unit 11 lesson 1 what are the oceans like? · 11.02.2018 · •the floors of all the world’s...

Unit 11 Lesson 1 What Are the Oceans Like?

Copyright © Houghton Mifflin Harcourt Publishing Company


That’s a Lot of Water!


11.1 videos/Children's_ Continents and Oceans.mp4




• Five oceans separate and surround Earth’s landmasses.

• They are, from largest to smallest, the Pacific, Atlantic, Indian, Southern, and Arctic Oceans.




• Oceans cover about 71% of Earth’s surface, almost three times the area that land covers.




• Effects of oceans on life on land.


Same Ocean, Different Water


11.1 videos/The Deep Sea - Exploring the Zones.mp4




Problems Faced by divers:

1. Ocean water is salty, so you can’t drink it. The saltiness of water is its salinity.

• Salinity makes water denser, so boats float more easily in the ocean than they do in fresh water.

2. Exploring beneath the ocean’s surface requires SCUBA tanks for air and suits to keep warm.

3. Water pressure is the force of water pressing against whatever it surrounds.

11.1 images/SALINITY D.png

11.1 images/WATER PRESSURE D.png




• At certain depths, a submersible—an underwater vehicle which provides air, light, and protection from water pressure and cold—must be used.

• Some places are too deep for human-driven submersibles, so robotic submersibles are used.


Is the Ocean Floor Flat?


• The floors of all the world’s oceans share roughly the same features.

11.1 videos/The Ocean Floor Revealed.mp4




11.1 images/CONTINENTAL SHELF D.png

11.1 images/CONTINENTAL SLOPE D.png




11.1 images/ABYSSAL PLAIN D.png

11.1 videos/Formation of The Mariana Trench.mp4

https://www.purposegames.com/game/ocean-floor-features-game


Islands Come and Go


1. Oceanic trenches form where two plates meet and one sinks beneath the other, releasing magma at the boundary.

11.1 videos/Mariana Trench Formation.mp4


Islands Come and Go


2. Volcanic island chains form at plate boundaries and grow until they poke into the air, creating volcanic islands.

• The islands weather and erode over time and eventually disappear beneath the water again.


Islands Come and Go


3. In tropical regions, coral reefs form in shallow water around volcanic islands. These reefs can grow until they encircle an island.

• A reef can come out of the water, forming land that surrounds a lagoon of shallow water.

4. When a volcanic island sinks far enough to disappear, the ring-shaped coral, called an atoll, is left around the lagoon.

11.1 videos/Four Kinds of Coral Reef.mp4


Islands Come and Go


unit 11 lesson 1 what are the oceans like? · 11.02.2018 · •the floors of all the world’s...

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