1. The Role of Climate 4.1

2. Weather Condition of Earth’s atmosphere at a particular time and place.

3. Climate Average, year-after-year conditions of temperature and precipitation in a particular region.

4. Greenhouse effect Natural situation in which heat is retained in Earth’s atmosphere by carbon dioxide, methane, water vapor, and other gases.

5. Polar Zone Cold climate zone where the sun’s rays strike Earth at a very low angle.

6. Temperature Zone Moderate climate zone between the polar zones and the tropics.

7. Tropical Zone Warm climate zone that receives direct or nearly direct sunlight year round.

8. Key Concept How does the greenhouse effect maintain the biosphere’s temperature range? Natural situation in which heat is retained in Earth’s atmosphere by carbon dioxide, methane, water vapor, and other gases.

9. Key Concept What are Earth’s three main climate zones? Polar, temperate, and tropical are the three main climate zones of Earth.