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THE GLOBAL WARMING TEST

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Question 8:

Which answer below provides the best explanation for the following temperature record?

Industrial pollution from factories, power plants, and cars caused global warming
Natural variations in global temperatures may occur in roughly 500-years cycles
Global cooling occurred as a result of the Renaissance Period

The primary cause of variations in global temperature is due to the cycles of the sun and Earth's orbit about the sun. In addition to 40-year cycles and 500-year cycles, other temperature cycles include:

• 21,000 year cycle: Elliptical orbit of the Earth around the Sun (precession of the equinoxes)
• 41,000 year cycle: Cycle of the +/- 1.5 degree wobble in Earth's orbit
• 100,000 year cycle: Variations in the shape of Earth's elliptical orbit ( cycle of eccentricity )

Question 9