Question

Which is true about climate change?

	A.	Greenhouse gas emission (e.g., CO2) from human activity is the major cause of recent climate change, including global warming.
	B.	Examination of CO2 trapped in ice cores demonstrates the global warming we are seeing now is part of a natural cycle that has been occurring over the last 800,000 years.
	C.	Examination of CO2 trapped in ice cores demonstrates the global warming we are seeing now is dramatically faster than anything in the last 800,000 years. It is thus unprecedented and not part of a natural cycle.
	D.	Variability in solar output (sun's temperature) and the orbit of the earth are significant causes of recent climate change, including global warming.

Answer 1

ans: B. Examination of CO₂ trapped in ice cores demonstrates the global warming we are seeing now is part of a natural cycle that has been occurring over the last 800,000 years.