Higher reactivity could explain temperature drop before last ice age
GFZ GeoForschungsZentrum Potsdam, Helmholtz Centre
From time to time, there have been long periods of cooling in Earth’s history. Temperatures had already fallen for more than ten million years before the last ice age began about 2.5 million years ago. At that time the northern hemisphere was covered with massive ice masses and glaciers. A geoscientific paradigm, widespread for over twenty years, explains this cooling with the formation of the large mountain ranges such as the Andes, the Himalayas and the Alps. As a result, more rock weathering has taken place, the paradigm suggests. This in turn removed more carbon dioxide (CO2) from the atmosphere, so that the ‘greenhouse effect’ decreased and the atmosphere cooled. This and other processes eventually led to the ‘ice Age’.
In a new study, Jeremy Caves-Rugenstein from ETH Zurich, Dan Ibarra from Stanford University and Friedhelm von Blanckenburg from the GFZ German Research Centre for Geosciences in Potsdam were able to show that this paradigm cannot be upheld. According to the paper, weathering was constant over the period under consideration. Instead, increased ‘reactivity’ of the land surface has led to a decrease in CO2 in the atmosphere, thus cooling the Earth. The researchers published the results in the journal Nature.
A second look after isotope analysis
The process of rock weathering, and especially the chemical weathering of rocks with carbonic acid, has controlled the Earth’s climate for billions of years. Carbonic acid is produced from CO2 when it dissolves in rainwater. Weathering thus removes CO2 from the Earth’s atmosphere, precisely to the extent that volcanic gases supplied the atmosphere with it. The paradigm that has been widespread so far states that with the formation of the large mountains ranges in the last 15 million years, erosion processes have increased – and with them also the CO2-binding rock weathering. Indeed, geochemical measurements in ocean sediments show that the proportion of CO2 in the atmosphere has strongly decreased during this phase.
“The hypothesis, however, has a big catch,” explains Friedhelm von Blanckenburg of GFZ. “If the atmosphere had actually lost as much CO2 as the weathering created by erosion would have caused, it would hardly have had any CO2 left after less than a million years. All water would have had frozen to ice and life would have had a hard time to survive. But that was not the case.”
That these doubts are justified, was already shown by von Blanckenburg and his colleague Jane Willenbring in a 2010 study, which appeared in Nature likewise. “We used measurements of the rare isotope beryllium-10 produced by cosmic radiation in the Earth’s atmosphere and its ratio to the stable isotope beryllium-9 in ocean sediment to show that the weathering of the land surface had not increased at all,” says Friedhelm von Blanckenburg.
The land’s surface has become more ‘reactive’
In the study published now, Caves-Rugenstein, Ibarra and von Blanckenburg additionally used the data of stable isotopes of the element lithium in ocean sediments as an indicator for the weathering processes. They wanted to find out how, despite constant rock weathering, the amount of CO2 in the atmosphere could have decreased. They entered their data into a computer model of the global carbon cycle.
Indeed, the results of the model showed that the potential of the land surface to weather has increased, but not the speed at which it weathered. The researchers call this potential of weathering the ‘reactivity’ of the land surface. “Reactivity describes how easily chemical compounds or elements take part in a reaction,” explains Friedhelm von Blanckenburg. If there are more non-weathered and therefore more reactive rocks at the surface, these can in total react as extensively chemically with little CO2 in the atmosphere as already heavily weathered rocks would do with a lot of CO2. The decrease in CO2 in the atmosphere, which is responsible for the cooling, can thus be explained without an increased speed of weathering.
“However, a geological process is needed to rejuvenate the land surface and make it more ‘reactive’,” says Friedhelm von Blanckenburg.”This does not necessarily have to be the formation of large mountains. Similarly, tectonic fractures, a small increase in erosion or the exposure of other types of rock may have caused more material with weathering potential to show at the surface. In any case, our new hypothesis must trigger geological rethinking regarding the cooling before the last ice age.”
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“A more reactive surface” would very likely be tied to the amount of tropical volcanism. Lava weathers very fast in a warm climate, which is the reason tropical volcano slopes are often densely inhabited, despite the risks. The soils from recently weathered lava are extremely fertile.
Palermo awaits the next outbreak of vesuvio. With 1 Highway cirkling the city the city can not guarantee to evacuate all citizens. Lava / magma is very fertile soil for vegetable cultivation. Of course the city forbids vegetable cultivation on the vesuvius – the farmers would not have enough forewarning time. So the Italian mafia builds roads up the vesuvius, hides vegetable fields and builds protective walls. The police looks on unconcerned. After all illegal settlers have no right to claim damages substitution.
These guys are inventing a fake mechanism that stops chemical reactions that are known to occur when there is the erosion of limestone in fast running water, from removing CO2 from the atmosphere.
The alternative is that the known laws of chemistry do not change, chemical reactions occur when there is the erosion of limestone in fast running water that will remove CO2.
It is a fact that there was the formation of large mountain ranges in the last 15 million years.
The reason that atmospheric CO2 did not fall to zero in a few million years (which is paradox for the current theory) because there is a massive unaccounted-for source of CO2 that is constantly entering biosphere.
Salby and a dozen other papers have shown that atmospheric CO2 is tracking planetary temperature, not anthropogenic CO2 emissions.
If Salby’s concept is correct there is a massive source of CO2 into the biosphere.
Atmospheric CO2 levels did not fall to zero as the CO2/Water recycling theory, the Late Heavy Bombardment, the Late Comet Bombardment, the Fossil Fuel theory as the explanation for the massive hydrocarbon deposits on the planet that have uranium under them are all incorrect.
There has been a physical breakthrough in geology, the discovery of an active thing, a powerful thing, a thing that explains the abrupt change in the surface geology roughly a billion years ago, the formation of mountains, the formation of deep oceans, that pushes massive amounts of CH4 into the crust.
A few years ago, it was discovered by the computer analysis of reflected seismic waves that there are thousands and thousands of tubes that connect to the crust and appear to originate from the core of the planet.
This is a good example as to how it possible that we are sitting on the weirdest possible breakthrough. This is a show and tell breakthrough that changes the earth, explains how it is possible that mid ocean ridge, earthquakes frequency, all over the planet increased by a factor 300% starting in 1997.
Geology was missing a force to move the tectonic plates. There is no tectonic plate theory. The plates move. Yes. The mystery is what is moving the plates.
Obviously massive things do not move with either a thing pulling them or a thing pushing them.
Twenty years ago there was the discovery of fracturing along ocean ridges. The implications of this discovery was unexplainably not known to the general public. This discovery killed theory that the ocean ridges are somehow being pulled apart by moving mantel below them. The fracturing that occurs cannot be caused be moving mantel and there is on evidence the mantel moves except when it moved by the plates which are moved by a pushing force.
Fracturing requires that a liquid is being pushed into a location where the fracturing occurs. These is exactly analogous to the fracturing of rock for gas or oil recovery. There needs to be a pump, pipe, and liquid that is being pumped into the location.
There are magma cells beyond the earth crust as there are Hadley cells in the atmosphere.
Earth’s crust thin as a postage stamp foil on a baseball –
https://www.google.com/search?client=ms-android-huawei&ei=3gUmXf7LAcL3qwGl_omICw&q=earth+crust+thin+as+a+postage+stamp+foil&oq=earthcrust+thin+as+a+postal+stamp+foil&gs_l=mobile-gws-wiz-serp.
This waltzing, rolling plasma plumes keep the continents in steady motion.
Geological times.
William,
You said, “… it was discovered by the computer analysis of reflected seismic waves that there are thousands and thousands of tubes that connect to the crust and appear to originate from the core of the planet.”
Can you provide a citation for this claim? Considering the immense pressure, even at the base of the crust, it strikes me as being improbable that any “tubes” could remain open.
Hydraulic fracturing is facilitated with high pressure liquid, greater than the lithostatic pressure exerted on the rocks. However, tension can and does create cracks in rocks, including normal faults.
You are presenting some very ‘novel’ ideas that are well outside the mainstream of geologic thinking. Therefore, the burden of proof is on you to substantiate them. However, you don’t even present any citations. You are naive if you think that just making the claims is sufficient to convince anyone you know what you are talking about.
We’re witnessing the Dark Age of academic Earth sciences.
Let me know if this is a correct summation of the article.
Large mountain ranges formed in low latitudes, which then built up huge ice sheets and glaciers.
The ice sheets, being low latitude, increased the albedo of the Earth dramatically, by reflecting sunlight back into space. Therefore, the temperature of the Earth gradually cooled because the level of carbon dioxide was subsequently lowered.
Is that about right?
Also, what happens to the carbon in limestone when it is eroded?
Connecting the dots another way, the uplift of the Himalayas near the equator significantly increased earth’s albedo, lowering temperatures. The ice ages made life less abundant, reducing CO2 concentrations. CO2 levels depend upon aggregate life and decay, and the burning of fossil fuels. The CO2 absorbed by weathering is offset by volcanism.
And, the CO2 absorbed by cooling ocean waters is offset by warming ocean waters.
Albedo is also increased by the foggy mists that arise in forests. Depletion of forests reduces this albedo and reduces aggregate photosynthesis.
“Large mountain ranges formed in low latitudes, which then built up huge ice sheets and glaciers.”
Nope. There has never been a large ice-sheet on the Tibetan plateau. Most winters it isn’t even completely snow-covered. Too dry.