1. Do Now 1. ______deep v shaped cut in the c. shelf and c. slope 2.______flattest part of the ocean floor 3. _____flat topped seamount 4. _____pointy extinct volcano 5. _____longest underwater mountain range

2. 1.What is the atmosphere? 2. What is the composition of the atmosphere? 3. Why is Earth’s atmosphere important? 4.Why does Earth’s atmosphere exist? 5.How does oxygen get into the atmosphere?

3. 1. Atmosphere is a very thin layer of gases that surrounds the planet. Atmosphere comes from 2 Greek words 1. atmos-means vapor 2. sphaira-means ball or globe atmos sphaira

4. 2. Earth’s Atmosphere is made of nitrogen-78% most abundant gas oxygen-21 % 2 nd most abundant gas Trace gases-1% of gases (carbon dioxide gas traps heat) water vapor-gaseous form of water solids-salt, dust, smoke 2. What is the composition of the atmosphere?

5. Atmosphere on Earth make conditions suitable for living things by giving us 1.oxygen and other gases 2. traps sun’s energy and keeps earth warm enough for water to exist as a liquid 3. protects us from dangerous radiation from the sun 4. prevents us from being hit by meteoroids. 3. Why is Earth’s atmosphere important?

6. 4. Earth’s atmosphere exists because Earth has the right mass and distance from the sun 1. Why does Earth’s atmosphere exist?

7. 5. How does oxygen get into the atmosphere? 5. Oxygen gets into the atmosphere by plants taking in carbon dioxide and changing it into oxygen through photosynthesis.

8. This false-colored image was acquired during the Clementine mission. It shows airglow of the upper atmosphere as a thin blue line. The bright spot toward the right of the image is an urban area.