Multiple Choice
Climate reconstructions using oxygen isotopes (18O) over two timescales
Over the span of 70 million years,the Earth's climate
A) was much warmer 70 m.y.a.compared to the present.
B) was warmest approximately 10 million years ago and coolest about 56 million years ago.
C) has remained fairly constant,only showing a warming trend during the past 200 years.
D) was much cooler 70 m.y.a.compared to the present.
E) did not fluctuate greatly from approximately 500 m.y.a.to 65 m.y.a. ,then widely fluctuated until the current stable period.
Correct Answer:
Verified
Correct Answer:
Verified
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