What caused the ice ages?
Short answer: no one really knows although theories abound, and the causes are probably interactions among multiple factors.
I’ve always found the history of earth’s ice ages to be fascinating, from the moment I discovered some maps as a child flipping through my old World Book Encyclopedia (those of you of a certain age will know what I’m talking about). I’ve also always found it to be very very mysterious, and that hasn’t changed.
A few excerpts from the vast number of articles out there [emphasis mine]:
During the present ice age, glaciers have advanced and retreated over 20 times, often blanketing North America with ice. Our climate today is actually a warm interval between these many periods of glaciation. The most recent period of glaciation, which many people think of as the “Ice Age,” was at its height approximately 20,000 years ago.
Although the exact causes for ice ages, and the glacial cycles within them, have not been proven, they are most likely the result of a complicated dynamic interaction between such things as solar output, distance of the Earth from the sun, position and height of the continents, ocean circulation, and the composition of the atmosphere.
Between 52 and 57 million years ago, the Earth was relatively warm. Tropical conditions actually extended all the way into the mid-latitudes (around northern Spain or the central United States for example), polar regions experienced temperate climates, and the difference in temperature between the equator and pole was much smaller than it is today. Indeed it was so warm that trees grew in both the Arctic and Antarctic, and alligators lived in Ellesmere Island at 78 degrees North.
Then earth cooled, then warmed, then cooled…well, you get the idea.
The Earth was once more released from the grip of the big chill between 5 and 3 million years ago, when the sea was much warmer around North America and the Antarctic than it is today. Warm-weather plants grew in Northern Europe where today they cannot survive, and trees grew in Iceland, Greenland, and Canada as far north as 82 degrees North.
We are still in the midst of the third major cooling period that began around 3 million years ago, and its effect can be seen around the world, perhaps even in the development of our own species. Around 2 and a half million years ago, tundra-like conditions took over north-central Europe. Soon thereafter, the once-humid environment of Central China was replaced by harsh continental steppe. And in sub-Saharan Africa, arid and open grasslands expanded, replacing more wooded, wetter environments. Many paleontologists believe that this environmental change is linked to the evolution of humankind.
Plate tectonics are part of the causal explanations as well. But only part.
Another theory explaining these changes in climate involves the opening and closing of gateways for the flow of ocean currents. This theory suggests that the redistribution of heat on the planet by changing ocean circulation can isolate polar regions, cause the growth of ice sheets and sea ice, and increase temperature differences between the equator and the poles.
Also carbon dioxide, but not manmade carbon dioide:
One mechanism proposed as a cause of this decrease in carbon dioxide is that mountain uplift lead to enhanced weathering of silicate rocks, and thus removal of carbon dioxide from the atmosphere.
Here’s another article I think worth quoting [emphasis mine]:
Throughout the Quaternary period, high latitude winters have been cold enough to allow snow to accumulate. It is when the summers are cold, (i.e., summers that occur when the sun is at its farthest point in Earth’s orbit), that the snows of previous winters do not melt completely. When this process continues for centuries, ice sheets begin to form. Finally, the shape of Earth’s orbit also changes. At one extreme, the orbit is more circular, so that each season receives about the same amount of insolation. At the other extreme, the orbital ellipse is stretched longer, exaggerating the differences between seasons. The eccentricity of Earth’s orbit also proceeds through a long cycle, which takes 100,000 years. Major glacial events in the Quaternary have coincided when the phases of axial tilt, precession of equinoxes and eccentricity of orbit are all lined up to give the northern hemisphere the least amount of summer insolation.
See this as well [emphasis mine]:
Today’s ice age most likely began when the land bridge between North and South America (Isthmus of Panama) formed and ended the exchange of tropical water between the Atlantic and Pacific Oceans, significantly altering ocean currents…
Records show that ice ages typically develop slowly, whereas they end more abruptly. Glacials and interglacials within an ice age display this same trend.
On a shorter time scale, global temperatures fluctuate often and rapidly. Various records reveal numerous large, widespread, abrupt climate changes over the past 100,000 years. One of the more recent intriguing findings is the remarkable speed of these changes. Within the incredibly short time span (by geologic standards) of only a few decades or even a few years, global temperatures have fluctuated by as much as 15°F (8°C) or more.
For example, as Earth was emerging out of the last glacial cycle, the warming trend was interrupted 12,800 years ago when temperatures dropped dramatically in only several decades. A mere 1,300 years later, temperatures locally spiked as much as 20°F (11°C) within just several years. Sudden changes like this occurred at least 24 times during the past 100,000 years. In a relative sense, we are in a time of unusually stable temperatures today—how long will it last?
I’m not a scientist, but I can see why at least some scientists buck the current political trends and advance the idea that natural processes account for much or even most of our current tendency towards global warming, and/or climate change in general. My favorite climate scientist, Judith Curry, has this to say on the subject:
She tells me, for example, that between 1910 and 1940, the planet warmed during a climatic episode that resembles our own, down to the degree. The warming can’t be blamed on industry, she argues, because back then, most of the carbon-dioxide emissions from burning fossil fuels were small. In fact, Curry says, “almost half of the warming observed in the twentieth century came about in the first half of the century, before carbon-dioxide emissions became large.” Natural factors thus had to be the cause. None of the climate models used by scientists now working for the United Nations can explain this older trend. Nor can these models explain why the climate suddenly cooled between 1950 and 1970, giving rise to widespread warnings about the onset of a new ice age. According to a group of scientists, we faced an apocalyptic environmental scenario—but the opposite of the current one.
This brings us to why Curry left the world of the academy and government-funded research. “Climatology has become a political party with totalitarian tendencies,” she charges. “If you don’t support the UN consensus on human-caused global warming, if you express the slightest skepticism, you are a ‘climate-change denier,’ a stooge of Donald Trump, a quasi-fascist who must be banned from the scientific community.” These days, the climatology mainstream accepts only data that reinforce its hypothesis that humanity is behind global warming. Those daring to take an interest in possible natural causes of climactic variation—such as solar shifts or the earth’s oscillations—aren’t well regarded in the scientific community, to put it mildly…
What could lead climate scientists to betray the very essence of their calling? The answer, Curry contends: “politics, money, and fame.”…Among climatologists, Curry explains, “a person must not like capitalism or industrial development too much and should favor world government, rather than nations”; think differently, and you’ll find yourself ostracized. “Climatology is becoming an increasingly dubious science, serving a political project,” she complains. In other words, “the policy cart is leading the scientific horse.”
Trump did it. He used his time machine. Impeach the s.o.b! Subpoena his time machine records!
It’s a conspiracy! There were no Ice Ages! It’s the Deep Freeze (before the Deep State) and the Earth is flat! 🙂
I used to tell my best friend who happened to believe in man made climate change to a large degree. that his home in IN was under glaciers and then the climate changed. He is not so dogmatic now, not because of my comments but because it became such a religion.
It’s because all those hominid ancestors of ours stopped using their cars and blew up all the coal-fired electric plants.
The bottom line is that, given our current state of knowledge, and our current ability to model our climate, taking into account all–as if we know today what that “all” consists of–the influences on it, we cannot identify with any certainty each and every one of what appear to be a multitude of forces which apparently cause fluctuations in our climate world-wide, nor can we determine just which ones are the most influential forces in causing these fluctuations.
Just how bogus are some of the models predicting climate disaster?
Well, when I discovered that one of the chief climate models predicting such a climate catastrophe just ignored–didn’t factor in at all–the influence of the oceans on climate–too complicated, don’t ya know–that’s when I realized that something else was going on.
Nor, it currently appears, if we could figure out, identify all the forces at work, could we take any steps to influence them that would be sufficient to make any real difference in their effects on climate, particularly in the short term–say, in the next 30 years or so, when the catastrophe is supposed to hit us.
Thus , when some “scientist,” supposed “expert,” politician, or “activist” says that they “know”–particularly when they state that there is no doubt, and that that absolutely know–for a fact–what is causing climate fluctuation, and they know what draconian steps are needed to be taken to “fix” the problem, you know that they are a fraud.
You know that they have another agenda entirely i.e. using this ginned up Emergency, this “existential threat” as a pretext under which these Leftist politicians, scientists, experts, and activists can seize as much control over every aspect of our society, behaviors, and wealth as they possibly can, using as their excuse preventing catastrophic global warming/climate change.
Snow in the Sierras in mid May. Never mind that sun spots are at an 11 year low.
Far far more recently , speaking in geologic time scales, the causes of the Medieval Warm Period (MWP) and the Little Ice Age, are totally unknown.
The MWP started roughly in the year 950 +/- or so and lasted a few hundred years until about 1250 or so.
This is the time when the Vikings settled Greenland (because it was so warm, Greenland was actually hospitable to farming and animal stock raising) and wine grapes were being cultivated in NORTHERN England .
The MWP ended in about 1300 or so with the commencement of the Little Ice Age (LIA); which lasted until about 1850. (Recall George Washington’s encampment in the FREEZING Valley Forge encampment) as well as art work of Hollanders skating in the canals there). This is also the time that the Viking settlements were abandoned; it was too damn cold for crops and grazing.
NOBODY knows what caused these climatic events nor what caused them to cease. NOBODY.
If CO2 is responsible for warming, from where did the “excess” CO2″ emerge to cause the MWP? Nobody knows.
Where did the CO2 go if it’s paucity “caused” the LIA?
Nobody knows.
And if the historical climate cannot be explained, how can one presume to predict the future climate?
So far the best correlations with climate on earth have been connected with solar activity and to a lesser extent, the rotation of the Milky Way (of which Earth is merely one tiny, tiny rock amongst BILLIONS within the galaxy) .
The entire notion of CO2 – which constitutes 0.04 PER CENT !!! (a TRACE gas in the atmosphere) as being the cause of warming is really a joke. After all, the most abundant green house gas is water vapor – which constitutes well over 95% of ALL green house gases.
The climate change fraud is directly out of the theology of Joseph Goebbels – “repeat a lie often enough and it becomes the truth,” and of Hitler ” the bigger the lie, the more it will be believed.”
By the way, check out the comments of the most zealous global warming proponents; they ADMIT !!!! it’s all a fraud and merely a means to redistribute wealth from , you guessed it, the USA, to the less fortunate nations.
This is why you hear ZERO commentary regarding the HUNDREDS of coal fired plants being constructed in China and India.
The man made global warming thesis; the biggest scientific fraud in the history of the world.
influence of the oceans on climate–too complicated
As I recall, this list also includes: aerosols, clouds, the efficacy of the mislabeled “greenhouse” effect, the very nature of thermodynamics (e.g. energy vs matter), geographical (e.g. mountains) and anthropogenic (e.g. urbanization) features, among the characterization issues, and, of course, the unwieldy nature of their operational space, where even super-super computers are forced to narrow their frame, round, and estimate their calculations. The fact that heating has been statistically insignificant, and the qualifying effects of heat and carbon dioxide are in dispute, are also a cause for skepticism of motives and methods exploited by the proponents of catastrophic anthropogenic global cooling, warming, climate change.
Judith Curry:
Those of us who had family who lived during the Dust Bowl era may have heard of the high temperatures of the 1930s. Bing search: high temperatures 1930s
Another factor possibly relating to climate fluctuation is the work by Svensmark. His interesting idea is that as the sun undergoes it usual 11 year cycle and its longer cycles of activity, those cycles also change the solar magnetic field which expands and contracts. So what? Well, as the sun’s mag field changes so does the flux of incoming cosmic rays; larger solar field, more of those charged particles are deflected. Again, so what? 🙂 Cosmic rays impinging on the atmosphere causes ionization of the atmospheric molecules, which are known to be “seeds” for cloud formation. More clouds, more cooling as the clouds reflect much of the incoming solar radiation.
The actual total solar irradiance (TSI) varies by only a few percent at most and can’t account for the correlation we see between solar activity and global temperature. Svensmark’s idea may be the key. It underwent a lab test at CERN last year but was inconclusive. More data needs to be gathered before his idea has an validity, but it’s intriguing nonetheless.
AND, it’s a natural process. No SUVs needed.
It probably matters a great deal whether or not you have a continent sized landmass at a pole-Antarctica- and a lot of landmass at latitudes greater than 60N or 60S- in present times, northern Eurasia and Canada.
I have always hypothesized that it is a collection of factors that eventually tips the climate in a particular direction- the Summers in the northern/southern landmasses get cooler, which means that not all the snow and ice of the previous Winter melts, which means the albedo of the planet increases slowly, year after year as the Summers get cooler, and the Winters colder- in effect, the ice and snow grow and reflect ever more of the solar energy. The problem is figuring out why this reverses, but, again, it is probably a collection of factors that tip it in the other direction- the Winters get shorter and warmer, the Summers longer and warmer- the ice retreats and the Earth absorbs more of the Sun’s energy converting it to heat.
I remember the dire warnings of the rapidly approaching new ice age that made the cover of Time magazine. Of course it was the fault of the gaia destroying capitalists. I remember thinking at the time, this sounds like BS. The global CO2 warming scam was apparent from the start, a one ring to bind them all under the new world order globalist agenda.
We know a lot, but we also ‘know’ a lot that is not true. And, science is not pristine when mixed with politics. Prince Albert Gore has a private jet to fly around the globe to push his agenda and line his pockets
You don’t need a PhD to recognize a scam when you see one.
It’s all too complicated, except for Marxists, of course.
If all you have is a hammer….
Well, what caused melting of the glaciers? Woolly mammoth farts (and burps).
Thanks, neo!
I love that you write about such a large variety of subjects.
Ages ago I had lots of time to kill in Central Park, NYC. There you can see the surface of these immense mostly buried boulders, which often have these weathered parallel grooves carved onto their top surfaces. An article from 2005 in the NYTimes describes these grooves as “striations” produced by a glacier that covered all of Manhattan.
About 18,000 years ago this glacier began to recede (or had left the island depending on the source). I believe that I had read somewhere that the thickness of ice was once as tall as the Empire State building.
The Times piece closes with the warning that the current global warming could lead to abrupt deglaciation, raising sea levels, interrupting the warm Gulfstream, and thus lead to a new ice age. Got that? At least they were on the same page as Hollywood which released “The Day After Tomorrow” in 2004.
It is no wonder that I give no credence to the Left’s hysteria over our current existential threat de jour of global warming/climate change, and that is because I remember all of the other such “existential threats” to our existence, announced with similar hysteria and cries of doom on the horizon, over the last several decades by various “scientists,” ”experts,” and Leftist “activists”; existential crises that were supposed to doom us all.
Let’s see, there was “the coming Ice Age,” then, we were supposed to face destruction from “overpopulation,” then, we were all to starve as we ran out of food or resources, and along the way—almost as an aside—and thanks mainly to Rachel Carson’s book, “Silent Spring,” we banned DDT.
I am sure that the hundreds of thousand of people in Africa who have died from the Malaria that was on the way to being vitally eliminated (or at least well contained) by the use of DDT were all very grateful for that ban, as are the even greater number of people in Africa and elsewhere in the world who have had or who now suffer from the massively debilitating effects of Malaria.
On this scale of suffering, I guess that it is just a minor nuisance that banning DDT had also led to the rise of the bedbug epidemic here in the U.S.
Make that…” hundreds of thousands”…and…”virtually eliminated”…,
Let’s see — we must cut down on CO2 emissions, which means less plant growth, which means less food production, which means more people starving to death. Got it!
P.S. Has anybody seen an experiment in which somebody took an air-tight tank or chamber and filled it with pre-1950 component atmosphere, then increased the CO2 to today’s levels, to see what happens? I’ve looked all over the Internet (admittedly, my Google-fu is not that great) and can’t find one. And, yes, I do know about Bill Nye and Al Gore’s “experiment,” which is not relevant and fake, anyway.
Mike K:
Good one! 🙂 Hammer and sickle…
Which reminds me of Peter, Paul and Mary singing If I Had a Hammer.
Which reminds me that Mary Travers was a graduate of the Little Red Schoolhouse. With some graduates, the instruction took- such as Victor Navasky and Angela Davis. With some graduates, the instruction wore off, such as Ron Radosh and Elliot Abrams.
One major thing no one talks about is how West Antarctica crashed into East Antarctica around 3 million years ago. West Antarctica used to be part of a small continent in the middle of the Pacific with New Zealand. Around 150 million years ago it split. Part headed west where it ran into the Australian plate. West Antarctica moved southeast until it ran into East Antarctica. On maps that show the continent without ice, you can see the suture line. That crash pushed up mountains. These would have increased precipitation in the form of snow. Also, before the crash, East Antarctica was closer to Australia. They are drifting apart. Australia is moving north. East Antarctica is moving south. So prior to 3 million years ago, the south pole was under water, warmed by currents from the north.
Now, there is a current that circles the globe north of Antarctica. It isolates the continent and keeps it cold. When West Antarctica was drifting south, it kept such a current from flowing, once the ocean south of South America opened up, the current started, and isolated and chilled Antarctica.
Also, prior to 3 million years ago, sea level was 300 feet higher. The Arctic ocean would have covered much Siberia. Rather than a narrow Bering Sea, a shallow ocean would have covered much of the Beringia plain. The larger ocean, and free flow of water over panama, would allow warm water to flow all the way to the North Pole.
We are in an ice age. For 3 million years ice has covered much of the earth. At the start there was a 60,000 year pattern of colder and warmer. “Recently” as the planet cooled further, it has shifted to a 100,000 year pattern. For the past 3 million years, every cycle has plunged the earth colder. If the pattern continued, the earth would be stuck in a permanent maximum glaciation until the continents shifted over millions of years.
Kate on May 15, 2019 at 3:47 pm at 3:47 pm said:
I am positive that Kate is the only one in the known Universe who’s got the straight of it. Thank you, Kate. :>)))
There is that and a lot more on the side of the guys bucking… gals too, but they buck less due to their politics and willingness to let that be their guide..
none of the models they use treat the sun as a source with fluctuating output
why? well ignoring their claims, the easiest point is that if the sun controls it and we cant predict the sun, the whole reasoning to accelerate to a more modern science fiction based fantasy future..
the left kind of likes to push us faster where we are probably going anyway but slower, and then takes credit for it..
spontaneously flaming Tesla is a clue our energy technology is not up to it yet
nor given the battery size, and kind of materials used, is it green by a freaking long shot…
as far as theories go, its right up there with Trofim Lysenko
Snow on Pine,
how about the squares in the cellular automata model being about 400km a side.. problem being the earth is big, and the computing power..
but also, they dont even acknowlege how rounding errors make their itterations more and more wrong from start… not to mention what starting numbers do they use as the odds of them being right are nil, and being off just a little leads to different outcomes in the extremes
I once got in to debate with a self proclaimed “scientist” who argued that changes in plant growth due to changes in climate were not part of any feed back loop. He wanted to insist that plant growth changes were only the effects of climate change but would have nothing to do with future changes in climate….Helps keep the models simpler , I guess.
Living in Puget Sound is instructive in what glaciers leave behind. 10,000 years ago where I’m sitting was under 1000+/- feet of ice. Everywhere you look you can see the remains of old lateral and terminal moraines. Dig into them and you find glacial till. In occasional flat places you will find the remains of morainal lakes. Dig into them and you find fine sediments that often have gravel lenses enclosed.
Go to Alaska and you get to see the glaciers in action. The Mendenhall Glacier, near Juneau, has been retreating for the last fifty years – very visibly so. 213 miles north, the Hubbard Glacier has been growing slowly for the last 50 years. Why the difference? No one knows for sure. There’s a lot we don’t know about weather and even less about large climate changes that have occurred here on Earth. Heck, when climate scientists can tell us exactly why the El Nino – La Nina shifts occur, we might be getting somewhere. Yes, there are theories about El Nino-La Nina, but if we knew the cause, we mighty be able to predict those shifts with some accuracy.
CO2, at 400 parts per million of the atmosphere cannot, by itself, cause global warming. The math doesn’t show it. And the Warmists (Mann, Hansen, Schmidt, Trenberth ,Jones, Briffa, etal) if backed into a corner, will admit that. That’s why they developed their theory of “forcings” – things that help CO2 force the temperature higher. What are those forcings? Aerosols, methane, and the biggie – water vapor – are all programmed into their models. One reason why their models come up with different results is that their values for forcings are “educated guesses.” Thus far the models have been off in predicting the amount of warming that they expected to occur. They’ve been too warm.
At this point the theory of CO2 induced AGW is only that – a THEORY. No solid proof. Yet, we are being asked to abandon the energy sources that have created our modern society. Just say, NO!
Meanwhile, back at the Judith Curry interview.
https://www.city-journal.org/global-warming
Selected comments from the post:
OneMoeurThing jaytrain • 2 months ago
mmille10 Islamaphooey • 2 months ago
gsmullennix • 2 months ago
The comment I quoted has the wrong title for Laframboise’s book, although I do like his version. It might simply be a mistranslation. See the review here.
https://www.forbes.com/sites/jamestaylor/2012/12/14/about-global-warming-united-nations-doubles-down-on-ignorance/#528babf529e3
Lots of good blog-fodder at her website!
https://nofrakkingconsensus.com/
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What was that again about starting out to “write a simple 2-line comment, and an hour and a half later I quit trawling the cyberstacks”??
https://www.thenewneo.com/2019/05/14/whatever-amount-of-time-i-may-think-it-will-take-to-write-a-certain-blog-post/#comment-2434507
I have seen data that suggests that some global warming would produce a net positive for humans on Earth, in that many of the planet’s deserts would become fertile and more habitable.
Also, none of the models have been able to explain the little ice age of the 13th and 14th centuries.
And finally, we know that massive volcanic explosions that send dust into the stratosphere can temporarily cool down the climate. If we felt it wise, we could always recreate this effect with hydrogen fission explosions.
Bottom line: I’m not losing any sleep worrying about it.
From the City Journal link about Curry:
” instead of wasting time on futile treaties and in sterile quarrels, we would do better to prepare ourselves for the consequences of climate change, whether it’s warming or something else. Despite outcries about the proliferation of extreme weather incidents, she points out, hurricanes usually do less damage today than in the past because warning systems and evacuation planning have improved. That suggests the right approach.”
Whether or not global warming is happening is not as important as the results. More droughts, in some areas, often with more fires. More floods, in some areas.
Droughts and floods are subject to technological “fixes” to minimize the problem. Like the NYT in Feb 2018 warned about too much underbrush in CA was a fire disaster waiting to happen — but CA gov’t, pushed by “keep it all natural” enviro fanatics, didn’t take the steps to minimize fire risk in a drought.
More recently in flooding around the Missouri, there were prior plans to use the many man-made diversions of the water in a way to minimize flood risk, and flood damage. These plans were changed so as to help the environment remain “more natural”, putting a higher priority on bio-diversity based theories of limited interventions. Again, the gov’t policies making the flooding worse.
There should be more alarmism about droughts, fires, and floods — and how to minimize damage from them, including more dams, reservoirs, and flood control plains.
If there really WAS a crisis:
a) the UN would be holding all “climate change” meetings by internet video — many companies already do this for real work, not party going – ending “jet travel” for UN workers
b) building more nuclear power generators. India and China are both doing this, and the US should, too.
Casting my mind back to undergraduate geology… I seem to recall a statement by one of my profs that *whenever* there are ice caps, we can consider the Earth to be in an Ice Age – that the “normal” condition is no ice at the poles (possibly it was “no ice occurring naturally anywhere” but I don’t recall that for sure).
I’ve said for years that, particularly since we and our preferred foodstuffs are adapted to a not particularly warm interglacial, what we need to be doing is making sure we and our systems are tough enough for a period of NO ICE.
JJ said: “Living in Puget Sound is instructive in what glaciers leave behind. 10,000 years ago”
Same here in New England. Each spring we have a new crop of rocks in our yard as the frozen ground in winter pushes up the detritus of the what the glaciers left behind. Like weeds we have to pull them, out and then get a new crop the next spring 🙂
Disprove Empirically – Starting with the foundation
What Every Computer Scientist Should Know About Floating-Point Arithmetic by David Goldberg, published in the March, 1991 issue of Computing Surveys
https://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
Floating-Point Computation by Pat Sterbenz, is long out of print….
Rounding Error
This does NOT mean a simulation is wrong…
But it sets limits on certain KINDS of simulation types.
these kinds of models tend to use a cellular automata format.
and THAT format means its an iterative model not a finite (element) model.
this kind of model is most affected by the rounding problem and the BEST you can do is push the issue off in various ways…
i will explain that in my next post.. (and hopefully will be tolerated for those who actually want to learn enough conceptually from some detail and gedanken (a la einstein), to be able to understand what is going on!)
an iterative model is a loop model.. the iterations are ticks of time
now… does time tick? no… time does NOT tick…at least at our size
in fact, depending on whether your on a plane or not, time varies
In an empty universe time has to be infinite IF when you add matter, time slows. 😉
[call that Artfldgrs Theorem of the Void… ]
but for many simulations, and games which are forms of simulations
you need time ticks, so that is one DIMENSION of RESOLUTION (and there are many)
[please note that these terms may or may not match terms in the art, these terms are put forth here so that average people with average vocabulary and so forth can understand the concepts without having to translate a complicated term – both einstein and richard feynman subscribed to the model that if you really understand it, you can share it in common terms]
the fewer ticks, the less accurate, the less time it takes to run, and fewer ‘structural’ errors are injected.
the more ticks, the more accurate, the more time it takes to run, and more ‘structural’ errors are injected.
the above is foundational and often ignored..
its considered esoteric, many people who take up modeling never think of this stuff as its really really bordering on philosphophical, evne more so if you know the physics in detail (like i do) from top to bottom… ie. from Planck sizes to astronomical sizes, to dimensionals…
from what i see, these researchers in global warming are on par with the feminists in the social sciences.
they both produce obvious self serving wrong crap… often VERY wrong crap.
but they create it for power in policy not validity..
with the understanding above…
Round-off Errors and Computer Arithmetic
https://www3.nd.edu/~zxu2/acms40390F15/Lec-1.2.pdf
In a computer model, a memory storage unit “word” is used to store a number.
•A word has only a finite number of bits.
•These facts imply:
1. Only a small set of real numbers (rational numbers) can be accurately represented on computers.
2. (Rounding) errors are inevitable when computer memory is used to represent real, infinite precision numbers.
3. Small rounding errors can be amplified with careless treatment.
do not be surprised that (9.4)10= (1001.0110)2 can not be represented exactly on computers.
so what does a global warming simulation do with this?
well, it doesnt tell the public its limitations, that the more iterations the lower the accuracy
the more detail and more iterations the more errors are injected over the time its run..
this is why we cant do a good weather report from today out to next year
this is a foundational fundemental limit on simulations…
YES… you CAN make your “words” larger… our systems went from 8bits, to 16, to 32, and now we are at 64..
but the larger the word the slower the calculations…
this is why simulations are not easy, each move in benefit costs you someplace else
why?
well, information follows the same laws as conservation of energy and thermodynamics!!!
actually…energy = information
its how we know black holes evaporate
ultimately one of these foundational issues would be enough to limit things
but guess what, there are a lot more and they span the smallest realms of reality to the largest
meaning they are baked into the pie and you deal with them, but cant remove them
[not when time, and energy are limited]
More recently in flooding around the Missouri, there were prior plans to use the many man-made diversions of the water in a way to minimize flood risk, and flood damage. These plans were changed so as to help the environment remain “more natural”, putting a higher priority on bio-diversity based theories of limited interventions. Again, the gov’t policies making the flooding worse.
This happened in the English midlands a few years ago when flood control channels had been allowed to become overgrown for the same reasons.
Next:
Cellular automata models…
Chaos theory…(the REAL butterfly effect)
Demonic heat engines…
Implications…
putting it together….
probably wont reach the end…
lynching is too good for the likes of me..
It ALSO depends on what KIND of simulation…
the kind of simulation that is used in things like design, or graphics, is basically finite modeling and tons of code for figuring out whats in front of, whats in back of, how to render transparency, etc… these models can be VERY accurate, and given the right code behind them, you can actually “run the model”. that is, make an engine or some device, describe the materials, and flows, and actually model the engine running and get some darn good guestimates as to the final outcomes.
what is used in Global Warming and certain other simulations is something called Cellular Automata… which goes all the way back to my youth and Conways game of life.
https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life
this format of simulation has many variations, and not just the simple one that conway came up with, or even ones that degrade to “mathematical beauty”…
in a Global Warming simulation, if you were to write one,
would first start with the grid…
the representation of the thing you want to model.
this is quite equivalent to RESOLUTION..
the more grid squares, the more accurate your model CAN be (but not guaranteed to be)
IF you ask the average person, after explaingin a bit of this, what size they think a grid square should be in a simulation of the earth, as an intuitive concept… most of them actually pick pretty good resolutions… in terms of accuracy.. .
that is, without regard to limits, and the other structural quirks, they tend to pick a good fudge
that most common answer in my journies… 1 meter… some say 1 mile… or 1 kilometer..
they like ones…
the answers they give depend on their perception of the size of the earth in their reality…
so.. 196.9 million mi² [196,900,000]
so your model at 1 mile resolution would have 38,769,610,000,000,000
thats a problem.. your starting to hit something called the Tyrany of Numbers
at least that was what it used to be called before we lost it…
(i still remember it but can never find it)
38 Quadrillion cells in your spreadsheet is a bit much, eh?
so now you start cutting it down..
how far down? well that depends on what resources your talking about..
given the global warming people are not model experts and dont really want such (you can tell cant you? look up who the greatest people in computer modeling and you wont find them flocking to global warming centers)
if you make each grid square 400 miles on a side, your now talking
492,250 X 492,250
so now we are talking 242,310,062,500 grid squares..
if each square held one value, the above is how many 64 bit bytes
you would be using (32 bits integer, 32 bits decimal)
unless you extended the floating point bit size.
the computations follow conways life…
the square in question is computed along with the 8 squares around it to create the next iterative state.
so that means your memory usage just doubled..
one to hold current state, one to hold next state (which then becomes current state)
with one value, as in conways most simple life…
you get 9 values to compute, with the rounding error for all of them
your now about to see how the numbers blow off the table and become insurmountable
so now you have your 64 bit word, your 400 mile grid size, and your two arrays in memory
484,620,125,000 bytes each containing ONE VALUE
lets say that value is temperature… ok… we have the temperature of each square…
while the model is 2D, its actually 3D, the square you are modeling i the real world is not
400×400, and an infinitely think slice
its 400x400x400
now tell me what the temperature of that unit from sea level to 400 miles up is
ok.. so we have to use surface temperature…
we dont have 242,310,062,500 drones to have hover 200 miles up and 400 miles apart.
do we?
your going to find that your going to have to accept many layers of delusion to keep going..
ie. we dont have the computing power yet to do this right…
even IF we have all the data..
even if we could somehow compute the accurate average temperature of a 400 mile unit square
but you say, the planet is not smooth like a marble it has many heights and levels and mountains and more..
well, if your cubes are 400 miles on a side, your planet is a marble thats real smooth
8,850 meters is the height of everets… thats just above 1.3 miles with 398.7 to go…
but you say, temperature is not enough, you need more.
yeah, you need to add things like temperature, gas make up, flow, and so on
and the models grow like rube goldberg devices…
and they dont work, because their basis theory of fixing the error propagations of the various limits is fake
YES FAKE
They dont tell you, but if you program simulations, and are good, you would notice that their idea of fixing this is to keep aligning the data of the past till the model works and so the data in the future is right
might work for a finite element model (probably would)
but not this form of model…
so… now… lets say your going to add this.. and now you have about 1k of variables..
484,620,125,000 X 1000 = 484,620,125,000,000
and if you just Add them up and average them…
thats 8008 operations per square.
thats 3,880,837,961,000,000,000 operations, each with rounding errors and for one iteration of averaging.
not more complicated than that.
if you had one processor running at 10gig FPO a second…
it would take 388083796 seconds to do the calculations (while ignoring writing it to memory takes even longer)
6468063 mins
107801 hours
4491 days
12 years
so on one computer that fast, it will take 12 years to do one iteration..
if you need a thousand of them… you can take 1200 years to see the result
oh, but of course you want to run this many more times, right?
good thing cellular automata are highly able to be paralleled…
but note… the next question is.. how big a time tick?
1 measure a day? no, that ignores night vs day difference
2 ticks..
how about 1 second? 86400 units for a day, 31536000 for a year
and we are going to do what, 100 years?
and again… we hit a wall in computation time and so on..
and it gets WORSE..
next.. if people want to hear it…
understanding chaos theory makes their work even more impossible given conditions
physics guy: “Each spring we have a new crop of rocks in our yard as the frozen ground in winter pushes up the detritus of the what the glaciers left behind.”
Yep. We call them glacial potatoes because they are well-rounded (from glacial polishing) and mostly about the size of potatoes.:-)
“more natural”: The classic assumption that things, left to their natural order, result in good outcomes for living creatures. This is not true. Things happen in the universe for any number of reasons, not one of which is because anyone or anything has personal or emotional stake in providing good outcomes.
What makes humans unique among life forms on this planet is the ability to take large and meaningful actions to thwart the natural order. Otherwise, we would be subject to the same constant waxings and wanings (of temperatures, of rain, of rivers, lakes and oceans, of places free of volcanic activity or mile-high glaciers) and random cataclysms that make life miserable and short for most creatures, at most times, in the planet’s history.
Two inputs controlling the major swings between “hothouse” and “icehouse” climate regimes. The Milankovitch cycles (variation in the Earth’s eccentricity, axial tilt, precession) and plate tectonics (impeding oceanic circulation between poles and equator). Lots of other factors need to be worked out, yet.