Glacial ice cores provide a record of past temperatures based on
A) oxygen isotopes in the ice's water molecules.
B) the ancient temperature still preserved in the ice.
C) the thickness of ice layers.
D) the microfossils trapped in the ice.

Question

Quizplus · Accepted Answer

Glacial ice cores provide a record of past temperatures based on the ratio of oxygen isotopes (O18 and O16) found in the water molecules within the ice. The ratio of these isotopes is dependent on the temperature and climate conditions at the time the ice was formed, allowing scientists to infer past temperature changes.

Glacial Ice Cores Provide a Record of Past Temperatures Based