1 .		Which one of the following is NOT included in Earth's climate system?
2 .		Which one of the following is NOT a significant natural cause of climate change?
3 .		Which of the following help scientists discover how climate has changed over broad expanses of time?
4 .		Along with carbon dioxide, __________ is largely responsible for the greenhouse effect of the atmosphere.
5 .		When determining climate change, oxygen isotope measurements are made from an analysis of __________.
6 .		The primary effect on climate of a volcanic eruption depends on __________.
7 .		Which one of the following is NOT a greenhouse gas?
8 .		The person who first developed and strongly advocated the astronomical theory of climate change was __________.
9 .		Oxygen isotope analysis measures the __________.
10 .		Which of the following is a possible consequence of a greenhouse warming?
11 .		The slow wobbling of Earth as it spins on its axis is called __________.
12 .		Which one of the following is a significant contributor to increased levels of atmospheric carbon dioxide?
13 .		Which of the following is associated with the astronomical theory of climate change?
14 .		The combustion of coal and oil is a major source of which greenhouse gas?
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