Ocean Systems 3.1 The oceans are a connected system. 3.2 CHAPTER NEW CHAPTER Ocean Systems the BIG idea The oceans are a connected system of water in motion. 3.1 The oceans are a connected system. 3.2 Ocean water moves in currents. 3.3 Waves move through oceans. 3.4 Waters rise and fall in tides. CHAPTER OUTLINE

3.1 The oceans are a connected system. • Much of Earth is covered by ocean water, which contains dissolved salts and gases. salinity density continental shelf sonar SECTION OUTLINE

3.1 The oceans are a connected system. • Much of Earth is covered by ocean water, which contains dissolved salts and gases. salinity • Ocean temperatures decrease with depth. density • The ocean floor has canyons, mountains, and many other features. continental shelf sonar SECTION OUTLINE

Ocean water moves in currents. 3.2 Ocean water moves in currents. • Surface currents are set in motion by winds and carry heat around the globe. ocean current upwelling downwelling El Niño • Deep currents are caused by differences in water density. Dense water sinks at the poles and very slowly flows toward the equator. SECTION OUTLINE

Waves move through oceans. 3.3 Waves move through oceans. • Ocean waves transport energy, not water. When a wave passes, water particles end up in the same places they began. longshore current rip current • Longshore currents occur when waves hit shores at angles. • Rip currents are narrow streams of water that breakthrough sandbars. SECTION OUTLINE

Waters rise and fall in tides. 3.4 Waters rise and fall in tides. The Moon’s gravity pulls Earth’s waters into bulges and dips. tide As Earth rotates, its movement through these bulges and dips causes tides. tidal range spring tide neap tide indirect high tide Earth Moon direct high tide SECTION OUTLINE

3.1 The oceans are a connected system. I. The oceans are a connected system. salinity A. Ocean water covers much of Earth. density B. Ocean water contains salts and gases. continental shelf 1. Salts sonar 2. Oxygen and Other Gases C. Ocean temperatures vary. D. The ocean floor has many features. 1. Ocean Exploration 2. Mapping the Ocean Floor KEY CONCEPT SUMMARY

Ocean water moves in currents. 3.2 Ocean water moves in currents. II. Ocean water moves in currents. ocean current A. The oceans have major currents. upwelling 1. Surface Currents downwelling 2. Deep Currents El Niño B. Currents interact with climate and weather. KEY CONCEPT SUMMARY

Waves move through oceans. 3.3 Waves move through oceans. III. Waves move through oceans. longshore current A. Waves form in the open ocean. rip current 1. Wave Action at the Water’s Surface 2. Wave Action near Shore B. Waves cause currents near shore. KEY CONCEPT SUMMARY

Waters rise and fall in tides. 3.4 Waters rise and fall in tides. IV. Waters rise and fall in tides. tide A. Coastal waters rise and fall each day. tidal range B. The gravity of the Moon and the Sun causes tides. spring tide 1. Daily Tides neap tide 2. Monthly Tides C. Tides can be used to generate electricity. KEY CONCEPT SUMMARY