Ice Ages & Tilting Earth: Separating Fact from Fiction

[HankDorsett]

TL;DR

Recent study I've read

I came across an article regarding a study that claimed ice ages correspond with extreme changes in the tilt of the Earth. I'm curious what others think about this. Is this just another unqualified scientific study put out there to confuse the climate change debate? Is the science behind it accurate?

 

[Vanadium 50]

I came across an article

Are you going to tell us which one and where we can find it?

 

[HankDorsett]

Are you going to tell us which one and where we can find it?

https://www.livescience.com/6937-ice-ages-blamed-tilted-earth.html

 

[phyzguy]

This is not a new idea, try looking up "Milankovitch cycles". However, I don't quite see how you could read the article and call +/- 1 degree changes in the Earth's tilt "extreme changes".

 

[Genava]

Summary: Recent study I've read

I came across an article regarding a study that claimed ice ages correspond with extreme changes in the tilt of the Earth. I'm curious what others think about this. Is this just another unqualified scientific study put out there to confuse the climate change debate? Is the science behind it accurate?

Milankovitch cycles are viewed as the trigger of those changes. But the rate of changes in temperature cannot be explained by the changes in solar radiation and in the seasons. Neither the Milankovitch cycles are matching exactly the temperature interpreted from ice cores. In fact to explain the changes, feedback cycles are involved. Notably ice-albedo, CO2 and water vapor feedbacks. So the current understanding is that changes in incoming solar radiation and in seasons are triggering changes in greenhouse gases and in ice cover, century after century.

Some scientific publications about this:
1984, Modelling the global climate response to orbital forcing and atmospheric carbon dioxide changes: https://www.nature.com/articles/310757a0
1993, Water vapour, CO2 and insolation over the last glacial-interglacial cycles: https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.1993.0110
2006, Ice-driven CO2 feedback on ice volume: https://www.clim-past.net/2/43/2006/cp-2-43-2006.pdf
2011, The role of orbital forcing, carbon dioxide and regolith in 100 kyr glacial cycles: https://www.clim-past.net/7/1415/2011/cp-7-1415-2011.pdf

About the actual climate change, the Milankovitch (or orbital) parameters are changing in the direction of a cooling since the beginning of the Holocene (so for several millennia).
You can visualize here the changes: https://biocycle.atmos.colostate.edu/shiny/Milankovitch/

Edit: I add this review paper I just found.
2015, Quaternary glaciations: from observations to theories: http://www.science.earthjay.com/ins...ssion_03/QuatStrat_Discussion_Paper_Week4.pdf

 

[phyzguy]

@Genava , in addition to this nice list of papers, I would also add the following paper:

2013, Insolation-driven 100,000-year glacial cycles and hysteresis of ice-sheet volume:
https://www.nature.com/articles/nature12374
I think this paper does a very nice job of showing that, while the Milankovitch cycles are the main driver, other factors, like the rate of rebound of the continents after ice sheet melting, play significant roles as well.

 

[HankDorsett]

Thanks for all the responses, it's a lot to go over. All of this seems to prove my belief on climate change, climate science is way more complicated then led to believe.

 

[phyzguy]

Thanks for all the responses, it's a lot to go over. All of this seems to prove my belief on climate change, climate science is way more complicated then led to believe.

Of course it's complicated. What reputable climate scientist ever said otherwise?

 

[HankDorsett]

Of course it's complicated. What reputable climate scientist ever said otherwise?

I wasn't referring to any reputable climate scientists. Most of what we hear about climate change is from non educated sources and unfortunately they only talk about one issue.

 

[Genava]

I wasn't referring to any reputable climate scientists. Most of what we hear about climate change is from non educated sources and unfortunately they only talk about one issue.

If you are looking for reliable sources with articles and explanations wrote by researchers, there are CarbonBrief and ClimateFeedback.

 

[fastfreecurrent]

Could the Earth's wobble be a result of a massive meter impact and can that impact point be located by the wobble we have today-?

My guess is the Gulf of Mexico was created by this impact.

What’s your guess?

 

[phyzguy]

Could the Earth's wobble be a result of a massive meter impact and can that impact point be located by the wobble we have today-?

My guess is the Gulf of Mexico was created by this impact.

What’s your guess?

What "wobble"? Do you mean the tilt of the Earth's axis relative to the plane of the Earth's orbit? Or do you mean the long-term small changes in inclination ad ellipticity. Thease latter are well explained by the gravitational pull of the sun and moon

 

[fastfreecurrent]

What "wobble"? Do you mean the tilt of the Earth's axis relative to the plane of the Earth's orbit? Or do you mean the long-term small changes in inclination ad ellipticity. Thease latter are well explained by the gravitational pull of the sun and moon

The Chandler wobble or variation of latitude is a small deviation in the Earth's axis of rotation relative to the solid earth,[1] which was discovered by American astronomer Seth Carlo Chandler in 1891. It amounts to change of about 9 metres (30 ft) in the point at which the axis intersects the Earth's surface and has a period of 433 days.[2][3] This wobble, which is a nutation, combines with another wobble with a period of one year, so that the total polar motion varies with a period of about 7 years.

https://en.wikipedia.org/wiki/Chandler_wobble

 

[mfb]

Could the Earth's wobble be a result of a massive meter impact and can that impact point be located by the wobble we have today-?

No. A meteor impact can change the rotation rate and axis, but it doesn't lead to any long-term wobbling. There were also no impacts large enough to be relevant for Earth's rotation after the early phase where Earth formed.