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.”
###
They’ve got a computer model of the carbon cycle? That works over geological time? Wow.
Potsdam is German for damned potty.
So no rain no weathering.
The scientific literature I have read states that the ice core record shows that atmospheric CO2 changes lags temperature changes by ~400 to ~800 years.
I proved in January 2008 that atmospheric CO2 changes lag temperature changes by ~9 months in the modern data record, on a shorter time cycle.
However these scientists seem to believe that atmospheric CO2 is the primary driver of Earth’s temperature.
It’s 430am here and I’m going back to sleep. Maybe this will make sense when I reawaken. Right now, it’s like one of those crazy dreams where the future causes the past.
There is this concept called precedence. Can the future cause the past? Even at 430am, it seems improbable.
No atmospheric CO2 is the primary driver of Earth’s temperature = No funding.
Yes, it is absolutely amazing the hurdles they will jump through to hypothesise that CO2 controls every aspect of Earths climate. It is farcical.
“They entered their data into a computer model of the global carbon cycle.” At this point I stopped reading.
CO2 *does* lead temperature, but only along a narrow corridor one molecule wide straddling the Pacific International Dateline where Yesterday meets Tomorrow!
Years ago I became stuck like a pig on the TEMP/CO2 lead/lag causation issue and have remained there ever since. These magical amplifying feedback claims are just too great a hurdle to jump.
Good one, Allan. I had the same thought when I read this article. The premise that CO2 drives the temperature is not questioned.
That is the quadrature phase shift between CO2 and d/dt(CO2), as I seem to recall you pointed out: d/dt(CO2) matches temperature better than CO2(t) vs SST(t).
That shows that , at least the sub-decadal changes are SST driving CO2 and not the other way around. Since the proxy data shows a similar relationship, they need to stop messing around with these tortured, speculative hypotheses attempting to prove everything which ever happended was cause by CO2.
A Milton Jones joke I heard recently:
1895 – HG Wells publishes The Time Machine
1896 – HG Wells writes The Time Machine
2315 – HG Wells is born
Can you quote the scientists and the publications?
I know climate science and nowhere is there a scientific valid publication that states that CO2 drives temperature, rather there only is evidence that CO2 and temperature are intrinsically linked, which is very different from what you claimed.
I’d suggest you to learn about feedback effects, both positive and negative, before you post more shit.
“Temperatures had already fallen for more than ten million years before the last ice age began about 2.5 million years ago.”
This was new to me. I thought that the last ice age began about 100 thousand years ago.
Perhaps it should be the period of regular ice ages.
We are within an interglacial period in an ice age, which consists of several glacial/interglacial cycles.
I think you are misunderstanding the definitions of the terms. We are currently in an ‘ice age’ that began aout 2.5 million years ago. This ice age consists of short warm periods called ‘interglacials’ and much longer cold periods called ‘glacials’. The last glacial period started over 100,000 years ago and ended about 12,000 years ago with the onset of our current warm, interglacial period we call the Holocene.
Lay people often refer to glacial periods as ice-ages, and consequently believe that we are no longer in an ice age. Unfortunately, we are still very much in an ice age. It is just a matter of time before the next glacial period begins.
Interglacial periods begin rather abruptly, but the end very gradually. The Holocene hit its temperature peak about 2-3 thousand years after it started. This period is called the Holocene Climate Optimum, because it was named more than 30 years ago, when everyone knew that warmer is better. Since the Optimum, the planet has been slowly cooling. 200 years ago, the atmospheric temperature dropped to its coldest level since the last glacial period.
Will the burning of fossil fuels delay the onset of the next glacial period? No one knows, but I pray that it does!
As far as I’m concerned, an interglacial period begins when the glaciers start melting …… and thus the current interglacial began at around 21,000 yBP,
http://cdn.antarcticglaciers.org/wp-content/uploads/2012/06/Post-Glacial_Sea_Level_rise2.png
Now the Holocene Period ….. or Holocene Interglacial which some refer to it as, …… only comprises the past 11,000 years of the aforesaid 21,000 year interglacial period.
And given the fact that the aforesaid 11,000 year Holocene Period is also, so far, the “warmest” part of the current interglacial it is also denoted as being the “Climate Optimum”.
“As far as I’m concerned, an interglacial period begins when the glaciers start melting …… and thus the current interglacial began at around 21,000 yBP”
I think you are pretty alone with that definition. In that case you could just as well say that it started 64,000 y BP when the first major stadial of the last glacial cycle (MIS 4) started melting.
The current interglacial started, quite abruptly, 11,600 years ago when temperatures rose about 5 degrees in just 50 years, from an ice age climate to considerably warmer than at present.
tty – July 6, 2019 at 11:28 am
Now tty ….. after you graduated from your formal schooling you really should have started thinking for yourself. You have already gotten your “grades” so there is no reason to be mimicking your past Teachers and Professors because they cannot “change-your-grade” after the fact.
And 1st of all, tty, ….. a 5 degree temperature increase in 50 years …. does not jump-start an interglacial period.
“DUH”, iffen a 5 degree temperature increase occurred during the next 50 years, ….. would the earth then be in an Interglacial-interglacial Period?
And tty, by 11,600 yBP, glacial melting had caused sea levels to rise by 80 meters (263 feet), …. from 130m @ 21K yBP to 50m @ 11.6K yBP, ….. as denoted on the above cited PGSLR graph.
And with a tremendous surge in sea level rise (Meltwater Pulse 1A) @ 15.5K yBP, ….. there just had to be one hellava sudden temperature increase, ……. RIGHT?
Surely it wasn’t caused by the FSM, ……. RIGHT?
And the next thing is, …. tty, ….. iffen those damn glaciers began seriously melting @ 21K yBP, then it should be pretty damn obvious that the current interglacial had begun.
And last but not least, …. tty, ….. to get a better perspective of what you are talking about, take a “look-see” at this conjoined graph of Post glacial sea level rise and Holocene temperature variations on which you can easily see that temperature increases prior to 11.6K yBP were actually quicker and surely warmer (hotter) than they were after 11.6K yBP.
Of course, you can always claim those two (2) proxy graphs are FUBAR.
Cheers
Here is the best reconstruction of the melting of the Eurasian Ice-sheet:
https://www.researchgate.net/publication/282726844_The_last_Eurasian_ice_sheets_-_a_chronological_database_and_time-slice_reconstruction_DATED-1
You will notice that at 21,000 BP the ice sheet was still growing, indeed on the eastern flank it did not reach its maximum extension until 18,000 BP. A bit odd that during an interglacial, eh?
And an interglacial starts when the climate becomes interglacial. Which didn’t happen until the end of the Younger Dryas 11,600 years ago. I recommend that you read up on the Late Glacial Interstadial (Bölling-Alleröd) and Younger Dryas.
tty – July 7, 2019 at 9:09 am
tty, ….. that is not what the abstract of your cited reference states, …… to wit:
Read it again, ….. “…. attained its maximum extent at c. 21 ka.
I am reasonably sure that ….. c. 21 ka ….. is equal to my stated …. 21,000 BP.
Unfortunately, “ice age” is used in the vernacular to be synonymous with “glaciation” or “glacial epoch”. The current ice age began 2.6 million year ago, with glacial-interglacial cycles of about 100,000 years. We’re currently in an interglacial within a much longer ice age.
Sorry but no. The glacial cycles were only 41,000 years until about 800,000 years ago when there was a relatively fast changeover to 80,000-120,000 year cycles with a much greater amplitude. Just how and why this happened is one of the great unsolved problems of paleolclimatology.
http://opengeology.org/textbook/wp-content/uploads/2017/01/15.3-oxygen-isotope-record-Lisiecki-and-Raymo-2005-1024×768.jpg
It should be 50 million years, but then 50 is more than 10:
And 2.5 million years is when major regular ice-ages started in the northern hemisphere.
Are they saying that we will have less and less CO2 in he atmosphere,
despite being told there is more and more of the stuff.
Sound to me that to be on the safe side and to avoid such a calamity as a Ice
Age, we need even more CO2. Now that is a preventable principal I can
believe in.
MJE VK5ELL
“Higher reactivity could explain temperature drop before last ice age.”
Lets give this a little perspective, we’re talking about a temperature drop of maybe 6 or 7C over 15 million years.
Kind of makes the human caused rise look fairly abrupt.
Loydo, there is no human caused rise in temperature.
There certainly IS human caused temperature increases, and Mann is responsible without a doubt
Grasping at straws again I see. Typical.
Loydo,
A 6 or 7C rise is what ends a glacial period starting an interglacial, like the current Holocene.
A few tenths of a degree over 200 years is abrupt?
PS: Most of that warming occurred prior to the “big” runup in CO2, so it couldn’t have been man caused.
Nor is there any evidence that much if any of the warming since then was caused by man either.
Comparing proxies with resolution measuring millennia or more, to yearly data records is invalid, but it’s all the alarmists got.
There could easily have been temperature movements 10 times what the “adjusted” data shows for the last 200 years, but it wouldn’t show up due to the resolution of the proxies.
So your claim is completely unsupportable.
It’s CO2 “science”, so anything’s possible.
The CO2 hypothesis of climate change is infecting Geology. The unsupported assumption is evident:
– removed more carbon dioxide (CO2) from the atmosphere, so that the ‘greenhouse effect’ decreased and the atmosphere cooled.
– The decrease in CO2 in the atmosphere, which is responsible for the cooling
In science one has to be very careful with the underlying assumptions as they bypass the scientific method and usually lead to wrong conclusions.
There is no correlation between CO2 and temperature over the past 50 million years. Both decreased but they did it a different times and rates.
Global temperature decreased a lot over the past 15 million of years, a time when CO2 proxies indicate CO2 levels were not decreasing and already at 300-400 ppm.
So a decrease in CO2 levels could not have been responsible for the cooling unless we accept a delay of the order of 10 million years between the decrease in CO2 and the decrease in temperature. Not what alarmists would like to hear.
“Temperatures had already fallen for more than ten million years before the last ice age began about 2.5 million years ago. ”
So those who believe in global warming should realise we live in an ice age today what historically is not the ‘normal’ climate for this planet and that CO2 used to be much higher without being able to provoke a runaway greenhouse effect.
That argument has little value. We are in an ice age, sure, but coming out of the ice age would cause us a lot of troubles, as we are adapted to the present situation, not the Eocene conditions. So significant warming or significant cooling are both detrimental to us. The problem with being adapted is that the best situation is the one we are in. Through history some cities at the seashore ended up land locked or underwater due to isostatic changes. Those changes weren’t positive.
What could the actual problems be? I have a little problem believing that we can not adapt further to match future conditions barring a return to an snow ball earth. A few degrees temperature rise seems inconsequential.
Agree. There are far more real & immediate problems to deal with.
The actual placement of about 1/4 of global population would be underwater if the cryosphere melts. There were no polar ice sheets during the Eocene. Significant warming would result also on a lot of ecological changes, not all of them positive.
The idea that we would do equally well moving to a non-Ice age condition is unsupported. Too many unknowns. What we do know is that we are well adapted to the present situation, and adaptation to different conditions does not necessarily mean improvement.
It would not be catostrophic, and we would adapt, a glaciation on the other hand would be catostrophic.
The idea that we would suffer dire consequences is also unsupported as is the idea that we might return to non ice age conditions within a time scale that is meaningful.
It would take something like 10,000 years for the Greenland glaciers to melt. Antarctica is even better protected from melting due to the extreme cold over most of the continent.
If you are trying to argue that humans couldn’t cope with a change that takes over 10,000 years to manifest, then you know nothing about humanity.
I guess some people have trouble reading what others actually say and prefer to raise strawman arguments about catastrophes and inability to cope.
Being able to cope doesn’t mean you are better off, and being worse doesn’t mean it is a catastrophe. Vikings were able to cope and adapt to the Little Ice Age in Iceland, but they didn’t have a great time doing it as their population decreased to almost half.
If the world were to continue warming at about 1°C per century for several centuries that would pose some troubles, and while I have no doubt we would adapt, it is not a sure thing that we would be better off than if the present condition remains stable. After all we are already adapted to the present climate.
So 12,000 years ago humans would have been better of if the condition would have remained stable. Perhaps you’re right. No New York No Canada No Scotland, Norway, Sweden etc. They had prospered in those conditions almost 90,000 years.
Buildings only last a few decades. As they wear out, replace them with buildings further inland.
No problem.
The idea that mankind would suffer if the planet warmed a few degrees is so absurd that calling it ludicrous would be a compliment.
There is no downside to the small amount of warming that CO2 might be able to cause.
Just imagine a daily forecast for 78° to 88°degrees instead of 75° to 85° degrees, simply terrifying….
This statement FTA makes zero sense, in fact it is utter nonsense:
“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.”
Chemical weathering only affects a subset of rocks – limestone. CO2 in water has virtually zero effect on silicates like granite, gneiss, and sandstone, which make up the vast majority of exposed rocks and most of earth’s crust. Limestone was not an original part of the earth’s actual crust, since it comes only from deposits of sea life accumulating over eons of time. Indeed, limestone (and its weathering) is not “billions of years old” as this article claims, since limestone is made up of the skeletal remains of marine mammals, the oldest of which are approx. 500 million years old.
Limestone that is exposed may act as a sort of “sink” for carbon, or “reactivity” is increased, as these authors claim, but the sheer volumes could never ever serve as the thermostat for the planet, even if CO2 itself were the chief cause of temperature fluctuations, which it is not.
This is bad science, fake science. It has no basis in logic or fact.
CO2 had to form that rock before it weathered that rock; kind of like I was for it before I was against it.
Duane,
The reaction with a weak acid and a silicate is certainly not as dramatic as with a carbonate, but it does proceed at a ‘geologic’ pace. Read Konrad Krauskopf’s book on geochemistry. Go in the field and look at the surface of ultra/mafic rocks, particularly those rich in calcium-bearing feldspars or olivine.
All rocks weather.
But the dramatic weathering that the authors describe as the earth’s “thermostat” is carbonic acid reacting with limestone deposits. Again, that is only a small percentage of total rock weathering. The biggest factor by far in removing CO2 from the atmosphere involves simple dissolving of CO2 gas in ocean water. which is accelerated when oceans cool, and decelerated when oceans warm and offgas excess CO2 to the atmosphere. Once dissolved in ocean water, it is taken by sea life, incorporated into shells and bones and teeth and coral reef, and eventually deposited on the ocean floor where it eventually is converted to limestone.
The weathering of silicates is a different process – with mechanical erosion, mechanical abrasion, and freeze-thaw cycles being the predominant processes for silicates.
As noted elsewhere, there is both mechanical weathering (predominant at high elevations or during glaciations) and chemical weathering. As remarked by Krauskopf (1967):
“One can show, indeed, by leaving water in contact with finely ground feldspar for hours or days, that the solution becomes faintly alkaline and that it contains a little K+, alumina, and silica; …” (p. 115) and,
“As a third line of defense we can turn to silicate minerals other than the clay minerals: feldspars, pyroxenes, amphiboles. These are subject to slow acid attack, breaking down to form silica and kaolinite and contributing their cations to solution.” (p. 626)
That’s embarrassing – make Feldspat <- – feldspar
Duane,
You said, ” Indeed, limestone (and its weathering) is not “billions of years old” as this article claims, since limestone is made up of the skeletal remains of marine mammals, the oldest of which are approx. 500 million years old.”
Actually, calcium carbonate can precipitate from warm seas, such as happens today in the Bahamas. So, the abundance of limestone was probably less than today, but surely there were lime muds during the Precambrian.
Also, the marine animals you refer to are not mammals! They arn’t even marsupials.
I meant to write “animals” not mammals.
They have to read the papers if Shaviv and Veitzer, it’s well explained there, even CO2 and heavy oxgene is explained, add Svensmark and all is ok 😀
Is CO2 really the only show in town? The Sun, the oceans, continental drift, ocean currents, atmospheric currents all seem to count for naught in explaining how global average temperatures go up and down. H2O is the biggest temperature mass storage and will cool as well as warm. The following graphic of temperature over the last 70 million years show a marked down turn around 5 million years ago, right about the time the Med flooded.
“Today’s scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality.” – Tesla
” Beware of false knowledge; it is more dangerous than ignorance” – G B Shaw
“A government that robs Peter to pay Paul can always depend on the support of Paul’ – G B Shaw
‘There is nothing more dangerous than the conscience of a bigot’ – G B Shaw
I love the Tesla quote. It is particularly applicable in today’s world, where computer models (massive collections of equations) are said to be modern Oracles.
If Tesla were alive today, he probably would have said ““Today’s scientists have substituted computer models for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality.”
That sums up modern climate science in a single sentence!
The explanation I heard is simpler and makes a lot more sense. It is based precisely on the things you mentioned.
As the continents moved ocean currents changes and this led to a cooling of the oceans. The atmosphere can never get far away from the temperature base provided by the oceans. Hence, the atmosphere cooled right along with the oceans.
The cooler oceans also absorb more CO2 which is why that level dropped over the same time period. Both the air temperature and the CO2 levels are the result of cooling oceans driven by plate tectonics.
I’m guessing that the closing of the Isthmus of Panama several million years ago affected ocean circulation and had something to do with the ice ages.
Then the cooling seas pulled CO2 out of the atmosphere.
The whole study is predicated on CO2 being the temp control-knob. That’s never been substantiated.
Can anyone say we don’t know?
We don’t know
We don’t know. Leaving us the chance we have lots of
https://www.pinterest.com/juleschubert/%C3%BC-ei-umh%C3%A4keln/
to unpack.
The Potsdam Institute is synonymous with bad science and bad scientists. Edenhofer (actually an economist), Schellnhuber, and Rahmsdorf – to name but a few.
Contorted and absurd logic, just right for the new Nature.
How about this for an explanation?
Not knowing much physical chemistry appears to be one of the qualifications for being a climate scientist.
“The last ice age” in everyday speech usually substitutes for “the last glacial period” i.e. the Wisconsin or (if you prefer) the Würm glacial stage. What the news-release writer should have said is, of course, “the current ice age” – but that would hardly be consistent with the message that we are currently experiencing unprecedented® warming. It might sow the seeds of doubt in the mind of the reader, and we can’t have that, can we?
There are several possible answers to when “the last ice age” started, but 2.5 MA is not one of them.
1. c. 35 million years ago when the first continent-wide glaciation of Antarctica (Oi-1) ushered in the current “ice-house” climate
2. c. 14 million years ago when Antarctica froze over permanently
3. c. 117,000 years ago when the latest (not last) glacial cycle started.
What happened 2.5 million years ago was that large scale lowland glaciation in the northern hemisphere became frequent and has since the happened every glacial cycle as far as we know. It had however actually already happened once or twice during the Pliocene.
Another example of the satanic CO2 Meme addling the minds of purported scientists.
When you remember that CO2 lags temperature you realise what nonsense this paper is.
“They wanted to find out how, despite constant rock weathering, the amount of CO2 in the atmosphere could have decreased.”
How about considering the little known fact (to born-again climatologists) that the solubility of CO2 in water is inversely proportional to its temperature? That is, as the oceans cooled for 10 million years, more CO2 from the atmosphere was able to dissolve in the sea water, transferring it from the atmosphere to the hydrosphere.
“They wanted to find out how, despite constant rock weathering, the amount of CO2 in the atmosphere could have decreased.“.
Duh. CO2 decreased because the temperature decreased.
[With apologies to all the other commenters who have said this already in various different ways].
Mike Jonas – July 6, 2019 at 9:25 am
In most cases, “YES”, …… but the Cretaceous Period is an exception. Temps increased, CO2 decreased.
And it was the “decreasing” CO2 during the Cretaceous Period that caused the demise of the dinosaurs. And the proof is in the proxy graph cited below.
CO2 began decreasing at 144 MyBP, …… which forced the decrease in “green-growing” biomass, ….. which forced the starvation of the herbivore dinosaurs, ……. which in turn forced the starvation of the predator dinosaurs ……. and they all disappeared from the fossil record at 66 MyBP, (without any help from an asteroid strike)
The Age of the Dinosaurs – 252 million yBP to about 66 million yBP, ……. as defined on this Atmospheric CO2 and Global Temperature proxy graph, …. began with an increase in CO2 and terminated because of a decrease in CO2, to wit:
All animal species react the same. Their body size and their population numbers INCREASES during the food getting “good” time, ……. and their population numbers DECREASE during the starvation “bad” times.
Supercontinents and the Pacific Northwest
https://youtu.be/cg69QbPxHsA
This “paradigm” indeed got a lot of traction among the “CO2 and only CO2 drives climate” fraternity. It’s been announced with fanfare more than a few times lately.
But it hasn’t really succeeded in displacing the theory that plate tectonics, the configuration of continents and patterns of ocean circulation caused the really big changes in climate during Cenozoic times. Opening of the channel between South America and Antarctica led to the Southern Ocean circular current, isolating Antarctica and allowing it to start forming an ice cap, which gave rise to “Temperatures had already fallen for more than ten million years“.
Then the closing of the gap between North and South America, the formation of the Panama Isthmus, sent a lot of warm water into the north Atlantic, leading to more high-latitude evaporation and precipitation. Because it was already a lot colder, this allowed the big Northern Hemisphere ice caps to form. And here we are today.
This two-stage explanation of why we’re in the current ice age has the advantage of linking specific and singular events in earth history with specific and singular events in earth climate, and reasonably logical explanations for how and why they are linked as cause and effect (“singular” does not equal “unique” as similar events probably led to previous glaciations).
It gets complicated in detail, requiring us to explain why the SH ice cap is stable over the long term, and why the NH ice cap is not. Probably, the NH ice cap keeps expanding till the sea level falls by 120 metres (which we know) and this would cut off much of its fresh snow supply, leading it to stop growing, lose a lot of albedo, and start melting. Inherent instability of the NH ice cap is probably what makes it susceptible to the biggest orbital changes, i.e. the Milankovitch cycle (and multiples thereof, thanks Javier for that). But you can think it all through and it holds together as good theories tend to do.
These authors, by contrast, have (so they claim) debunked the “mountain building causes more erosion, which causes more CO2 to leave the atmosphere for the oceans, which makes it colder” hypothesis. But, being good climate scientists, they need to link something to reduced atmospheric CO2 to explain the ice age. And they have come up with “soil reactivity”, a concept of such stunning fuzziness that it rivals the use of god to explain evolution by those who don’t like natural selection and genetic drift.
The article doesn’t have a link to the paper (which would be paywalled anyway) but I suspect that they don’t actually have any new factual observations; they “entered their data into a computer model of the global carbon cycle” – which basically says it all. Models, again.
“Could explain.” Speculation. Business – sorry, science – as usual.
“Could explain.” Speculation. Business – sorry, science – as usual.
This theory that erosion of mountain chains draws down CO2 was killed decades ago by Greg Retallack who pointed out that erosion of mountains is almost wholly mechanical, and that the degree of weathering of sediments in the Bay of Bengal went down drastically as the Himalayas rose.
It is erosion in lowland areas that is predominantly chemical, that is where you find weathered soils with little silicates left.
“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.