Oceans and Life
Chapter 10 of the Class 9 Social Science NCERT textbook (Understanding Society: India and Beyond (Part 2)), "Oceans and Life", explores the ocean floor's landforms, the movements of ocean water, marine resources, maritime zones, and the early warning systems that protect coastal communities. Students gain a clear understanding of how oceans shape climate, support livelihoods, and are governed by international law — essential knowledge for the CBSE board exam.
- 1The Mariana Trench (Pacific Ocean) is the deepest place on Earth; the Mid-Ocean Ridge is the world's longest underwater mountain range.
- 2Spring tides occur when the Sun, Earth, and Moon align (full moon / new moon); neap tides occur during first- and third-quarter moon phases.
- 3India's coastline is 11,098.81 km long; major tidal energy sites include the Gulf of Kutch, Gulf of Khambhat, and the Sundarbans.
- 4The Exclusive Economic Zone (EEZ) extends up to 200 nautical miles from a country's baseline under UNCLOS.
- 5The 2004 Indian Ocean Tsunami claimed around 2,30,000 lives; it led countries to establish tsunami early warning systems.


