As I understand it, the Pleistocene ice ages were dictated by three major factors suggested by the Serbian geophysicist Milutin Milankovitch--eccentricity (orbital shape), obliquity (axial tilt) and precession (direction of rotation in relation to fixed stars).

The one identical factor between our Earth and this alternate Earth is the eccentricity--no lower than 0.000055 and no higher than 0.0679 over a period of 100,000 years.

Back home, Earth's axial tilt varies between 22.1 and 24.5 degrees in a period of 41,000 years. In this alternate Earth, the tilt varies between 20 and 25 degrees in a period of 61,500 years.

Back home, Polaris will be the North Star for a total length of roughly 26,000 years. In this alternate Earth, Alioth in the Big Dipper will be the North Star for a total length of 46,800 years.

With these changes, how would Earth's climate been different? How would these changes affect the extents of the ice ages?

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    $\begingroup$ I think this question belongs in worldbuilding.stackexchange.com $\endgroup$
    – arkaia
    Dec 16, 2015 at 3:25
  • $\begingroup$ It's been dismissed as broad. $\endgroup$ Dec 16, 2015 at 3:52
  • $\begingroup$ Maybe instead of changing sites, you could try to rephrase the question in a more specific way. Good luck $\endgroup$
    – arkaia
    Dec 16, 2015 at 14:50
  • $\begingroup$ Rephrase it how? $\endgroup$ Dec 16, 2015 at 15:23
  • $\begingroup$ Ask about the specific effects you are looking for. There are many aspects to planetary climate and being specific in the effects you are considering, shows you have done some of the leg work. $\endgroup$
    – arkaia
    Dec 16, 2015 at 15:27