Chapter 2: Oceans and Continents
Most of our planet is covered by water. In this chapter we explore how land and water are spread across the Earth, meet the five oceans and seven continents, and find out how oceans shape life on Earth.
In this chapter you will
- compare how much of Earth is land and water
- name the five oceans and explain waves, tides, currents and ocean disasters
- name the seven continents and some islands
- explain why oceans matter and how to protect them
Topics
- The Distribution of Water and Land NCERT 2.1
About 71% of Earth's surface is water and 29% is land; most water is salty.
- Oceans NCERT 2.2
Five connected oceans: Pacific, Atlantic, Indian, Southern, Arctic; the Pacific is the largest.
- Continents NCERT 2.3
Seven continents: Asia, Africa, North America, South America, Antarctica, Europe, Australia.
- Oceans and Life NCERT 2.4
Oceans are full of life and give us food, oxygen, trade routes and a gentle climate.
Key words
- Continent
- a very large land mass
- Ocean
- a huge body of salt water
- Island
- land surrounded by water on all sides
- Tide
- the daily rise and fall of the sea
- Current
- a stream of moving water inside the ocean
- Tsunami
- a huge wave caused by an undersea earthquake
Summary
- About 71% of Earth's surface is water, mostly salty; the Northern Hemisphere has more land.
- Five connected oceans; waves, tides and currents move their water; tsunamis and cyclones are ocean disasters.
- Seven continents that slowly drift, and many islands.
- Oceans support life and trade; pollution and overfishing harm them.