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Concerned
2013-Dec-16, 05:18 PM
Recent findings, http://www.newscientist.com/article/dn24755-earths-poles-are-shifting-because-of-climate-change.html#.Uq8v8-ddUal. Earths geographic north pole has shifted slightly, about 1.2m in 8 years, which, is slightly faster than the standard rate due to the natural wobble of the earth as it orbits the sun.

Concerned
2013-Dec-16, 05:23 PM
I think I have opened this in the wrong section, should probably be geology issue.

Swift
2013-Dec-16, 06:07 PM
I think I have opened this in the wrong section, should probably be geology issue.
We have the technology.... (moved from Q&A)

Concerned
2013-Dec-16, 06:42 PM
If you read the older article referenced within the text http://www.newscientist.com/article/dn17657-global-warming-could-change-earths-tilt.html, it was suggested in 2009 that changes in sea levels might cause a drift amounting to 1.5cm per year. However, from the latest article, above, the change appears to have been 1.2m in 8 years, so more than 10cm (4 inches) per year.

Concerned
2013-Dec-16, 06:53 PM
Reading the article again, the 10cm per year does not seem to be overtly unusual. It would appear that since 1899 a shift southwards at a rate of 10cm per year has been registered, but, this changed, with the direction of the shift turning eastwards.

dgavin
2013-Dec-16, 09:10 PM
I think if you were to dig through the Data, would would also find a shift of the pole (and the eintire curst) after each of the Sumatra, Japan, and Chilie Megatrust quakes over the past dozen years. The article contends that models show the direction suddenly changed in 2005 and it is related to climate change.

Unfortunatlly it has to contend with the 8.6. EQ in Sumatra in 2005, which followed the 9.3 Megathrust quake form the same region in 2004.

Climate change isn't sudden, and I would expect a sudden change in Polar motion to correlate with a sudden event of some kind. My Best feeling is thier Model accounted for this large mega quake and it's less large, followup event, but attributes them to the climate change.

I'd say the shift in direction though was more liekly triggered by the 9.3 megathrust, and its 8.6 near megathrust followup.

Concerned
2013-Dec-16, 10:27 PM
I think if you were to dig through the Data, would would also find a shift of the pole (and the eintire curst) after each of the Sumatra, Japan, and Chilie Megatrust quakes over the past dozen years. The article contends that models show the direction suddenly changed in 2005 and it is related to climate change.

Unfortunatlly it has to contend with the 8.6. EQ in Sumatra in 2005, which followed the 9.3 Megathrust quake form the same region in 2004.

Climate change isn't sudden, and I would expect a sudden change in Polar motion to correlate with a sudden event of some kind. My Best feeling is thier Model accounted for this large mega quake and it's less large, followup event, but attributes them to the climate change.

I'd say the shift in direction though was more liekly triggered by the 9.3 megathrust, and its 8.6 near megathrust followup.

Believe it or not, I had forgotten about the Boxing Day. Tsunamis.

dgavin
2013-Dec-17, 03:06 PM
Megathrust events and their effects are actually easy to over look in models that include them in a much larger dataset, like a that climate change model behind the article.

But when you remember that all three Megathrust events, and that one near megathrust event all reduced the diameter of the planet by 10's to 100's of meters each one, and the pole shift occurred near the same time as one of those events. Well...cause and effect and Occam's Razor and the like.

It's just a case where the model should of also filtered these events from it's datasets and the effects of them somehow. I'm not saying they were wrong, I'm just saying that it seems to need a lot more data work on other events like these, before you could say for sure it was climate change that caused the shift, and not the Megathrust events.

I'd put my money on the Megathrust events though. It's far too coincidental of a change to not be related in some capacity.

ngc3314
2013-Dec-19, 06:37 PM
Surely a diameter change of 10-100 meters is ruled out by data - long-baseline interferometry which solves for the relative antenna positions to centimeters, and GPS results if nothing else?

dgavin
2013-Dec-19, 07:57 PM
Surely a diameter change of 10-100 meters is ruled out by data - long-baseline interferometry which solves for the relative antenna positions to centimeters, and GPS results if nothing else?

It's an unknown, but from what I garneded out of that articale, it does not sound like they eliminated it, and it's possible effects from thier data.

Even if a long baseline would work out the singular Megathrust events, the direction change of the pole motion is also a singular event, orrucign around the time frame of two Megathust events. All I'm saying is you can't really ignore that, in favor of climate change, in this one case.

Saying that Two Megathrust events caused the pole shift, is as equally valid as saying Climate Change caused the same effect. There doesn't appear to be any work done as to deterime the real cause, or mentioning they eliminated the Megathrusts as a potential cause and the reasons for it's elimination.

It's not a bad model, but it just doesn't seem to account for other effects well. It doesn't seem completed yet.