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Author Topic: Toward Improved Discussions of Methane & Climate  (Read 19934 times)

salbers

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Re: Toward Improved Discussions of Methane & Climate
« Reply #50 on: May 06, 2017, 10:53:35 PM »
The issue is not whether landmasses move from the rotational adis, they don't (except by tectonic movements which is totally different).  the rotational axis itself shifts, tilting or wobbling its position relative to the sun.  this is a historical cycle that normally does affect the cycle of glacial and interglacial periods.  however, climate change is progressing far more rapidly than any recent period, so i don't think any major earth changes that happen over a thousand years from now are particularly relevant today.  i DO think it's important to understand this in the context of paleoclimate data.
Indeed the Milankovitch cycles are important in the paleoclimate context. More specifically there are changes in the Earth axis tilt. Precession will also change which hemisphere is closest to the sun during a particular season. For example presently Antarctica has its summer when the Earth is near perihelion, so there is more reflection by the ice sheet. The lowers the Earth's overall temperature. A third cycle is changes in the eccentricity, so this would modulate the precession effect.