Global Warming Shifts the Earth's Poles 482
ananyo writes "Global warming is changing the location of Earth's geographic poles, according to a study published this week. Researchers at the University of Texas, Austin, report that increased melting of the Greenland ice sheet — and to a lesser degree, ice loss in other parts of the globe — helped to shift the North Pole several centimeters east each year since 2005. From 1982 to 2005, the pole drifted southeast towards northern Labrador, Canada, at a rate of about 2 milliarcseconds — or roughly 6 centimetres — per year. But in 2005, the pole changed course and began galloping east towards Greenland at a rate of more than 7 milliarcseconds per year (abstract). The results suggest that tracking polar shifts can serve as a check on current estimates of ice loss. Scientists can locate the north and south poles to within 0.03 milliarcseconds by using Global Positioning System measurements to determine the angle of Earth's spin. When mass is lost in one part of a spinning sphere, its spin axis will tilt directly towards the position of the loss — exactly as the team observed for Greenland."
Three Gorges Dam (Score:5, Interesting)
Part of this shift could be caused by filling the reservoir behind the Three Gorges Dam, since that is on the opposite side of the world from Greenland. But that would only explain part of it, since the reservoir holds about 40km^3 and Greenland is losing about 240km^3 per year.
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With that said, why did they change from "centimeters" to "milliarc"?
What the hell is the ratio?
Re:Three Gorges Dam (Score:5, Informative)
With that said, why did they change from "centimeters" to "milliarc"? What the hell is the ratio?
A Nautical Mile [wikipedia.org] is one minute of arc. Since a NM is 1852 meters, an arc second would be 1852/60 = 30.87m, so a milliarcsecond would be 3.087. So the ratio is about 3.
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Re:Three Gorges Dam (Score:5, Informative)
. Meters and kilometers are strait-line measures, and can only approximate distance on Earth (unless you want to bore through the earth).
Which is bollocks. The one is not more "curved" than the other. Both can be used to measure distance on either flat ( Euclidean ) or curved surfaces.
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Ofc it is bollocks and you are wrong.
A nautical mile is the distance you get if you measure one arc minute at the equator of the earth. That happens to be something like 1852m.
This 1852m is called a nm. And this nm can be used to measure anything ou want.
You can define the speed of light with it, measure arbitrary distances etc. Regardless wether you do that in curved or flat environments.
Hint: it is not the arc minute that is relevant but the distance this arc minute gives you at the equator.
Re:Three Gorges Dam (Score:5, Interesting)
A nautical mile isn't an "imperial unit"
It's a nautical unit. It's actually Babylonian. It's useful for measuring the Earth because it's "close enough" to a minute of arc.
If Gunther had changed his surveyor's chain to 1/100 of a nautical mile in 1620, (instead of 1/80'th statute mile)^1 we wouldn't be talking about the Meter at all, as it would have been useless.
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BMO
1. A nautical mile is 92.06 chains. An adjustment of the chain to 100 per NM wouldn't have been a big difference, and made things even easier for surveyors and engineers.
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Every object has a natural stable spin axis, no matter how uniform it is or not. Actually, they have 2 stable axis to rotate on. Tape a book shut and toss it in the air spinning, it will be fine in a "flat" spin and will also be fine spinning about the center line of its longest dimension. try spinning it on the 3rd axis and it will tumble in an attempt to reach one of the 2 stable states (the one with lowe
Re:Three Gorges Dam (Score:5, Informative)
Something about this article just feels wrong. http://en.wikipedia.org/wiki/True_polar_wander [wikipedia.org] feels more right - just sits better in my gut. ;)
Re:Three Gorges Dam (Score:5, Funny)
I welcome our new Asian Overlords and their Moment of Inertia.
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Simple question (Score:3)
It's another check on the measurements. (Score:3, Informative)
Just like the age of something can be measured by multiple decay products, layer depth, and many other measures of archeological assessment, and when they are in agreement, you know your results are robust, this is another way to measure the loss of ice which, if it agrees with GRACE, land measurements and predictions from models, will indicate that the model results are robust.
It's even in the FS:
"The results suggest that tracking polar shifts can serve as a check on current estimates of ice loss."
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Not much, at least not yet, since polar drift is a common and permanently ongoing event - and full-on polar shifts happen every half a million years or so.
What it does do however is provide another data set to compare when measuring ice melt, and importantly one of which we have a much longer record.
Scientists like being able to test their results against other measurements. By using polar shift we can verify satelite data to confirm (or in some case disprove) what the measurements seem to say.
It's basicall
Re:Simple question (Score:4, Informative)
You're confusing the drift and inversion in the planet's magnetic pole with the drift in the planet's rotational pole. This article is about the latter.
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Spinny-Chair (Score:5, Interesting)
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How about Natalie Portman in a vat of hot grits spinning on an office chair? When she farts and creates a gaseous void near her well-formed posterior, what happens to the rotation rate of the chair?
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Actually, yes. If the Earth's mass is redistributed, its rotational axis and/or rate must move, depending on the redistribution. It's the difference between you spinning in the chair holding a lead brick, and spinning in the chair with the same mass evenly distributed about your person.
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To get any appreciable thrust at all, he'd at least need to use an M-80. Bonus points if the vectors of what's left of the body moving forward and the asschunks moving in the other direction are accounted for with high speed photography.
Sounds like a good MythBusters episode to me. They can jam ever increasing amounts of explosives up the ass of pig carcasses.
Re: Spinny-Chair (Score:4, Informative)
You seem to be talking about the magnetic poles, which are indeed caused by the spin of the core and move a lot every year, in the magnitude of 50 km/year. This is so much that navigating using a compass requires compensating for the specific declination of that year. You can even observe it if you have a good bearing compass: take the bearing from a fixed position to a relatively far away object, such as a broadcast tower. A couple years later, take the bearing again, and (depending on your location) it may have changed by one or even several degrees.
TFA talks about the geographic north, e.g. the intersection of the surface and the axes around which the earth spins. This does not generally move around much, as it is affected by the distribution of mass around the earth causing the axis to shift. According to TFS, it can be measured using GPS, and moves in the magnitude of centimeters per year.
Surface Drift Question (Score:2)
Just curious - since the continental drift we acknowledge is about a cm per year, and we're all floating anyway, could this also be seen as a drift of the whole surface? I.e.: Could it be that the poles are actually stationary and the surface as a whole (as opposed to continents drifting relative to each other) moves?
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Could it be that the poles are actually stationary and the surface as a whole (as opposed to continents drifting relative to each other) moves?
A shift in the surface would cause a shift in star positions, including but not limited to the sun's apparent orbit. In addition, we know from looking at iron ore of several instances where the Earth's magnetic poles have completely switched positions in the past.
Of course, general relativity means there is no center of the universe, and you could just as easily measure the surface in relation to the magnetic poles as the magnetic poles in relation to the surface. But that didn't seem to be what you were im
Re:Surface Drift Question (Score:5, Insightful)
The crust does drift, and because the crust does not have uniform thickness, crustal drift changes the center of gravity and angular momentum of the Earth, and also shifts the poles.
Also, if there is a major earthquake that sinks a large portion of crust any appreciable amount, the rate of rotation AND center of gravity change, and poles shift some more.
There are many many vectors of change for the position of the poles. To assume that all of the observed drift is due to the change in mass of a single ice sheet is ludicrous. But, we're talking about the chicken little global warming narrative here, so anything goes.
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The technique they used is neither complex, controversial, new, nor specific to climate science.
it all goes south from here... (Score:4, Funny)
Re:it all goes south from here... (Score:4, Funny)
Well, you're facing south, so east is to your left.
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Surely, south is to your left?
Re:it all goes south from here... (Score:5, Funny)
A quick bit of projection math tells me the value of east is the set of all angles when you're at the north pole.
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A should hasten to add that this is true only in as much as the limit is concerned. At the actual precise north pole, the value of east is 0/0.
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Counterclockwise.
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My close personal friend (Score:2, Funny)
I traded email with my close personal friend at the University of Texas, Austin, Dr. Dyslexic.
He is aware of these finding and believes it is clear evidence of the hand of Dog at work.
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That's funny. I live in Texas, and the University of Houston attendees I queried here say: "Let's test it to be sure!" They suggested that with enough world-wide cooperation we could move enough water with dams to modify the moment of inertia and thus control the movement of the pole -- One small step towards taking the helm of Spaceship Earth. I guess such ideas are to be expected after all those years as the home of NASA's mission control...
Well, one of them did offer that we should check the south
Shifting Poles (Score:5, Funny)
There was this guy called Adolph that shifted the Poles too
GPS reference system (Score:4, Interesting)
I wonder how this affects high-accuracy geodetic GPS measurements. The GPS coordinate system is defined by the Earth's axis.
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Re:GPS reference system (Score:4, Interesting)
What I imagine is going on here, is that there is a ring of base stations watching the GPS satellites around each pole. If you know the base stations haven't moved w.r.t. the pole, then you can calculate where the center of spin is, thus where the pole is.
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To use the GPS satellites to determine the poles, presumably there are other ways than actually standing on the pole and getting GPS signals.
Also, we lump it together and call it GPS, but in fact there are several systems, and as I recall GLONASS (the Soviet/Russian one) is a lot more accurate in polar areas.
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We did not lose mass. (Score:3)
WE'RE ALL GONNA DIE!!!! (Score:2, Funny)
This is going to cause earthquakes and locusts, people!!!!!! The end is nigh!!!!! Pray to Mother Earth for forgiveness!!!!!!
WTF? has been happening for years (Score:3, Informative)
i first read about this a decade ago and it has been happening for hundreds of years. scientists are studying ships' logs from the 1700's and earlier and this process started 300 years ago.
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Are you sure you're not thinking about stars shifting? I have a hard time thinking about a compass from 300 years ago being accurate enough to measure this. I guess if it had a LOT of datapoints, maybe?
Re:WTF? has been happening for years (Score:4, Interesting)
Re:WTF? has been happening for years (Score:4)
i first read about this a decade ago and it has been happening for hundreds of years. scientists are studying ships' logs from the 1700's and earlier and this process started 300 years ago.
Ships used compasses (likely GPS now), which use the magnetic north & south poles - we've known about them moving about the place for ages, and even flipping. This is about the geographic poles which are at different locations - the Earth spins around these..
Great news for the USA (Score:2)
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Wait... we're killing off all the global worms now?
When will the madness end?
I said this already.... (Score:2)
Funny, I mentioned the same thing, with the same end result and whether it is global warming, or my reasoning is that there were other types of gravitational pulls from within further in the galaxy that sort of gave us a 3rd axis, that would eventually change the other 2 pulls of the earth (spinning and orbiting). The galaxies has orbiting solar systems too, so technically these gravitational fields affect the planets (earth) as well, not just our sun....
In the end the result is the same, I explained in my
This is awesome (Score:2, Insightful)
Awesome in how much of an epic fail this "scientific" research.
Regardless of global warming, I don't need a geology degree to know the geographic poles shift constantly, and if you measured their location over millions of years, you could realize that there is so much involved in where they are located, like continental drift or earthquakes or ice ages, to realize this is a completely meaningless study.
But of course retarded greenists are just going to add this to their list of "proof" about how the planet
Global Warming my Arse... (Score:2, Insightful)
Okay, for the past five years or so I've experience some of the most frigid winters. We had an extremely cold winter. Followed by a winter with record snow (4 ft in two days). Followed by a year with a mild winter but a huge snow in fall and a late frost in April. Then this past winter we've had snow flurries on about 1/2 the days. And now, in the middle of may we had a frost wipe out my second planting of sweet potatoes and peppers.
This is well past the Farmer's Almanac.
So seriously, F-GW, F-AlGore, F-I
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We know the effect of the Fukishima earthquake on the Earth's polar rotation, both through models and measurements (which are in accordance with one another). Actually, the same models used by the authors of this study.
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Okay, for the past five years or so I've experience some of the most frigid winters. We had an extremely cold winter. Followed by a winter with record snow (4 ft in two days). Followed by a year with a mild winter but a huge snow in fall and a late frost in April. Then this past winter we've had snow flurries on about 1/2 the days. And now, in the middle of may we had a frost wipe out my second planting of sweet potatoes and peppers.
Weather is not climate.
Re:Global Warming my Arse... (Score:5, Insightful)
Congratulations, you just demonstrated how little you know about climate science and global climate change. Colder winters and longer winters are both explainable and predictable depending on where you are. For instance, changes in the currents in the ocean may direct colder water towards the UK and northern Europe, thereby actually making for colder winters and more snow. In North America this year, the melting Arctic icecap (which melted much more than usual last summer) added extra heat to the northern oceans, which affected the jetstream, pushing it south. That dragged cold air from the Arctic down much further south.
Climate is wild and woolly, and it's hard to know exactly what's going to happen, but we know enough of what's going to happen and what's happening that most of the complaints you're going to come up with can be explained by Science. And not just some random scientist, but peer-reviewed and published science.
http://www.rawstory.com/rs/2013/03/25/scientists-long-winter-in-u-s-the-result-of-melting-arctic-ice-cap/ [rawstory.com]
We know the poles shift. In fact, that's IN THE SUMMARY. You didn't even have to read the article to see that shifting geographic poles are well known. But they're shifting faster, and NASA's GRACE experiment is also helping measure the subtle shifts in gravity associated with shifting mass. It all seems to be correlating well. Someone else here has even already pointed out this comment in the article:
"The results suggest that tracking polar shifts can serve as a check on current estimates of ice loss."
Are you interested in science or not? Then sit and read and understand the science. Don't go off on a rant before you know a single damn thing of what you're talking about.
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Just fix it (Score:2)
I thought ... (Score:2)
Galloping? Really? (Score:3)
galloping east towards Greenland at a rate of more than 7 milliarcseconds per year
>galloping
>milliarcseconds/yr
To put it into english:
1 arcsecond is 1/3600 of a degree (1/(60x60)). One thousandth of this is 1/3,600,000 degree. There are 7 of these per year.
I will leave it to the reader to determine how many thousands of years it will take to move one degree from where it is now, excluding normal precession.
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BMO
polar shift is a branch of geophysics (Score:3)
A closely related geophhyscial measurement is Length-of-Day, that is the time between repeat viewing of stars which varies nanoseconds per day and milliseconds per year. All the same large earth mass-moveoments that shift poles also change Length of Day.
Global warming causes everything! (Score:3, Insightful)
Is there anything that isn't caused by global warming? It's getting silly at this point.
Not so drastic (Score:3)
I got thinking that many Aztec, Mayan, Egyptian and other nations have left us with structures (pyramids, temples, etc) strongly aligned with stars and other celestial items. Seems they are still aligned, despise 1000s of years. If the Earth has been shifting since eons, how come those are still aligned?
If you are tempted to say the time scale isn't the same, remember that in only 8 years, it's moved 20cm according to the fine summary and we're not experiencing the first GW.
The points of this post is not to discredit GW, nor the shift we observe, nor the Grand History of mankind as we know it, but to gather opinions on how to reconcile those 2 seemingly incompatible points.
JigJag
Re:The opposite might also be true (Score:5, Interesting)
I was actually going to post something incredibly close to this. The causal link just isn't there, as far as I can tell. It could very well be that the glaciers melt/freeze due to slight shifts in the poles' positions and variations in the Sun's output.
Re:The opposite might also be true (Score:5, Insightful)
I agree. Global warming may or may not be caused by humans. Perhaps in part. Regardless, we should focus on cutting pollution even if global warming is not man-made.
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And if it is, too goddamn bad, because I'm not giving up my Buick for some sissy electric car that doesn't even have exhaust pipes.
Plus, Jesus is gonna come back way before we have to worry about global warming. And when he gets back, he's not going to want to see a bunch of Priuses. He's going to want to see 400hp American Iron.
Re:The opposite might also be true (Score:4, Funny)
"Do unto others as you would have them do nought to sixty."
Actually by that metric the electric vehicles are still ahead.
Yeah, but in America we don't USE metric.
How will it make it worse? (Score:2, Funny)
What if it makes everyone live forever? What if it makes money grow on trees? What if it makes us travel back in time to the age of the dinosaurs?
How will it make it worse.
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Dramatically increased cost of living causing crippling economic distress on the poor.
... which causes them to have lower life expectancy, and higher infant mortality. So they have more kids to compensate, and the population goes up. Even if a Kenyan emits a tenth of the CO2 of an American, if they have three times the birthrate they will still "win" after two generations. In the long run, the best way to fight global warming is to control population, and the best way to do that is to fight poverty and provide better healthcare and education to poor, high-birthrate countries. I have read
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As in Fallen Angels [wikipedia.org], where anthropogenic global warming was the only thing preventing the onset of a new global Ice Age.
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It could very well be that the glaciers melt/freeze due to slight shifts in the poles' positions and variations in the Sun's output.
Yeah it could be. I suppose since we have no way of measuring the sun's luminous output with any precision at all we're all just guessing here.
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I'm afraid your sarcasm is going to go straight over the heads of slashdot's resident climate denialists.
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I'm afraid your sarcasm is going to go straight over the heads of slashdot's resident climate denialists.
I guess it's impossible to not run afoul of Poe's law because the level of genuine lunacy is so high.
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We're talking about climate not weather you moran.
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Stupid lack of sarcasm font. Of coursesolar output has an effect.
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It may have been reasonable to believe that if you had no information whatsoever about e.g temperature and rainfall or solar output.
The causal link is freshman physics (Score:3, Insightful)
If you take the known mass transfer between the ice sheets and the ocean, you can predict its effect upon the rotational axis of the Earth. You can then compare that prediction to what's actually observed by measurements of the location of the rotational axis of the Earth. This is what the paper did.
Re:All Just a SWAG (Score:4, Informative)
Not at all. It's a method that's proven itself repeatedly in studies on other subjects, such as the inner structure of the Earth and the measurement of earthquakes. If you'd rather believe that geophysicists studying the earth's mantle who've never written a climate science paper in their lives are also part of The Conspiracy you're welcome to, but you're rapidly going to find yourself as the only one who isn't In On It.
Re:The opposite might also be true (Score:5, Insightful)
There are plenty of things we can do. There's very little we *want* to do.
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Re:The opposite might also be true (Score:5, Insightful)
Re:The opposite might also be true (Score:5, Informative)
Re:The opposite might also be true (Score:5, Insightful)
Changes like this have happened time and time again ... and the world will continue and life will continue
The problem is it might not be habitable by 7billion humans ... this *will* affect you
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There is pretty clear causality here - melting ice results in a shift of mass on the surface of the Earth, which causes a change in the moments of inertia and products of inertia of the planet - due to conservation of angular momentum this results in the axis of rotation shifting.
Re:The opposite might also be true (Score:4, Insightful)
It's a bit of a stretch to suppose that there's some other force changing the Earth's angular momentum in just such a way as to be the same as that expected from the mass transfer from the Greenland ice sheet to the oceans.
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Or to paraphrase, "Brakes are gone...no point in steering!"
There's lots of stuff we can do to make sure that we're not making things worse. We know we're making SOME things worse, so why don't we stop it with those things?
Climate changes. But climate changes tend to happen on geological timescales, barring utter catastrophe. I'm sure the K-T Boundary impact changed the climate, but that was a world-changing catastrophic impact that effectively lit the atmosphere on fire for a few hours. I haven't seen one o
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Let's imagine that aliens start to pour carbon dioxide and other greenhouse gases into the Earth's atmosphere. The greenhouse effect has been known for over 100 years so we quickly can conclude that the net effect would be a warmer atmosphere. We would definitely try to do something to the matter, because well, the risk assessments would be increasingly worrying.
So why is it so difficult to act now?
And true, the climate has changed. Also it's normal that gamma ray explosions happen in space and they might d
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Yet another story from the warmist conspiracy, piling more so-called "science" on top of their propaganda.
The reason for the pole shift is simple. Due to a toxic spill of lead and cadmium paints, Santa Claus was forced to move his workshop slightly. The Elves are no longer permitted egg-nog while on duty.
P.S.
I'm a climate skeptic goddamnit. It really pisses me off when warmists keep calling me a denialist. Only people with no real evidence to back up their case resort to name-calling. Until someone can prov
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Scheduled maintenance.
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No, you'll get the real 'oops' when you will realise that you didn't check that 'Post Anonymously' box.... twice.
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Actually, they did.
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I know you're being ironic, but I'd like to point out he's also completely wrong.
The effect of continental drift, ice melting, ocean temps, etc is a quite long studied subject (see ref below which mentions George Darwin already looked at polar wobbling). I admit not everything about the wobbling is fully understood, but at least since 2002 [1] we are quite confident that the Greenland ice melting is significant enough to cause an effect on polar motion.
The fact that random people here often think they did a
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We've all been there. Don't sweat it.
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I won't go into your astronomical thoughts, beyond stating that yes, there are minor fluctuations in planetary dynamics due to gravitational interactions between them, but they are fairly small even on geological time scales, the sun and moon are the only bodys that have any significant effect on the Earth. due to their tidal forces, all other planets are so comparatively tiny and far away that they have minimal tidal effects and cause little more than slight variations in our orbit.
The renewal of the Earth
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Antarctic sea ice has grown some but sea ice is not what we're talking about here. It's the glacial/ice sheet ice that is solidly grounded on land that is causing this. I doubt whether sea ice in the Antarctic or Arctic has much effect on this.