Why Is It That Oxygen Isotopes in Glacial Ice Can

question 81

Multiple Choice

Why is it that oxygen isotopes in glacial ice can be used to estimate mean ocean surface temperatures in the past?

• A) Large glaciers and ice sheets tend to be near the oceans.
• B) The ratio of ¹⁸ O to ¹⁶ O in vapor from warm water tends to be higher.
• C) Most of the atmospheric water vapor that falls as snow had evaporated from seawater.
• D) Water that contains ¹⁶ O is lighter.

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Definitions:

Modern Portfolio Theory

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Markowitz

Harry Markowitz, an economist who developed Modern Portfolio Theory, emphasizing the benefits of diversification.

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