Increasing ratios of oxygen-18 to oxygen-16 in glacial ice indicate ________.
A) advancing ice sheets
B) warming temperatures
C) increased volcanic emissions
D) uplift of land surfaces

Question

Quizplus · Accepted Answer

Increasing ratios of oxygen-18 to oxygen-16 in glacial ice are indicative of warming temperatures. This is because heavier isotopes of oxygen (O-18) evaporate less readily and condense more readily than lighter isotopes (O-16), leading to a higher ratio of O-18 to O-16 in precipitation during warmer periods.

Increasing Ratios of Oxygen-18 to Oxygen-16 in Glacial Ice Indicate