From Newcastle University
Global cooling as significant as global warming
A “cold snap” 116 million years ago triggered a similar marine ecosystem crisis to those witnessed in the past as a result of global warming, according to research published today in Nature Geoscience.
The international study involving experts from the universities of Newcastle, UK, Cologne, Frankfurt and GEOMAR-Kiel, confirms the link between global cooling and a crash in the marine ecosystem during the mid-Cretaceous greenhouse period.
It also quantifies for the first time the amplitude and duration of the temperature change. Analysing the geochemistry and micropaleontology of a marine sediment core taken from the North Atlantic Ocean, the team show that a global temperature drop of up to 5oC resulted in a major shift in the global carbon cycle over a period of 2.5 million years.
Occurring during a time of high tectonic activity that drove the breaking up of the super-continent Pangaea, the research explains how the opening and widening of new ocean basins around Africa, South America and Europe created additional space where large amounts of atmospheric CO2 was fixed by photosynthetic organisms like marine algae. The dead organisms were then buried in the sediments on the sea bed, producing organic, carbon rich shale in these new basins, locking away the carbon that was previously in the atmosphere.
The result of this massive carbon fixing mechanism was a drop in the levels of atmospheric CO2, reducing the greenhouse effect and lowering global temperature.
This period of global cooling came to an end after about 2 million years following the onset of a period of intense local volcanic activity in the Indian Ocean. Producing huge volumes of volcanic gas, carbon that had been removed from the atmosphere when it was locked away in the shale was replaced with CO2 from the Earth’s interior, re-instating a greenhouse effect which led to warmer climate and an end to the “cold snap”.
The research team say this study highlights how global climate is intrinsically linked to processes taking place in the earth’s interior at million year time scales and that these processes can modify ecospace for marine life, driving evolution.
Current research efforts tend to concentrate on global warming and the impact that a rise of a few degrees might have on past and present day ecosystems. This study shows that if global temperatures swing the other way by a similar amount, the result can be just as severe, at least for marine life.
However, the research team emphasise that the observed changes of the earth system in the Cretaceous happened over millions of years, rather than decades or centennial, which cannot easily be related to our rapidly changing modern climate conditions.
“As always it’s a question of fine balance and scale,” explains Thomas Wagner, Professor of Earth Systems Science at Newcastle University, and one of the leaders of this study.
“All earth system processes are operating all the time and at different temporal and spatial scales; but when something upsets the balance – be it a large scale but long term natural phenomenon or a short and massive change to global greenhouse gases due to anthropogenic activity – there are multiple, potential knock-on effects on the whole system.
“The trick is to identify and quantify the initial drivers and consequences, which remains an ongoing challenge in climate research.”
Lucky he got that second-last paragraph in — his funding was teetering in the balance for a moment there..
‘The result of this massive carbon fixing mechanism was a drop in the levels of atmospheric CO2, reducing the greenhouse effect and lowering global temperature.’
Cause or effect?
The result of this massive carbon fixing mechanism was a drop in the levels of atmospheric CO2, reducing the greenhouse effect and lowering global temperature.
Why do these academics continue to claim carbon dioxide must be the cause of every global temperature change? The level of carbon dioxide changes after the change in temperature. The effect of carbon dioxide is logarithmic in any case so large reductions from 1200 to 600ppm would only have the same effect as 600 to 300ppm.
Walking back out of this ‘carbon fixation’ is going to be very difficult for academia.
Wouldn’t it have been the case that the cooling temperatures then increased oceanic uptake of CO2?
They mention increased tectonic activity and we know that that causes cooling by injectiin material into the stratosphere.
Additional sea areas around the equatorial regions as part of Pangea drifted polewards would be enough to energise the biosphere despite any general cooling process in the background.
Add increased ocean absorption to a larger equatorial biosphere and that would deplete atmospheric CO2.
The conclusion that less CO2 caused the cooling is not warranted.
As for the recovery 2 million years later it is hard to see how intense volcanic activity in the Indian Ocean would cause such warming when we all see that volcanos cause cooling.
This “study” is so bad, that it can’t even be called pseudoscience. It is carboncentric anti-science.
“Marine Ecosystem” = ocean? All climate in terms of “carbon”? They have all the right jargon and climate correct wording without quantifying the CO2 losses and gains. As mentioned above, volcanic activity warms when convenient as it cools when convenient. Is recent volcanic activity the cause for this period of global warming then? Sounds like an interesting study of the formation of African shales if they had stuck to the facts and not tried all the AGW buzz words.
Another result from models. Relying on the GHE, when it blatently does not work as advertised, ignores the obvious vast amounts of SO2 aerosols that would cool the earth. During such a time there would also be a vast amount of CO2 injected which they ignore only that some could be sequestered thus reducing temperatures.
The same Indian Ocean/Pacific Ocean volcanism is shown to have caused, in a separate paper, global warming.
Why do these academics continue to claim carbon dioxide must be the cause of every global temperature change?
MONEY, MONEY, MONEY.
“these processes can modify ecospace for marine life, driving evolution.”
Boy, they are even trying out a new buzzword. While I agree that tectonics have a wide influence….wait a minute, this is just a buzzwording of a well-known effect, I’m afraid. Nice try, kids.
“our rapidly changing modern climate conditions”
Where on EARTH do we see ‘rapidly changing climate conditions”?
” the research explains how the opening and widening of new ocean basins around Africa, South America and Europe created additional space where large amounts of atmospheric CO2 was fixed by photosynthetic organisms like marine algae.”
Am I missing something, or didn’t the breakup of Pangaea just result in several ocean basins of about the same area as the single ocean that existed previously?
This blurb on the new paper can give the impression Pangaea broke up around 116 MYA in a single event and that is very far from the truth. I don’t know if the actual paper is also misleading but for clarification here is a summary of the action:
There were three major phases in the break-up of Pangaea. The first phase began in the Early-Middle Jurassic (about 175 Ma), when Pangaea began to rift from the Tethys Ocean in the east to the Pacific in the west, ultimately giving rise to the supercontinents Laurasia and Gondwana. The rifting that took place between North America and Africa produced multiple failed rifts. One rift resulted in a new ocean, the North Atlantic Ocean.[14]
The Atlantic Ocean did not open uniformly; rifting began in the north-central Atlantic. The South Atlantic did not open until the Cretaceous when Laurasia started to rotate clockwise and moved northward with North America to the north, and Eurasia to the south. The clockwise motion of Laurasia led to the closing of the Tethys Ocean. Meanwhile, on the other side of Africa and along the adjacent margins of east Africa, Antarctica and Madagascar, new rifts were forming that would not only lead to the formation of the southwestern Indian Ocean but also open up in the Cretaceous.
The second major phase in the break-up of Pangaea began in the Early Cretaceous (150–140 Ma), when the minor supercontinent of Gondwana separated into multiple continents (Africa, South America, India, Antarctica, and Australia). About 200 Ma, the continent of Cimmeria, as mentioned above (see “Formation of Pangaea”), collided with Eurasia. However, a subduction zone was forming, as soon as Cimmeria collided.[14]
This subduction zone was called the Tethyan Trench. This trench might have subducted what is called the Tethyan mid-ocean ridge, a ridge responsible for the Tethys Ocean’s expansion. It probably caused Africa, India and Australia to move northward. In the Early Cretaceous, Atlantica, today’s South America and Africa, finally separated from eastern Gondwana (Antarctica, India and Australia), causing the opening of a “South Indian Ocean”. In the Middle Cretaceous, Gondwana fragmented to open up the South Atlantic Ocean as South America started to move westward away from Africa. The South Atlantic did not develop uniformly; rather, it rifted from south to north.
Also, at the same time, Madagascar and India began to separate from Antarctica and moved northward, opening up the Indian Ocean. Madagascar and India separated from each other 100–90 Ma in the Late Cretaceous. India continued to move northward toward Eurasia at 15 centimeters (6 in) a year (a plate tectonic record), closing the Tethys Ocean, while Madagascar stopped and became locked to the African Plate. New Zealand, New Caledonia and the rest of Zealandia began to separate from Australia, moving eastward toward the Pacific and opening the Coral Sea and Tasman Sea.
The third major and final phase of the break-up of Pangaea occurred in the early Cenozoic (Paleocene to Oligocene). Laurasia split when North America/Greenland (also called Laurentia) broke free from Eurasia, opening the Norwegian Sea about 60–55 Ma. The Atlantic and Indian Oceans continued to expand, closing the Tethys Ocean.
It also strikes me as strange (well not really) that CO2 gets top billing and ocean current changes / new oceans & their effect on climate don’t rate a mention.
Black Diamond or Black Swan?
If you can see that the logical extension of the UAH data series in this presentation should next contain a Black Diamond (a falling node) and can place it somewhere on the graph with good arguments then welcome to short terminal climate prediction!
http://s1291.photobucket.com/user/RichardLH/story/70051
A black swan moment?
Damn auto complete – short term climate prediction!
The greenhouse effect is well-established physics so this study naturally builds on that knowledge to investigate the effect of global cooling on marine life. The fact that the cooling is caused by changing carbon dioxide composition of the atmosphere appears to be incidental, rather than central to the study.
Interesting research.
Why is it that any reduction in mean temperatures, however large and even for millions of years is always referred to in the media as a “cold snap”, as if cooling/freezing is too trivial to be concerned with? Whereas of course any increase in temperatures is proof positive of warming models veracity. Funny thing, that.
This did not happen.
I’m running the highest resolution temperature database of anyone (equivalent to 0.5 million year smoothing) and I have all the CO2 estimates produced from reliable methods.
Here is Temp versus CO2 from 170 million years ago to 100 million years ago. Nothing happened at 116 Mya and CO2 was consistently between 700 ppm to 3,000 ppm over this period.
I picked the time-frame just to highlight something which is rarely mentioned. There was a significant ice age at 160 Mya when East Asia drifted across the North Pole. The dinosaurs actually lived in a period when large glaciers existed at the North Pole – where Siberia was at the time.
http://s7.postimg.org/h3nvbh5cb/Temp_CO2_160_100_Mya.png
http://www2.nau.edu/rcb7/160_1st.jpg
Now what was happening at 116 Mya was that South America and Africa had just started breaking apart (from the south up to the north) (South America splitting with Antarctica and Australia in tow) and 116 Mya seems to be the most rapid period of this unzipping. So, I’m assuming, large volcanic activity has distorted whatever data the authors were using.
http://s23.postimg.org/qgci3rx8r/South_Pole_116_Mya.png
PowerPoint animation of Gondwana breaking up – big file but will be very interesting for those into plate tectonics.
http://www.ig.utexas.edu/research/projects/plates/movies/akog.ppt
“This study shows….”
‘Suggests’ used to be the operative word in such studies. We have seen so much certainty in climate science, the same kind of confident phraseology used in studies that are now known to be balderdash. I’ll bet you this is the result of the Schneider admonition that climate scientists should not indicate any uncertainties. Indeed, the plethora of this type of semantics suggests that it was promulgated as a policy, probably arising from the advice of the slick communications consultants that were hired to help these poor honest scientists to compete for the hearts and minds with the big bad oiled and coaled skeptics (who, ironically use homely things like “bullshit button” and other such no-nonsense terms).
A problem with fonts and rendering:
The way my browser rendered the above sentence, it came out looking like “fifty Centigrade”. It should, of course, read “five degrees Centigrade”.
Icarus62 says:
June 17, 2013 at 5:21 am
Into the Koolaid kind of early, aren’t you? Always fun when a True Believer describes the earths’ complex, multi-cyclic climate system as “simple physics”.
Submarine Volcanic activity…………………
“Locked away in the shale” and then…………..”was replaced with CO2 from the Earth’s interior,”
Cripes, sedimentary carboniferous, cretaceous deposits, ie the stuff wot locks away CO2 – is usually via fossilisation of plant life or, fossilisation of billions of calciferous shells of marine fauna and laid down over millennia in suitable marine environments, locked away it certainly is – till we dig, mine, drill it – bring it back to the surface and burn it, pulverise it and use it to build with.
“was replaced with CO2 from the Earth’s interior, re-instating a greenhouse effect which led to warmer climate”.
Yet there was no great coral mass extinction, no massive ocean acidification, with all that increase in C02.
“A “cold snap” 116 million years ago triggered a similar marine ecosystem crisis…”
Oh dear, if only humans had been around to pass a Climate Change tax.
Where’s my red BS button. I’m on my 10th one too. The last 9 wore out!
Pure conjecture, most people do not know, YET, that the volcanic erruptions of El Chichon and Pinatubo caused long term warming by altering the water vapor content of the stratosphere hence altering the amount of shortwave IR that the surface receives after the Sulfuric Acid clouds and short term cooling effects dissipated. How could the authors be so sure that similar conditions did not cause the warming millions of years ago. Peer reviewed literature indicates that at least 30% of the warming over the last two decades were caused by just two Volcanic erruptions. CO2 again is likely an effect not a cause.
Oh good, someone else pointed out the ridiculousness which a 50 Kelvin temperature swing would involve.
50°C cooling?!! Did someone use a small ‘oh’ for [alt]0176 ?
Too much of the effects of climate change are rather esoteric.
It’s all about food !
“Global cooling as significant as global warming”
I’ll take a two degree uptick to a drop of two degrees any day.
One lengthens the growing season the other shortens it. Guess which is better?
“… a similar marine ecosystem crisis to those witnessed in the past as a result of global warming”
I’m not aware of any such crises. Can anyone educate me?
@Icarus62
“The greenhouse effect is well-established physics so this study naturally builds on that knowledge….”
Well established physics for a controlled environment inside a bell jar, but not for a dynamically changing and chaotic ocean/atmosphere system, which current, real-time observations are now revealing.
@- Bill Illis
“Here is Temp versus CO2 from 170 million years ago to 100 million years ago. Nothing happened at 116 Mya and CO2 was consistently between 700 ppm to 3,000 ppm over this period.”
http://s7.postimg.org/h3nvbh5cb/Temp_CO2_160_100_Mya.png
You have labeled the temperature estimates on your graph as derived from ice core dO18.
But the ice cores only go back around 1 million years, not 160million, the dO18 data you reference is sediment data.
That has problems of indicating the local temperature, not the global, the time resolution is poor and it relies on computer modelling of the water-ice balance to ‘correct’ the temperature as the greater the amount of ice the greater the adjustment in the dO18 to temperature conversion.
The data on past CO2 levels is also rather less than robust. It too relies on modelling and has a poor temporal resolution. There are also two other correction or factors that need to be included, the state of the Milankovitch cycle and the resultant distribution of solar energy and the change in solar luminosity over time.
That CO2 IS the main factor causing temperature changes is a result of the measured physical properties of CO2 and the radiative transfer equations. Both of these were discovered, understood and established long before computer modelling or any supposed Lysenkoist hoax could be underway. The absorptive properties of CO2 were measured around the time of Darwin’s ‘Origin of Species’ the radiative transfer equations in the mid fifties as part of military research into heat detection of missiles. The certainty and consensus that CO2 increases warm the climate is far stronger than the 97% quoted for AGW in general.
During the mid-Cretaceous period co2 was 2 to 4 times higher than today. Life on Earth perished, the oceans boiled, corals became bleached, the oceans steamed with acid and triggered galloping runaway warming.
@Jimbo
“During the mid-Cretaceous period co2 was 2 to 4 times higher than today. Life on Earth perished, the oceans boiled, corals became bleached, the oceans steamed with acid and triggered galloping runaway warming.”
If true, then that amount would be 800 to 1600 ppm, still less than one to two tenths of one percent of the atmosphere. I’m doubtful that such a concentration, in and of itself, would be responsible for the oceans boiling and for runaway warming.
Complete alarmist nonsense.
The result of this massive carbon fixing mechanism was a drop in the levels of atmospheric CO2, reducing the greenhouse effect and lowering global temperature
How does CO2 at ambient temperature emit more radiation than air at ambient temperature?
Surely the radiation balance isn’t changed by doubling or reducing CO2.
@Jimbo
I am waiting for at least one study to appear that actually describes how thousands of species became extinct due to runaway global warming during a past geological period. I wonder if it will ever appear.
Interesting work. Good post.
Izen,
Your problem is that because the optical and radiative transfer properties of CO2 are well understood does not mean its behavior in the system is.
Just more naturegeoscience.spam in the tired formula. A very interesting time in tectonic history nonetheless.
Geoff Withnell says:
June 17, 2013 at 4:52 am
” the research explains how the opening and widening of new ocean basins around Africa, South America and Europe created additional space where large amounts of atmospheric CO2 was fixed by photosynthetic organisms like marine algae.”
Am I missing something, or didn’t the breakup of Pangaea just result in several ocean basins of about the same area as the single ocean that existed previously?
==================================================
My thoughts, exactly, Geoff. The breakup of Pangaea surely created new shoreline, but increasing the amount of ocean? if new ocean had been created to affect the CO2 content, then new water would have needed to be added to the world. This mechanism is breaking down.
They took information that tended to discount AGW and tortured it into an argument regarding AGW. Pathetic. And brings into question the mental qualifications of these researchers to ‘research’.
Climate science, as perfected by the Team, is performed as follows. Descide on your outcome and them figure out how to get there with the patchy, inconsistent and degraded proxy data. The “Trick” ( tm) is to splice anything on that you need to get the result you want. Unfortunate turn of phrase in the last paragraph. But then how good is 100 million year old data?? Tricks indeed.
Bill Illis says:
June 17, 2013 at 5:37 am
This did not happen.
Srewart Pid says:
June 17, 2013 at 5:07 am
This blurb on the new paper can give the impression Pangaea broke up around 116 MYA in a single event and that is very far from the truth. I don’t know if the actual paper is also misleading but for clarification here is a summary of the action:
There were three major phases in the break-up of Pangaea. The first phase began in the Early-Middle Jurassic (about 175 Ma), when Pangaea began to rift from the Tethys Ocean in the east to the Pacific in the west, ultimately giving rise to the supercontinents Laurasia and Gondwana.
…
The second major phase in the break-up of Pangaea began in the Early Cretaceous (150–140 Ma), when the minor supercontinent of Gondwana separated into multiple continents (Africa, South America, India, Antarctica, and Australia). About 200 Ma, the continent of Cimmeria, as mentioned above (see “Formation of Pangaea”), collided with Eurasia.
…
The third major and final phase of the break-up of Pangaea occurred in the early Cenozoic (Paleocene to Oligocene). Laurasia split when North America/Greenland (also called Laurentia) broke free from Eurasia, opening the Norwegian Sea about 60–55 Ma. The Atlantic and Indian Oceans continued to expand, closing the Tethys Ocean.
It also strikes me as strange (well not really) that CO2 gets top billing and ocean current changes / new oceans & their effect on climate don’t rate a mention.
Thanks Bill and Sreward for solid facts to counter this despicable propaganda.
That so-called “scientists” can brush aside decades of painstaking research and foist this story on the media of CO2 driving climate change without any factual basis, is nothing short of criminal.
I don’t want to sound hysterical here but it is just breath-taking how such research starts with the conclusion and works backward – they know implicitly that temperature change can ONLY be caused by CO2 so the role of the discussion section is simply to make a conjecture as to how the cooling was CO2 driven – a conjecture immediately seized on by the media as peer-reviewed consensus and settled science. No other possible factors influencing climate, such as the elephant in the room – ocean deep circulation – are even mentioned.
In the light of many previous comments by Bill Illis on the dominant and decisive role of ocean circulation on global temperatures – such as the establishment of the circum-polar current as the cause of the current cold period – it is very obvious here that the widening south Atlantic in the mid-Cretaceous established Arctic to Antarctic Atlantic circulation for the first time, which must have had a profound effect on global circulation and temperature. The rift between Africa and South America started earlier than 116 MYa, but 116 MYa might have been the time when the deep ocean connection between north and south Atlantic became large enough to allow significant deep ocean circulation.
The dance of the continents is nicely animated in this youtube video.
The humorous aspect of this entire discussion is that icarus62, izen and Ryan would buy this nonsense hook, line and sinker. Perfect demonstration of the critical thinking skills of true believers.
A change of 50 degrees C, eh? See paragraph 3. That equates to 90 degrees Fahrenheit; thus, our current 78 degrees F here in Virginia would have changed to -12 degrees F. How much faith do they have that the causes they have identified would produce that effect, in that quantity? I have deep reservations about that–indeed, about all of the estimates these people seem so sure of with regard to past temperatures and climatic conditions. I do not mean the well-documented warmth of the Medieval Warm Period, nor the well-recorded cold of the Little Ice Age; those periods fall well into accepted human recorded history and have, in addition to written notations, various markers and signs in the environment (Greenland burial grounds now bound up in permafrost, vineyards in Scotland, etc.). To what extent do we actually trust numbers extrapolated from partial, fragmentary, and to some extent conjectural data? For me, that extent is quite limited.
” it is very obvious here that the widening south Atlantic in the mid-Cretaceous established Arctic to Antarctic Atlantic circulation for the first time,”
Um, I think you might be forgetting about the Panthalassic Ocean covering the rest of the planet.
Bob says:
June 17, 2013 at 4:05 am
“Marine Ecosystem” = ocean? All climate in terms of “carbon”? They have all the right jargon and climate correct wording without quantifying the CO2 losses and gains.
correct, the right jargon and correct wording
Srewart Pid says:
June 17, 2013 at 5:07 am
It also strikes me as strange (well not really) that CO2 gets top billing and ocean current changes / new oceans & their effect on climate don’t rate a mention.
exactly. If we would have for instance Antarctica packed together with Australia we would have a total different climate. How can so called scientists go over it and try to blame all on CO2? When we know there is no correlation between CO2 and historical temperature on the scale of millions of years?
This “study” is at the same level with the killing of the farting megafauna causing the Younger Dryas study, the Genghis Khan green lord study and the conquistadores causing Little Ice Age…=> very difficult to be any lower.
The original article has it as five degrees centigrade. “5oC” is a typo.
“Why do these academics continue to claim carbon dioxide must be the cause of every global temperature change?”
Huh? here the cause is
“Occurring during a time of high tectonic activity that drove the breaking up of the super-continent Pangaea, the research explains how the opening and widening of new ocean basins around Africa, South America and Europe created additional space where large amounts of atmospheric CO2 was fixed by photosynthetic organisms like marine algae.”
“the” cause is never simply C02. As we know from fundamental physics is you add C02 you will end up with a warmer world, provided other forcings stay roughly at the same levels. If you decrease c02 you will end up with a cooler world, provided other forcings stay the same.
For example, if you decreased C02 but increased solar output, cooling or warming would depend on which was the greater forcing.
So the cause here isnt simply C02, but starts with tectonic activity and then includes marine life.
remember what skeptics say.. the climate is complex.. that C02 plays a role should come as no surprise. Neither should it be a surprise that marine life plays a role.
Steven Mosher says:
June 17, 2013 at 12:08 pm
So the cause here isnt simply C02, but starts with tectonic activity and then includes marine life.
remember what skeptics say.. the climate is complex.. that C02 plays a role should come as no surprise. Neither should it be a surprise that marine life plays a role.
As in your link: “created additional space where large amounts of atmospheric CO2 was fixed by photosynthetic organisms like marine algae.”
“The result of this massive carbon fixing mechanism was a drop in the levels of atmospheric CO2, reducing the greenhouse effect and lowering global temperature.”
Again without quantifying what drop of CO2 and what drop of global temperature – where is any other reason for the temperature drop Steven in the article?
“This period of global cooling came to an end after about 2 million years following the onset of a period of intense local volcanic activity in the Indian Ocean. Producing huge volumes of volcanic gas, carbon that had been removed from the atmosphere when it was locked away in the shale was replaced with CO2 from the Earth’s interior, re-instating a greenhouse effect which led to warmer climate and an end to the “cold snap”.”
The end is again thought to have been done all alone by the “volcanic gas” – where here CO2 is ment again.
So it goes only about CO2 leading the temperature in the article Steven, but pls point out where other reasons for temperature are said, I might have missed those…
CO2 played a much more minor role then some climate scientists would like to make us believe. One of the arguments of skeptics is the geological record, that we clearly know and show, where data is available and it does not have any correlation between temperature and CO2 as you also know.
Such articles – without any science in them – allow for speculations and are used as “proof” that the skeptics are not right in geology.
As there is no quantification, no science in the article skeptics cannot rebut it, as there is nothing to rebut, just speculations. There is no science in it.
“global temperature drop of up to 5oC “, really?
Is there a ocean floor that is 2 million years old?
http://upload.wikimedia.org/wikipedia/commons/c/cb/Earth_seafloor_crust_age_poster.gif
ooops, sorry, should have read, or at least scanned, the comments before mine.
“My thoughts, exactly, Geoff. The breakup of Pangaea surely created new shoreline, but increasing the amount of ocean? if new ocean had been created to affect the CO2 content, then new water would have needed to be added to the world. This mechanism is breaking down.”
The paper makes no claim about increasing global ocean area.
“Is there a ocean floor that is 2 million years old?”
Yes, there is ocean floor that is 270 million years old.
http://geosciencebigpicture.com/2013/01/06/charybdis-and-…floor-on-earth/
phlogiston says:
June 17, 2013 at 9:41 am
—————————-
Thanks for your post, especially the visual aid.
Look, it is completely plausible that separating Pangea created more biological activity. The center of the Panthalassic ocean may have had huge “dead zones” like those we see today where a lack of nutrients limited plankton. Splitting the continents would have had the effect of creating nutrient rich runoff shelves teeming with life. Have you ever noticed weeds are taller at the edge of the freeway?
If proliferation of life and consequent drawdown of CO2 were sufficient to cause cooling it surely would have happened in the Devonian when plants colonized land. It did not. O2 skyrocketed and CO2 plummeted but no cooling occurred. Cooling awaited a random time in the late Carboniferous and continued into the middle Permian. This Carboniferous/Permian cooling episode is the most recent to the one we live in, the Pleistocene, beginning two or three million year ago.
There are Jurassic, and possibly even Cretaceous tillites indicating glaciation. Whether Siberasia actually crossed the north pole is debatable but clearly this was the closest any continent ever came to doing so.
The biosphere is carbon limited. Increased biological activity will draw down atmospheric CO2, but the geological record is quite clear that the only reliable relationship between temperature and CO2 is that a warming planet always increases atmospheric CO2 and a cooling planet decreases it.
What one should take home from this paper is that sudden episodes of unexplained cooling can happen at any time, in any continental configuration, even during 250 million year otherwise ice free periods, and we really don’t have any idea why.
gymnosperm says:
June 17, 2013 at 11:16 am
” it is very obvious here that the widening south Atlantic in the mid-Cretaceous established Arctic to Antarctic Atlantic circulation for the first time,”
Um, I think you might be forgetting about the Panthalassic Ocean covering the rest of the planet.
What I meant was that, in addition to the other big Pacific-like ocean, there was now a second ocean, the Atlantic, also extending from pole to pole, establishing the complex deep ocean global circulation that we now have. Note – although the Atlantic is (still) smaller than the Pacific, the largest site by volume of cold water downwelling which drives the thermo-haline deep circulation, is the Norwegian sea at the North Atlantic. This motor of global deep circulation may have started around the mid Cretaceous. If so, it would probably have cooled global climate. CO2 by contrast, cools or warms nothing.
It seems this study has now made it onto a connection to google maps of all things. A click on ‘Climate Change; brought this up. The are really pushing this brainwashing aren’t they.
Gail Combs
Yes it would seem so.
If its all true, why do they need to push it so hard? “Methinks the king doth protest too much”.
gymnosperm says:
June 17, 2013 at 11:35 pm
Look, it is completely plausible that separating Pangea created more biological activity. The center of the Panthalassic ocean may have had huge “dead zones” like those we see today where a lack of nutrients limited plankton. Splitting the continents would have had the effect of creating nutrient rich runoff shelves teeming with life. Have you ever noticed weeds are taller at the edge of the freeway?
If proliferation of life and consequent drawdown of CO2 were sufficient to cause cooling it surely would have happened in the Devonian when plants colonized land. It did not. O2 skyrocketed and CO2 plummeted but no cooling occurred. Cooling awaited a random time in the late Carboniferous and continued into the middle Permian.
There is a nice PNAS paper by Beerling and Berner 2005 describing and modelling the brief period in the Devonian-Carboniferous of runaway feedback between, on one hand, the spread of plants – in particular trees – across land and the evolution of both increased height and leaf width plus stomatal density, and on the other hand, decreasing CO2 concentration in air. Plants before this period experiencing sky-high CO2 hardly even needed leaves, just a few holes here and there to take in CO2. CO2 supply and demand led to a CO2 crash and made trees and plants much more efficient CO2-gatherers. If ever there was a period in which to study how changing CO2 levels drove changing temperatures – this is it, where a clear cause – the spread and evolution of plants / trees – led to a clear effect – sharply falling CO2. But the CAGW palaeo-revisionists for some reason avoid this period. Why? The answer is as you state – there was no corresponding temperature fall with the CO2 fall. A sharp temperature drop did follow the CO2 decrease – about 60 million years later, thus it was clearly unrelated to the CO2 drop.
phlogiston says:
June 18, 2013 at 12:56 am
===========================
It is true that today Arctic bottom water can only escape into the north Atlantic because the Bearing Straight is effectively closed. This was not true in the Jurassic.
Just one more thing…
This was a 2.5 million year episode. We have no way of knowing if our wimpy little Pleistocene at about the same time scale is one of these little hiccoughs or the beginning of a grander episode like the Ordovician or the Carboniferous/Permian glacial periods.. Your guess is as good as mine, but mine is that it is the beginning of a large scale event based on the steady decline over roughly 50 million years since the PETM.
gymnosperm says:
June 17, 2013 at 10:45 pm
——————————-
I misread the article.
But the link i provided suggests the oldest ocean floor is 180 Ma and your link is dead.
http://upload.wikimedia.org/wikipedia/commons/c/cb/Earth_seafloor_crust_age_poster.gif
gymnosperm says:
June 18, 2013 at 10:15 pm
Just one more thing…
This was a 2.5 million year episode. We have no way of knowing if our wimpy little Pleistocene at about the same time scale is one of these little hiccoughs or the beginning of a grander episode like the Ordovician or the Carboniferous/Permian glacial periods.. Your guess is as good as mine, but mine is that it is the beginning of a large scale event based on the steady decline over roughly 50 million years since the PETM.
There is one school of thought that such a deep cooling millions of years long happens every 150 million years. This is approximately consistent with the following cold periods:
590 MYa (preCambrian, Marinoan glaciation)
440 MYa (end-Ordovician Saharan-Andean glaciation)
290 MYa (Carboniferous-Permian glaciation)
140 MYa (Jurassic-Cretaceous cold period)
10 MYa in future
The suggested reason is that 150 MY is the orbit period of our galaxy and that our arm of the galaxy flies through the same cloud of bad stuff in that part of space with every revolution. Its a Svensmark-related idea I believe.
Kajajuk says:
June 19, 2013 at 5:49 am
=======================
Wikipedia is a wonderful service, but if you have ever tried to help them get up to speed on issues where you have some expertise, you quickly learn why they are not up to speed.
Try this:
http://wp.me/p1uHC3-7H
Failing that, geosciencebigpicture.com; archives; Charybdis and the Oldest Ocean Floor on Earth.
phlogiston says:
June 19, 2013 at 3:03 pm
=========================
Yes, the idea predates Svensmark, and it is a good one. Even more interesting is the possibility we might get pelted by a lot of rocks out there in the spiral arm. Still, the periodicity seems forced to me, a la Milankovitch, and I am not yet prepared to buy into the Jurassic /Cretaceous episode as full fledged.
thanks for sharing gymnosperm,
i get frustrated by pay-walled boundaries or queries that return news releases and tend to settle on wiki for info. The page(s) your referenced are fascinating…
kjjk