The tilt of Earth's axis varies between and over 41,000 years (Milankovitch cycles). How does this variation affect Earth?
Show answer & explanation
Correct answer: A
Explanation
Correct Answer:
Greater tilt increases seasonal contrast
Explanation:
The tilt of Earth's axis (obliquity) varies between 22.1 and 24.5 degrees over a cycle of 41,000 years as part of the Milankovitch cycles. A 'greater tilt increases seasonal contrast', meaning summers become warmer and winters become colder, whereas a smaller tilt reduces seasonal contrast, resulting in cooler summers and milder winters.
Key Points:
Obliquity is one of the three Milankovitch cycles, alongside eccentricity and precession, which collectively influence Earth's long-term climate patterns and ice ages.
The current axial tilt of the Earth is approximately 23.44 degrees and is currently decreasing very slowly.
Important Questions and Answers:
Question: What is the approximate duration of one complete cycle of Earth's axial tilt variation (obliquity)?
Answer: Approximately 41,000 years.
Question: Who proposed the astronomical theory of ice ages based on Earth's orbital variations?
Answer: Milutin Milanković.