This is a summary of some astronomical cycles that could influence the climate.  The daily and yearly cycles are obvious; and would be the strongest signals in any time series analysis, unless they are specifically excluded by choosing sampling intervals longer than a year.  Most of the other cycles are still matters of uncertainty and ongoing research.  The precession of the equinoxes, the variation of the inclination of the Earth's axis, and the variation of the orbital eccentricity are believed to be involved in the generation of ice ages, through the Milankovich mechanism.  However, despite the success of the Milankovich theory in explaining the recurrence of Ice Ages, there are some unresolved questions, such as why the 100,000 year variation of the eccentricy should seem to dominate the records of past climates.

(NAO and ENSO stand for "North Atlantic Oscillation" and "El Nino Southern Oscillation," respectively.  They involve coupled oscillations involving ocean currents and winds in the atmosphere.  Their phenomenology is well understood, but the causes remain uncertain.)

	Astronomical Cycles		Weather and Climate Cycles
			The daily weather variations are obvious
			The solar rotation period of 27 days is difficult to separate from the lunar month of 29.5 days
			The annual weather variations are also obvious
			NAO and ENSO result from variations in ocean currents at periods of 3 to 7 years
			The 11 year sunspot cycle affects the stratosphere; climate variations at 11 years are less certain The 18.6 year lunar tidal cycle may appear in some climate data but has not been proven
			A highly tuned 37 resonance in the lunar tidal cycle may appear in climate data in continental interiors. Major droughts on the Great Plains have occurred at intervals of 75 years
			A long period modulation of the sunspots is uncertain, but there have been several long periods with few sunspots
			The Little Ice Age suggests climate variations at 300 to 500 year periods
			Variations in the Earth's tilt and orbital inclination and eccentricity are involved in the Milankovich hypothesis of ice ages
			The galactic rotation may cause variations in space dust and the proximity to highly active stars

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The terminology of geological ages

The big events of Earth's history

Climate models

A technical note on the determination of periodic cycles from long trains of data

References and further reading