A high concentration of oxygen 16 found in the ice caves of Antarctica and Greenland would indicate ____ at the time the ice was formed.
A) cold air temperatures
B) mild winters
C) intense ultraviolet radiation
D) the caves were under the ocean

Question

Quizplus · Accepted Answer

A high concentration of oxygen 16 in ice indicates a colder climate at the time of ice formation because oxygen 18 is more likely to precipitate out as snow during cold periods, leaving more oxygen 16 behind in the ice. Therefore, a high concentration of oxygen 16 found in the ice caves of Antarctica and Greenland suggests colder air temperatures when the ice was formed.

A High Concentration of Oxygen 16 Found in the Ice