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  #21  
Old 22-10-2019, 07:38 AM
Dove (Alan)
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[QUOTE=bojan;1450561]Yep...

Can I offer some badly needed education on precession, see here:
https://en.wikipedia.org/wiki/Precession

Yes Bojan I agree, on the presumption that some contributors may not be familiar with all details of the precession of the equinoxes, a fundamental factor of planetary motion.

For example, precession of the equinoxes is a demonstration that Earth's orbit is a spiral motion that progresses the orbit about the plane of the ecliptic and the North pole cycling about the pole of the ecliptic. This spiral orbital motion of our. planet seems not to be fully recognised.
Alan D.
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  #22  
Old 22-10-2019, 08:45 AM
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Alan,

It is essential to understand the mathematical and physical basics before going any further with this discussion.
Gary's reply is a good start...
Precession of equinoxes is well undersood phenomenon...

Spiral orbits are one of the effects of GR, see here:
https://en.wikipedia.org/wiki/Tests_...ral_relativity
In practice, those effects could be disregarded as insignificant when Earth orbit around our star is concerned.
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  #23  
Old 22-10-2019, 12:32 PM
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Sunfish (Ray)
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+1 for Gary and Bojan
Thanks for that.

Like Charlie Browns football , what appears to be a question aimed at science discussion winds up being not there at all.
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  #24  
Old 25-10-2019, 08:51 AM
JohnF (John)
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Originally Posted by Dove View Post
Hello to all.

I address my argument to those who agree with the scientific premise that there is no such thing as perpetual motion, in order that we can proceed to look at some facts concerning the motion of our planet. Namely the misconception in astronomy that earth's angle of obliquity is unchanging and earth will forever remain wobbling around 23.5 degrees due to the perturbations of our sister planets.

Those friends who believe that there is such a thing as perpetual motion, can rest content in the notion that earth will exist forever wobbling around 23.5 degrees obliquity. Cheers Alan.
It is probable that once the earth was not wobbling at 23.5 degrees. Fossils of tropical animals are found at both poles, that is what is now our Polar regions were once warm. and the poles have change their position many times in the past according to the fossil record.

So that is one thing that possibly proves that we were not always at 23.5 degrees.
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  #25  
Old 25-10-2019, 09:04 AM
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....So that is one thing that possibly proves that we were not always at 23.5 degrees.
It only proves the places where today's rotational poles are were not always at the rotational poles...
Also, continents are migrating independetly of Earth rotation and/or precession.
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  #26  
Old 25-10-2019, 09:59 AM
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It is probable that once the earth was not wobbling at 23.5 degrees. Fossils of tropical animals are found at both poles, that is what is now our Polar regions were once warm. and the poles have change their position many times in the past according to the fossil record.

So that is one thing that possibly proves that we were not always at 23.5 degrees.
It's more than probable: It's certain - (Pr=1) (as much as science can ever be).

The evidence in the scientific literature is clear on the fact that the Earth's current 23.5 degree angle of tilt (obliquity) varies over something like a 40,000 year cycle by a few degrees (±1 or so degrees). There are also other orbital changes (on much longer time scales): changes in the eccentricity of the Earth's orbit around the Sun and precession of its rotational axis.

These are all well documented variations in the earth's orbital parameters and were brilliantly pulled together by Mulitin Milakovitch, a Serbian mathematician to help explain climate change and the coming and goings of the ice ages (and as a reasonable logical extension many of the changes in between).

Best
JA

Last edited by JA; 25-10-2019 at 10:10 AM.
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  #27  
Old 25-10-2019, 11:13 AM
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Fossils from polar regions demonstrate plate tectonics and continental drift (with a bit of geological scale climate & greenhouse gas change thrown in), *not* that Earth tilted wildly on its axis any more than we very well understand from orbital mechanics (e.g. Milankovitch cycles). The astronomical year has not in human times been 360 days either (hard to believe this came up at a reasonably scientific site) - those who think so need to learn about intercalation and intercalary months that were present in ancient calendars to allow a 360-day calendar (an extremely pretty round number with opportunity for subdivision) to be repeatedly recalibrated to the ~365.25 day astronomical year.

None of the Solar System's orbital mechanics has anything to do with the laughable pseudoscience notion of 'perpetual motion', which generally involves magicking up some free energy to maintain an otherwise decaying system. XKCD visited this just the other day. Physics is mean...
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  #28  
Old 25-10-2019, 11:45 AM
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Fossils from polar regions demonstrate plate tectonics and continental drift (with a bit of geological scale climate & greenhouse gas change thrown in), *not* that Earth tilted wildly on its axis any more than we very well understand from orbital mechanics (e.g. Milankovitch cycles).
Hi Andy,

And one of course doesn't have to go far here in Sydney to see wonderful examples of continental drift.

Large swaths of Sydney are built upon Haweksbury River sandstone.

Some of it is most dramatically seen through the cuttings of the M1
(previously F3) Freeway between Sydney and the Central Coast.

Very close to where I am right now.

Douglas Mawson I recollect was one of the first to recognize the
sandstones he saw in Antarctica were "Hawkesbury River" sandstone.

All when Australia and Antarctica were all part of Gondwanaland and
"Sydney" was much closer to the south pole.

Quote:
Originally Posted by http://www.adderley.net.au/geology/exhibition/
The Hawkesbury Sandstone is a Triassic sedimentary quartzose sandstone
(mainly quartz) with a smaller proportion of feldspar, clay,
and iron compounds such as siderite (FeCO3).
It was formed from the sands which came from Antarctica
about 200 million years ago, carried by a vast river system.
Over millions of years these sands were consolidated into sandstone
up to 50 metres thick on the peninsula.
Hawkesbury Sandstone contains minor shale beds rich in fossils.
http://www.adderley.net.au/geology/e.../04_02_12.html
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  #29  
Old 25-10-2019, 02:41 PM
Dove (Alan)
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Quote:
Originally Posted by JA View Post
It's more than probable: It's certain - (Pr=1) (as much as science can ever be).


JA
Hello John F,

Yes, that is right. the obliquity has been known to be reducing regularly for the last 2000 years and we know how important this angle is to our climate. The current theory is as we know Milankovitch’s but it only offers an explanation of some 2.3 degrees wobble and some varying eccentricity changing the obliquity.

This theory puts a restriction on all astronomers and geologists to within a very narrow range to explain the mysteries of great changes of climate in the past. These past changes in climate call for an explanation covering a greater range of obliquity.

As Bojan rightly suggests, we need to look deeper into the subject. For example I suggest we start by looking at the motion of our planet. The earth is travelling about the Sun. So I ask all contributors, is it travelling in a circle or a spiral? We can all answer this definitively I am sure. It is an important point to commence the argument.

Alan D.
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  #30  
Old 25-10-2019, 03:55 PM
JohnF (John)
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Quote:
Originally Posted by Dove View Post
Hello John F,

Yes, that is right. the obliquity has been known to be reducing regularly for the last 2000 years and we know how important this angle is to our climate. The current theory is as we know Milankovitch’s but it only offers an explanation of some 2.3 degrees wobble and some varying eccentricity changing the obliquity.

This theory puts a restriction on all astronomers and geologists to within a very narrow range to explain the mysteries of great changes of climate in the past. These past changes in climate call for an explanation covering a greater range of obliquity.

As Bojan rightly suggests, we need to look deeper into the subject. For example I suggest we start by looking at the motion of our planet. The earth is travelling about the Sun. So I ask all contributors, is it travelling in a circle or a spiral? We can all answer this definitively I am sure. It is an important point to commence the argument.

Alan D.
Well I had read many years ago that the earth travels in an Elipse shape. Not sure how a spiral fits, but will follow this interesting thread.

Fossil Evidence seems to indicate that this world once had a daily universally warm climate.

Certainly there is Progression of the poles. For example Polaris is now the North Pole Star. But around 4000 years ago the North Pole Star was the star "Alpha Drakonos," the Eye of the Dragon -- Hence Santa, anagram of Satan, keeps his eye on people from the North Pole.

Anciently Drakonos was beloved to watch and keep his eye on people.

The Pyramid of Cheops in Egypt was aligned with Alpha Drakonos.

So their is a definite progression.

Another post claimed research on Quasars show they are speeding up in going away from us. So how does this first with perpetual motion.

Oh, and I have one copy of Nw Scientist that mentions a cluster of Galaxies that all show different rd shifts, though this cluster is thought to be all at the same distance from us. So that there are a quite a number of problems.

I am not an Astrophysicist, so do not claim to have the answers. But do find such problems intresting.
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  #31  
Old 25-10-2019, 06:23 PM
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Quote:
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This theory puts a restriction on all astronomers and geologists to within a very narrow range to explain the mysteries of great changes of climate in the past. These past changes in climate call for an explanation covering a greater range of obliquity.
Alan D.
No they don't, unless you have some remarkable new evidence you'd like to share that's in contradiction to the body of scientific understanding of geology and Earth's palaeoclimate. Merely saying "it was once warm at the Poles" is neither news, nor paradigm-shifting. Plate tectonics, stellar physics and (crucially) greenhouse gas changes cover the key observed variations very well.
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  #32  
Old 25-10-2019, 07:21 PM
morls (Stephen)
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Alan,
I get the impression you don't believe the science behind theories of anthropogenic climate change? Sounds like you are claiming the accepted science is flawed or somehow incomplete? (Well, all science is incomplete to an extent I suppose as theories are tested and new knowledge emerges...)
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  #33  
Old 25-10-2019, 10:14 PM
Multiverse (Grant)
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Quote:
Originally Posted by JohnF View Post
Well I had read many years ago that the earth travels in an Elipse shape. Not sure how a spiral fits, but will follow this interesting thread.

Fossil Evidence seems to indicate that this world once had a daily universally warm climate.

Certainly there is Progression of the poles. For example Polaris is now the North Pole Star. But around 4000 years ago the North Pole Star was the star "Alpha Drakonos," the Eye of the Dragon -- Hence Santa, anagram of Satan, keeps his eye on people from the North Pole.

Anciently Drakonos was beloved to watch and keep his eye on people.

The Pyramid of Cheops in Egypt was aligned with Alpha Drakonos.

So their is a definite progression.

Another post claimed research on Quasars show they are speeding up in going away from us. So how does this first with perpetual motion.

Oh, and I have one copy of Nw Scientist that mentions a cluster of Galaxies that all show different rd shifts, though this cluster is thought to be all at the same distance from us. So that there are a quite a number of problems.

I am not an Astrophysicist, so do not claim to have the answers. But do find such problems intresting.
'New Scientist' mags! They need to be thrown in the bin.
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  #34  
Old 26-10-2019, 09:38 AM
Dove (Alan)
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Alan,
I get the impression you don't believe the science behind theories of anthropogenic climate change? Sounds like you are claiming the accepted science is flawed or somehow incomplete? (Well, all science is incomplete to an extent I suppose as theories are tested and new knowledge emerges...)
Thankyou Moris

You are quite right, a serious flaw, stay tuned.

Cheers Alan D
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  #35  
Old 26-10-2019, 10:48 AM
morls (Stephen)
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Oh dear...

You talk of changes to the obliquity over the last 2000 years, well, I'll attach a figure charting temperature trends for the past 65 million years (Ma).

This figure is from a paper published on the "Proceedings of the National Academy of Sciences of the United States of America" website

It's probably not going to change your mind, but here is a link to the document:
https://www.pnas.org/content/115/52/13288


Here's an excerpt from the abstract to the article:

Here, we quantitatively assess the similarity of future projected climate states to these six geohistorical benchmarks using simulations from the Hadley Centre Coupled Model Version 3 (HadCM3), the Goddard Institute for Space Studies Model E2-R (GISS), and the Community Climate System Model, Versions 3 and 4 (CCSM) Earth system models. Under the Representative Concentration Pathway 8.5 (RCP8.5) emission scenario, by 2030 CE, future climates most closely resemble Mid-Pliocene climates, and by 2150 CE, they most closely resemble Eocene climates. Under RCP4.5, climate stabilizes at Pliocene-like conditions by 2040 CE. Pliocene-like and Eocene-like climates emerge first in continental interiors and then expand outward. Geologically novel climates are uncommon in RCP4.5 (<1%) but reach 8.7% of the globe under RCP8.5, characterized by high temperatures and precipitation. Hence, RCP4.5 is roughly equivalent to stabilizing at Pliocene-like climates, while unmitigated emission trajectories, such as RCP8.5, are similar to reversing millions of years of long-term cooling on the scale of a few human generations. Both the emergence of geologically novel climates and the rapid reversion to Eocene-like climates may be outside the range of evolutionary adaptive capacity.
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  #36  
Old 26-10-2019, 11:45 AM
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You are quite right, a serious flaw, stay tuned.
Cheers Alan D

This climate scientist is not going to hold his breath that Alan Dove, random commenter on the Internet, has succeeded where actual generations of climate deniers (sometimes funded by some of the world's biggest companies who knew the reality) have failed... to overturn 150 years of extremely well-established physics!! I've lost track of the number of 'eccentrics' who've come up with a novel unsupported weird theory (like 'spiral planetary motion', or 'iron Sun', various flavours of planetary gravitational influences, cosmic rays, multidimensional curve-fitting and the like). All consistently "ABC" (Anything But CO2). Not expecting the latest one will get even remotely close to explaining the full body of scientific understanding of planetary physics, geology, climate, oceanographic, atmosphere, biosphere, atmospheric chemistry, energy balance and all the rest...

Oh, and by the sounds of it, wants to toss out orbital mechanics too!
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  #37  
Old 26-10-2019, 05:00 PM
Multiverse (Grant)
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Not everyone understands 'The Scientific Method', one of the greatest ideas humans have developed (upon which all our modern civilization rests on). This despite being afforded every opportunity of a school 'first world education' and the continuing internet resources available for evidence-based findings.
I too despair at the sometimes wasted effort of the real school teachers and am irritated at the faith-based nonsense schools (which enable young minds to lose focus on reality).
Trying to argue with and becoming frustrated with the deluded is akin to wrestling with a pig in mud - there comes a point when you finally realise that the pig is enjoying it!
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  #38  
Old 26-10-2019, 07:28 PM
morls (Stephen)
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I agree that not everyone understands the intricacies of the scientific method, but why don't people trust scientists? When the United Nations backs the science, when the vast bulk of peer reviewed, rigorous research papers build the case that this is indeed happening, why do people instead say "no, they are wrong"? It's like me telling a brain specialist that his diagnosis of a neurological condition is wrong, because phrenology hasn't been taken into account.
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  #39  
Old 26-10-2019, 08:23 PM
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As a general comment on such discussions, I feel in any scientific argument it's important to argue the facts based on the evidence rather than any of the qualifications or lack of qualification of either proponent. Anything else tends towards activism however well intentioned it may or may not be.

If one is interested in hearing all views, contrary or otherwise, then people need to feel comfortable in expressing their views without ridicule or personal judgements. Otherwise all we have is open house for political correctness and non-contrarian views. We make the society we deserve.

Best
JA
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  #40  
Old 26-10-2019, 08:37 PM
morls (Stephen)
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I was commenting on the fact that on occasion people ignore or reject evidence-based arguments on the basis of ideological difference, even when they don't fully understand the field of endeavour with which they are engaging (or not engaging).
I don't think political correctness comes into it.
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