotope analysis has been used alongside traditional oxygen isotope and organic geochemical analyses in paleoclimate work. The research team is currently using the same analytical process to determine Eocene Epoch mean annual and seasonal temperatures in polar-regions.
"Clumped isotopes is a new way to measure past temperatures that offers a distinct advantage over other approaches because the technique requires fewer assumptions; it's based on well understood physics," Affek says. "The agreement among different methods gives us confidence in the results and enables us to use these methods in other locations, such as Antarctica."
Provided by Syracuse University
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Jul 05, 2011
Rank: 1.5 / 5 (17)
lol, yeah, so why did they get it backwards? This time around is opposite of the past, so an analogy with past warming is invalid. The cause was obviously not the same, according to AGW theory. Do I really need to read the rest of this story?
If the results are consistent with the above results then it will be interesting, but the usefullness of comparing those results to current warming are extremely limited. The shape of continents and oceans was quite different then. It would take a lot of work to show how systems today might respond in the same way as the systems back then did.
Jul 05, 2011
Rank: 3.7 / 5 (6)
Natch.
Jul 06, 2011
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Jul 06, 2011
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Jul 06, 2011
Rank: 4.4 / 5 (20)
What's absurd it your clinical stupidity.
Jul 06, 2011
Rank: 4.7 / 5 (13)
However, using this same logic, their deity could equally have been a bit mischievous and finished creating the universe just yesterday with everything ready-made and in place including our memories, books (e.g. the biblical texts), and everything else in the universe all cunningly contrived to make it appear to have been created 6K years ago.
In fact, why stop at yesterday? Why not have creation completed just a minute ago, or just a fraction of a second ago? After all, this omnipotent god would only need to implant all the self-consistent life-memories right up to the present in everyones minds. This surely reveals the patent absurdity and the anthropocentric fallacy of having some deity create everything ready-made just a few thousand years ago!
Jul 06, 2011
Rank: 4.7 / 5 (13)
Jul 06, 2011
Rank: 4.6 / 5 (9)
Jul 06, 2011
Rank: 3.8 / 5 (9)
Jul 07, 2011
Rank: 4 / 5 (1)
Jul 07, 2011
Rank: not rated yet
"...or just a fraction of a second ago?"
lol
To give us something to do, we must first solve Plancks' constrictions. Given time, we will pinpoint exactly at what point we were led astray.
lol
Jul 07, 2011
Rank: 1 / 5 (2)
But, given time as measured by whom?
Jul 08, 2011
Rank: not rated yet
A figure of speech, of language. Given...ah, whatever.
Cosmology asserts a point (in space?) where 'time' (and/or an 'observer'?) had not yet 'entered' into the 'events'.
Dimensionless 'quantities' appear all 'time'. lol.
Not sure if 'measurement' is assessable for 'dimensionless quantities/numeric values'
Words like 'uncertainty, probability, potentiality', are still 'richer' than a kevinrtrsian worldview.
Jul 08, 2011
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In the world of infinities, 'relationships' are the 'tools' of description. No need for 'physical' description.
For kevinrtrts, God is an infinity.
There is nothing we know of that is not irreversible.
(Nothing is truely 'lost' - belief in laws of conservation)
We are surprise that the finite creates infinities.
(People inventing Gods or the infinite.)
Sorry for the digression.
Tracing past climate is tracing back infinite paths that have conditions that are the most consistent to science today.
Jul 08, 2011
Rank: 3.4 / 5 (5)
Jul 08, 2011
Rank: 5 / 5 (1)
Kevin's God is not subject to Kevin's will.
God forbid! :P
Jul 09, 2011
Rank: 1 / 5 (3)
No. There certainly are a few people who believe such nonsense just as there are a few people who believe the earth is flat.
Most people (including those of us who believe God created the universe) do not hold such foolish beliefs.
Accusing a large group of people of believing the foolishness of a few is disingenuous.
And this article is not about religion ...
Jul 09, 2011
Rank: 5 / 5 (2)
I'd hesitate to describe the Creationists as being few in numbers.
Tell that to the Creationists who continue to show up here.
Jul 09, 2011
Rank: 1.4 / 5 (5)
I did not say or imply that people who believe in Creation are few in number. I said that people who believe the nonsense that the earth is 6,000 (7,000; 10,000; etc.) years old are few. There are a few people who will believe anything -- such as the flat earth society. But there are few who believe the earth is flat and there are few people who believe the earth is a few thousand years old.
Again, it is disingenuous to label a large group of people with the nonsense of a few foolish people.
You can certainly say you do not like God. You can even say you don't believe in him (regardless of your actual belief), but calling people who believe in him idiots is childish and unproductive.
You shouldn't do that.
Jul 09, 2011
Rank: 1.5 / 5 (8)
The question today is CO2 a lagging or leading indicator.
Temporal resolution can be quite good today.
Does the data show what happened 50M 1 years ago, 50M 2, ...?
Jul 09, 2011
Rank: 5 / 5 (2)
I said nothing of the sort.
As for the bulk of today's Creationists, these are Bibilical literalists, properly described as Young Earth Creationists.
Jul 09, 2011
Rank: 1 / 5 (4)
Directly after saying you said nothing of the sort, you said it again.
You lie when you say that. It is just not true. Most people who believe the bible are not "Young Earth Creationists".
I, for example, believe the bible. I believe God created the universe. I do not believe in a "Young Earth".
I know many people who believe in Creation. I have never met a Young Earth Creationist and I wager you have not either. I have never met a Flat Earther either and probably never will. It is unlikely any of us will ever meet members of such a small group of foolish people.
Jul 10, 2011
Rank: 5 / 5 (4)
Kevin is a Young Earth Creationist, as are most Creationists.
Please research the matter so as to avoid making further false accusations. Review Old Earth Creationism, Young Earth Creationism, and their variants.
Jul 10, 2011
Rank: 1 / 5 (6)
Why don't you research the matter so you will stop making false accusations.
I will continue to point out your false statements.
BTW, have you ever actually met a Young Earth Creationist?
Have you ever actually met a Flat Earther?
Have you ever actually met someone who has been examined by UFO occupants?
I'll wager you have met many people who believe the universe was created though you have probably not met a single individual who is a young earth creationist.
Believing that the Universe was created does not equate with the foolish notion that the earth is a few thousand years old.
You should stop saying what is obviously not true.
Jul 10, 2011
Rank: 5 / 5 (3)
And, yes, I have researched the matter.
And, yes, I do personally know Creationists.
And, yes, they are Young Earth Creationists.
Creationism is not about what you seem to think it is. And, unless and until you are able to put aside your preconceived notions, you'll never learn that fact.
And, yes, you should stop saying what is patently false.
Jul 10, 2011
Rank: 5 / 5 (3)
http://www.earthm...-7db-6-a
Jul 10, 2011
Rank: 5 / 5 (3)
http://www.earthmagazine.org/
Jul 10, 2011
Rank: 5 / 5 (3)
Jul 10, 2011
Rank: not rated yet
http://www.physor...ogy.html
Jul 10, 2011
Rank: 2.8 / 5 (4)
Jul 11, 2011
Rank: 1.6 / 5 (7)
No more macro-evolution, that is for sure, and the presumptuous age of the earth and the froward history of its climate is definately out the pane frame!
However, significant figures are, unfortunately, rarely discussed outside of an honest classroom these days: the stink of socialism attempts to subvert the sweet savor of truth.
Jul 11, 2011
Rank: 1 / 5 (2)
Dear dear Peter, you seem to think that such a strawman makes your argument so creative. No creationist even suggests everything was ready made. That would be ludicrous, considering they would believe they were born through reproduction and obviously aren't Adam or Eve.
What a Creationist believes, whether OEC or YEC, is that God is the source of initial matter and the physical laws. Where they disagree is largely over rates and the impact of the Flood.
Now to your argument, even assuming falsely a Creationist believes that, it would be no different to believe in parallel or alternate universes. How do you know that this universe didn't just begin? Your just an offbranch/spinoff of some choice made in another universe. So the argument you make is even fruitless on this point as well and has little to do with God.
Jul 11, 2011
Rank: 1 / 5 (3)
200 years ago, you could have entitled it "Huttonism Creeps into Mainstream Geology".
The article you reference, seems to describe creationists leaving out their religious bias, while describing the geology they were visiting.
It's not even a study based on evidence, just mere conjecture and assumption, out of a clear religious bias.
9/11 conspiracists have more credibility.
Jul 11, 2011
Rank: 5 / 5 (3)
That is not leaving out their religious bias. The article does indeed show, in several other comments, too, that they interpreted all the outcrops and roadcuts as showing results of flooding, even though the correct answers were not flooding.
Besides, geology has made huge strides in advancing their knowledge as a result of carbon dating and other molecular processes that have confirmed dating much older than that attributed to the 'great flood.' Read the whole story before you make comments on it. The story in physorg was only an excerpt of the complete article at:
http://www.earthm...icle/456
Jul 11, 2011
Rank: 1 / 5 (2)
I'm not sure how Ross can be accused either, considering he worked entirely within the current framework of standard geology for his talk.
The author here is grasping at straws. These men, despite their background, only seemed to address non religious reasons for why they believed these areas to be deluvial.
As to "wind blown" or deluvial, I don't know the areas well enough to comment. Perhaps the author could have made more comment as to why they are considered "wind blown", which is where the argument should be.
Jul 11, 2011
Rank: 1 / 5 (4)
Carbon dating is based on ratio. If the ratio was largely different in the past, modern carbon dating will only be good up to that point. Same reason you can't use it based on the nuclear bomb testing era. So if there was a Flood, carbon dating is only dependable up to about 4000 years, at least until you could determine the pre-Flood ratio.
Jul 11, 2011
Rank: 1 / 5 (4)
A global flood, as described in the bible, has plenty of potential energy for such chain reactions. The amount of carbaonate being dumped by subterranean water would also effect carbon dating.
For what we look at are mechanisms. One asserts long time, because the current decay rates or ratios are "normal". But just about any process or mechanism can be sped up or slowed down.
Jul 12, 2011
Rank: 5 / 5 (2)
In reality, "The date of a rock is reset when volcanic activity remelts it. The date of a piece of pottery is reset by the heat of the kiln. Typically temperatures greater than 400 degrees Celsius will reset the "clock". This is termed thermoluminescence."
It is also true that depth pressure creates heat, so pressure does effect the decay clock.
Jul 12, 2011
Rank: 5 / 5 (2)
Jul 12, 2011
Rank: 5 / 5 (2)
http://www.earthm...-7db-6-a
Jul 12, 2011
Rank: 5 / 5 (2)
It is patently false to say that that is that YEC adherents believe.
They are Scriptural literalists who maintain that all happened precisely as set forth in their translations of translations of the Torah, and at precisely the speed seemingly indicated by the genealogies there set forth.
Please do not think that all here as so gullible as to simply accept your self-serving definitions.
Jul 12, 2011
Rank: 1 / 5 (2)
It is surprising how much discussion goes on here about Young Earth Creationists. One might be led to believe that this is a religious site since so much time is spent arguing about a small fringe group of people.
You don't find such discussions in main stream religions because they don't care to waste time discussing irrelevancies.
Jul 12, 2011
Rank: 4 / 5 (4)
That's only been shown to hold true for certain elements under controlled circumstances, none of which are used for radiometric dating. Not all elements have the same mechanism for radioactive decay, so not all are going to be affected by changes in the electron orbitals.
Potential energy? Running water does not strip electrons.
Chain reactions? "Chain" is not a figure of speech with regards to chemical reactions. It refers to a specific subset of self-perpetuating reaction.
Sure, if the living organisms continued to digest after they were subjected to the flooding. Also if we were to use carbon dating for long-term geological purposes.
Jul 12, 2011
Rank: 1 / 5 (3)
Which is not a rate change though now is it? Your measuring the accumulated dose, after resetting.
For pottery it works well. Pottery is much more modern.
I was reading from the article. The word "continental" is not included by the author in the Ross quote. It is his wording afterward. Ross could have said anything from non local, regional to continental, but we don't know.
Jul 12, 2011
Rank: 1 / 5 (3)
You just described what I said the difference is. Why would I be patently false then? I said they disagree over rates, obviously with YEC holding to the genologies/chronology/order presented.
Jul 12, 2011
Rank: 1 / 5 (2)
The work is relatively new, and yes it has implications for radiometric dating. The electrical environment surrounding surrounding nuclei is quite critical and poorly understood.
Nuclear combustion experiments in Kiev have generated all known elements as a result, regardless of the initial elements being used.
Assuming the Flood was just "Running water" is like characterizing a hurricane as a faucet drip.
Jul 12, 2011
Rank: 1 / 5 (2)
My apologies if misused, the point is that there were a domino of events taking place. Similar in thought to an earthquake, then causing a tsunami, then wrecking Japan. As to electricity...
Mechanical stress causes piezoelectric effect which generates plenty of electricity. Considering the subterranean, confined "running water" being tidal pumped for 1500 years, the resulting release would have made short work not only of the crust's deformation and movement, but would have generated plenty of electricity.
Jul 12, 2011
Rank: 5 / 5 (4)
While the forces behind a tsunami, massive flood, etc. are extremely large on the macroscopic level, I don't see how they could cause that kind of effect on an electronically stable element, nor on an element that does not exhibit electron-related decay. Just because Beryllium can be affected doesn't mean that uranium will be.
Jul 12, 2011
Rank: 1 / 5 (2)
Crust collapsing and fluttering, or compression/tension cycles that would drive the piezoelectric effect, easily generating enough electricity to break down granite. Discharging like lightning throughout the crust, the possibilities become mechanisms like z-pinch or even shock collapse. In essence the entire upper crust becomes a nuclear engine due to the build up of super critical water and the release of all that water and energy.
Note the following link, describes these conditions, based on what Biblical indications are given for prior to the Flood.
http://www.creati...ty3.html
And an example of tidal pumping and its energy, can be seen from Enceladus, although it is poor in comparison due to Enceladus' make up.
Jul 13, 2011
Rank: 5 / 5 (1)
Once again, speak to the YEC adherents that drag it in.
Jul 13, 2011
Rank: 5 / 5 (1)
That is NOT the ONLY thing that they disagree about.
Jul 13, 2011
Rank: 5 / 5 (2)
The "logic" used to reach conclusions on this website hurts my brain.