From GFZ GEOFORSCHUNGSZENTRUM POTSDAM, HELMHOLTZ CENTRE
When continents break it gets warm on Earth
Rift zones released large amounts of CO2 from depth, which influenced global climate change
The concentration of carbon dioxide (CO2) in the atmosphere determines whether the Earth is in greenhouse or ice age state. Before humans began to have an impact on the amount of CO2 in the air, it depended solely on the interplay of geological and biological processes, the global carbon cycle. A recent study, headed by the GFZ German Research Centre for Geosciences in Potsdam, shows that the break-up of continents – also known as rifting – contributed significantly to higher CO2 concentrations in the atmosphere.
The carbon distribution on Earth is highly unbalanced: In fact only one-hundred-thousandth of the carbon dioxide on our planet is found in the atmosphere, biosphere and the oceans with the remaining 99.999% bound in the deep Earth. However, this enormous carbon store at depth is not isolated from the atmosphere. There is a constant exchange between the underground and the surface over millions of years: Tectonic plates that sink into the deep mantle take large amounts of carbon with them. At the same time it was believed that deep carbon is released due to volcanism at mid-oceanic ridges in the form of CO2.
In the current study, published in Nature Geoscience, the research team comes to a different conclusion. Although volcanic activity at the bottom of the ocean floor causes CO2 to be released, the main CO2 input from depth to the atmosphere, however, occurs in continental rift systems such as the East African Rift (Fig. 1) or the Eger Rift in Czech Republic. “Rift systems develop by tectonic stretching of the continental crust, which may lead to break-up of entire plates”, explains Sascha Brune from GFZ. “The East African Rift with a total length of 6,000 km is the largest in the world, but it appears small in comparison to the rift systems which were formed 130 million years ago when the supercontinent Pangea broke apart, comprising a network with a total length of more than 40,000 km.”
With the help of plate tectonic models of the past 200 million years and other geological evidence scientists have reconstructed how the global rift network has evolved. They have been able to prove the existence of two major periods of enhanced rifting approx. 130 and 50 million years ago. Using numerical carbon cycle models the authors simulated the effect of increased CO2 degassing from the rifts and showed that both rifting periods correlate with higher CO2 concentrations in the atmosphere at that time.
“The global CO2 degassing rates at rift systems, however, are just a fraction of the anthropogenic carbon release today”, adds Brune. “Yet, they represent a missing key component of the deep carbon cycle that controls long-term climate change over millions of years.”
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Link to the paper: https://www.nature.com/articles/s41561-017-0003-6
Potential links between continental rifting, CO2 degassing and climate change through time
Abstract
The concentration of CO2 in the atmosphere is a key influence on Earth’s climate. Today, significant quantities of CO2 are emitted at continental rifts, suggesting that the spatial and temporal extent of rift systems may have influenced deep carbon fluxes and thus climate change throughout geological time. Here we test this hypothesis by conducting a worldwide census of continental rift lengths over the last 200 million years. We estimate tectonic CO2 release rates through time and show that along the extensive Mesozoic and Cenozoic rift systems, rift-related CO2 degassing rates reached more than 300% of present-day values. Using a numerical carbon cycle model, we find that two prominent periods of enhanced rifting 160 to 100 million years ago and after 55 million years ago coincided with greenhouse climate episodes, during which atmospheric CO2 concentrations were more than three times higher than today. We therefore propose that continental fragmentation and long-term climate change could plausibly be linked via massive CO2 degassing in rift systems.
This is just another Potsdam-raid to cement the CO2 hypothesis. And helplessly wrong.
Closing of the American isthmus joining North and South America 2.8 million years ago was probably more important climatically.
Spot on there, tomO. Some realism at last…..
I seem to recall reading about continental glaciers during the Jurassic, when CO2 concentrations were MUCH higher than now. CO2 may have a minuscule effect, but other factors, like where our solar system is in relation to the galactic arms, solar output, etc. FAR outweigh CO2.
https://www.sciencedaily.com/releases/2015/12/151211124428.htm
Makes sense and doesn’t favour CACA faith. Somewhat redundant statement, I know.
Carbonatite and kimberlite intrusives and their kin have originated from deep within the Earth’s mantle – around 600 km down in the case of kimberlite. Such intrusives are totally unrelated to rift zones and the movement of continents relative to one another. Intrusive carbonatite looks very much like crystalline granite but its principal component is carbonate. The gas associated with kimberlites was mainly carbon dioxide, with native carbon in the form of diamonds being an occasional feature.
Carbonatite and kimberlite intrusives and their kin have originated from deep within the Earth’s mantle – around 600 km down in the case of kimberlite. Such intrusives are totally unrelated to rift zones and the movement of continents relative to one another. Intrusive carbonatite looks very much like crystalline granite but its principal component is carbonate. The gas associated with kimberlites was mainly carbon dioxide, with native carbon in the form of diamonds being an occasional feature.
Wattsupwiththat is always twisting real science to keep the gullible from knowing the truth.
[??? .mod]
Any sign of additional CO2 over the rift zones spotted by our new CO2 satellite?
“Any sign of additional CO2 over the rift zones spotted by our new CO2 satellite?” Most of the 65,000 km of rifting is in deep ocean and the CO2 emitted will be dissolved into very cold water. Check on Lake Magadi in Kenya to appreciate how much carbonate is precipitated at surface.
Can anyone explain why the collective denier voice of WUWT is bashing this article as if it has a warmist view ? Everyone sounds so silly because they don’t realize it actually supports their side. It claims climate scientists “forgot” or don’t take into account the natural source of CO2 caused by degassing of rifts, an argument that undercuts AGW. You all don’t seem to realize you are fighting a non existent enemy of your own making and harming your own ideology. Feels very Shakespearean, actually, a good classic tragedy all the way around. Humbling too, as it highlights the rather pathetic aspects of the human condition.
“Yeah right” wrote, “Can anyone explain why the collective denier voice of WUWT is bashing this article as if it has a warmist view ? Everyone sounds so silly because they don’t realize it actually supports their side…”
You don’t get it, YR. The collective voice of WUWT is not mainly about “our side” vs “their side,” it is about good science vs. junk science. Or, if you prefer, it is about what is correct vs. what is untrue.
I am skeptical of climate alarmism because the best evidence is that anthropogenic global warming is real, but modest and benign. Should the best evidence change, so will my opinion.
“When my information changes, I alter my conclusions. What do you do, sir?”
– John Maynard Keynes (paraphrased)
On climate blogs (and presumably on most blogs which don’t pre-moderate), there’s a certain percentage of dummkopf comments, from “both sides” of the argument: some from the political Left and some from the Right. But there are two noticeable differences (other than the differing viewpoints) between “skeptic” blogs like WUWT and most “alarmist/activist” blogs like
GregLaden“RobertScribbler”.1. The alarmist/activist blogs are usually censored to enforce the blog owner’s viewpoint, and suppress the “other side.” WUWT obviously isn’t.
2. On WUWT, nonsense from either side gets critiqued and debunked, but on most alarmist/activist blogs even the most preposterous and ridiculous nonsense from “their side” stands uncriticized, and comments from the “other side” (skeptics/lukewarmists) are attacked mercilessly regardless of whether they are reasonable.
In other words, YR, like you, most of the “regulars” at “alarmist/activist” blogs like
GregLaden“RobertScribbler” are mainly concerned about “which side” someone and his remarks are on, and much less concerned about what is actually correct.[Because you asked so nicely. -mod]
Correction:
Moderators, I used the wrong example. Would you please change “GregLaden” to “RobertScribbler” the two places where it appears in my comment above?
Very sorry to have put you to the trouble!
Thank you, mod! I make lots of mistakes, but perhaps the worst of them are when, due to some sort of brain fart, I point a finger of blame at the wrong person.
“Can anyone explain why the collective denier voice of WUWT is bashing this article as if it has a warmist view ?” Geology seems to be one of those sciences where every commentators opinion carries as much weight as that of an actual experienced geologist. There’s a reason that the Almighty gave each of us two eyes, two ears but only one mouth.
I swear a skimmed an article last year about el nino events being a cyclical heat release from the inner-earth’s core through volcano or rifts. I would love to read that in more depth. Anybody know about this or did I just dream about it?
The concentration of carbon dioxide (CO2) in the atmosphere determines whether the Earth is in greenhouse or ice age state.
The very first sentence is infantile imbecilic anti-sense.
The temperature of earth, and whether it is in an ice age or not, determines the CO2 level.
Not the other way round.
CO2 is just another proxy of global temperature.
I love it when the warmists use the term “pre-industrial”.
It shows how narrow-minded, uncurious and stupid they are.
Which pre-industrial level?
500 ppm in the Palaeocene-Eocene?
1000 ppm in the Cretaceous?
2000 ppm in the Triassic?
200-500ppm in the Carboniferous?
10,000-20,000ppm at the Cambrian explosion?