Hydrosphere 8th Notes KSEEB Social Science
→ Atmosphere is a layer of gases dust Particles and water vapour surrounding the earth.
→ The earth is popularly Called Blue planet or watery Planet.
→ About 71% of the total area of the earth or 361 million Sq K.M is covered by water.
→ The major water bodies of the world are the Pacific ocean, the Atlantic ocean, the Indian ocean and the Artic Ocean.
→ Oceans are deep and large expanse of water found between the continents.
→ A sea is a part of the ocean extended or projected Inland.
→ Gulf is a pari of an ocean or sea that penetrates into the land.
→ Bays are small semi-circular water bodies partially surrounded by land.
→ Strait: A Strait is a narrow strip of water body joining two large water bodies Ex. Palk strait, Strait of Gibralter.
→ Isthmus is a narrow stretch of land mass joining two large land masses.
Ex. Suez Canal between the Mediterranean sea and the Red Sea.
→ The ocean floor is divided into 4 major parts They are
- The Continental Shelf
- The Continental Slope
- The Deep sea Plains
- The Ocean deeps.
→ The ocean water has 3 types of movements. They are waves, currents and tides.
→ Factors that influence ocean currents are rotation of the earth, temperature, wind, salinity, Shape of the Landmarks etc.
→ South Indian ocean currents are Mozambique, Madagascar etc.
→ Tides are the periodic rise and fall in the sea or ocean level. High tide, low tide arc two types of tides.