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| q |
Over time, the tilt angle varies in a narrow
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range (22.2° ~ 24.5°).
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| q |
These variations are caused by the
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gravitational tug of large planets, such as
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Jupiter.
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| q |
The present-day value of the tile is decreasing.
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| q |
Cyclic changes in the tilt angle occur at a
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period of 41,000 years.
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| q |
Changes in tilt cause long-term variations in
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seasonal solar insolation received on Earth.
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| q |
The main effect of tilt changes is to amplify or
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suppress the seasons: increase tilt amplifies
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seasonal differences, decreased tilt reduces
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them.
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