This document discusses ocean currents. It begins by introducing the group members and listing the contents to be covered, which include the causes of ocean currents, types of currents, their strength, dangerous currents, and importance. The causes section explains that currents are formed by the moon's gravity, winds, density differences, and occasional events. The types section describes surface/gyre currents and deep ocean currents. Strength depends on various atmospheric and oceanographic factors. Dangerous currents include rip currents near sandbars, currents alongside structures, and longshore currents moving parallel to shorelines. In conclusion, the importance of currents is that they affect weather, climate, marine life, Earth's features, and energy generation.

2. GROUP MEMBERS
Maheen Raza
Qurat-ul-Ain Ali
Nida Najabat

3. CONTENTS
•INTRODUCTION
•CAUSES OF FORMATION OF OCEAN CURRENTS
•TYPES OF OCEAN CURRENTS
•STRENGTH OF OCEAN CURRENTS
•TYPES OF DANGEROUS CURRENTS
•IMPORTANCE OF OCEAN CURRENT

4. INTRODUCTION
•Permanent or continuous directed movement of water
•Vertical and horizontal movement
•Vary in size and strength
•Warm ocean current and Cold ocean current
•California currents in Pacific, Gulf stream, Indian
monsoon current in Indian ocean

5. CAUSES OF FORMATION OF OCEAN
CURRENTS
 Moon’s gravitational pull
• Gravitational attraction forms tides
• Falling and rising of tides forms currents
• Known as Tidal currents
• Found in bays and near shores
• Have regular pattern

6.  Wind
•Stress of wind in upper layer of water
•Winds drive current near coastal area on a localized scale
•Winds drive current in open ocean on a global scale

7.  Density Difference
•Depends upon temperature and salinity
•Less dense heated water moves above cold water
•Gives off heat, cools and sinks
•Thermohaline circulation
•Transport oxygen, heat and nutrients

8.  Occasional Events
•Huge storms
•Underwater earthquake Tsunamis

9. TYPES OF OCEAN CURRENTS
1) Surface current (Surface circulation)
•Make about 10% of all ocean water
•Upper 400m of ocean
•Solar heating, winds and gravity
•Circular pattern (gyres)
•Coriolis effect (deflection of air due to rotation of earth)

10. •Clockwise spirals in northern hemisphere
•Anticlockwise spirals in southern hemisphere
•Deep and narrow or shallow and wide
•Carry heat so affect regional climates
•Eddies (swirling loops of water)
•Example : GULF STREAM

11. 2) DEEP OCEAN CURRENTS
•Make 90% of worlds ocean
•Formed due to temperature, salinity and density difference
•Global convey best (constantly moving system of deep ocean
driven by temperature and salinity difference )
•Submarine river (flow under surface of oceans)
•Very slow and hidden from immediate detection
•1000 years to complete one full circuit of globe

12. STRENGTH
•Wind speed
•Precipitation
•Shape of ocean floor
•Evaporation
•Inflow from river and adjacent seas

13. TYPES OF DANGEROUS CURRENTS
1) Rip currents
• Waves break over a sand bar near shoreline
• Water gets trapped between sandbar and shore
• Water releases pressure by returning back to lake in
form of rip current
• Powerful and hazardous for swimmers

14. 2) Structural Currents
•Found alongside structure like break walls
•Dangerous
•Washing machine effect
•Swimmers moved back to lake with no path

15. 3) Long Shore Currents
• Move parallel to or along shoreline
• Exert force to move along shore

16. IMPORTANCE OF OCEAN CURRENT
•Absorb moisture and heat so determine weather system
•Transport cold and warm water so determine climate
•Maintain marine life by circulating nutrients
•Shapes the features of earth
•Marine power generation