These Movements of Ocean Water Class 11 Geography Notes explain the different types of ocean water movements including waves, tides and ocean currents. The chapter discusses causes, characteristics, types and importance of waves, tides and currents along with their effects on climate, navigation and marine life.
These notes are useful for UPSC, SSC, Railways, State PSC, CUET and CBSE Board Exams. The chapter is highly important for understanding oceanography, climatic influence of oceans and marine geography.
This chapter explains different movements of ocean water such as waves, tides and ocean currents. It highlights the role of physical forces like wind, gravity, temperature, salinity and the sun-moon system in influencing oceanic circulation and marine geography.
Ocean water is dynamic and continuously moving because of temperature, salinity, density differences, wind and gravitational pull of the sun and moon.
Waves represent movement of energy across the ocean surface. Water particles move in circular paths and water itself does not travel long distances.
Wind provides energy for wave formation.
Vertical distance between crest and trough.
Half of wave height.
Time interval between two successive crests or troughs.
Horizontal distance between two successive crests.
Rate of wave movement measured in knots.
Number of waves passing a point in one second.
Tides are periodic rise and fall of sea level mainly caused by gravitational pull of the moon and the sun.
Irregular water movements caused by winds and atmospheric pressure changes are called surges.
When tides move through bays, estuaries and between islands, they are called tidal currents.
Ocean currents are river-like flows of ocean water moving in definite directions.
Large circular systems of ocean currents are called gyres.
Warm currents moderate temperatures in North-West Europe.
Wind provides energy for wave formation.
The moon’s gravitational pull mainly causes tides.
Highest tides occurring when sun, moon and earth are in straight line.
Continuous flows of ocean water in definite directions.
Mixing of currents increases oxygen and plankton growth.