The ocean is Earth's interconnected body of salt water and a defining part of the planet. This lesson introduces its scale, major divisions, and relationship to land and the seafloor.
The ocean covers approximately 70.8% of Earth's surface and contains about 97% of Earth's water. Although people commonly speak of several oceans, they are connected parts of one global body of salt water. Oceanographers may call this the World Ocean or global ocean. The idea of connection matters because water, heat, gases, and living things can move between its regions.
All flashcards
What is the World Ocean?
It is the continuous, interconnected body of salt water covering most of Earth, including the Pacific, Atlantic, Indian, Southern, and Arctic oceans.
What is a sea?
A sea is generally a smaller division of the ocean that is partly or fully enclosed by land.
What is a continental shelf?
It is the relatively shallow submerged edge of a continent, made of continental crust and covered by ocean water.
What is an ocean basin?
An ocean basin is a large depression in Earth's crust that holds ocean water.
How does subduction shape the seafloor?
At a subduction zone, one tectonic plate moves beneath another. This can form deep trenches and is associated with earthquakes and volcanic activity.
Quiz questions
What defines the photic zone of the ocean?Answer: Water with enough sunlight for photosynthesis.
When do spring tides occur?Answer: When the Sun and Moon are aligned at new or full moon.
Which statement best defines an ocean current?Answer: A continuous, directed flow of seawater.
How does absorbed atmospheric carbon dioxide contribute to ocean acidification?Answer: It increases hydrogen ions, which lowers seawater pH.
What is a central purpose of marine protected areas?Answer: To conserve marine habitats and ecosystems through management.
Based on the Wikipedia article Ocean, licensed CC BY-SA 4.0. Adapted into a summary, flashcards and quizzes.