1. Guided Notes about the Earth’s Oceans Chapter 15, Section 1

2. 1. The Challenger was the first research ship exclusively devoted to oceanography, the scientific study of the oceans. The Challenger expedition investigated ocean currents, water temperature and chemical composition, seafloor sediments and topography, and marine life.

3. 2. The Meteor used sonar technology to map the seafloor features of the South Atlantic Ocean in the 1920’s.

4. 3. The Topex/Poseidon satellite monitors the ocean’s surface temperatures, currents, and wave conditions.

5. 4. Scientists hypothesize that Earth’s water came from two sources. When comets collide with the Earth, the impact releases water. During volcanic eruptions, water vapor and carbon dioxide gases are emitted.

6. 5. 97% of the water found on Earth is contained in the oceans. The remaining 3% is freshwater located in frozen ice caps, rivers, lakes, and groundwater.

7. 6. The global sea level has risen and fallen through the years in response to melting ice during warm periods and expanding glaciers during ice ages.

8. 7. All of the oceans are really one vast, interconnected body of water.

9. 8. The Arctic and Antarctic Oceans are covered by vast expanses of sea ice, particularly during the winter.

10. Describe pancake ice and how it can form pack ice: Since ice is less dense than liquid water, it floats. Thickening ice eventually solidifies into round pieces called pancake ice. These pieces can thicken and freeze into a continuous ice cover called pack ice. Since ice is less dense than liquid water, it floats. Thickening ice eventually solidifies into round pieces called pancake ice. These pieces can thicken and freeze into a continuous ice cover called pack ice.