Friday, 7 February 2014

Oceans: A world full of currents


 5.2.14 Today's Subject: Oceans

 Basic Knowledge:

  • Oceans provide about 30% of our protein.  It’s salty.  It’s saltwater.You can’t drink it.The ocean is about ~70 % of the Earth’s surface.There are many currents.There are many types of plants and animals.It’s always moving. Sometimes, sewage and garbage is dumped into the ocean.

1. Names of oceans
  • Atlantic
  • Pacific
  • Indian
  • Arctic
  • Southern (Antarctic)
2. Names of big seas
  • Mediterranean 
  • Caribbean


 

The way water moves:

Temperature:



  • Water heats up at the equator and stays on the surface. It flows to cooler regions.
  • Water cools at the poles and sinks (because cool water is denser) and flows to warmer regions.
Red died water warmer and that is why it is on top. The lamp represents the sun which warms up the water with the red die which is less dense than the cooler water that has blue die and is at the bottom.

Sketch: World 



Global Winds:



2) Global Winds
Winds are the main source of movement for surface ocean currents.  Wind passing over ocean, through friction, causes the ocean to move.
 
Atlantic

 


Pacific



Indian

 

Southern

 


Arctic





Coriolis Effect:



  • The Earth spins on its axis.  Fluids (the atmosphere and the oceans) will be deflected by its spin.  
  • Currents in the northern hemisphere tend to move clockwise.
  • Currents in the Southern Hemisphere tend to move counterclockwise.

Current:


4) Surface Currents
  • The animation is a summary of satellite data from NASA tracking all the surface currents.  This video shows the details of all the currents.  Look at the patterns to try to figure out the global currents.
Video of NASA: Perpetual Ocean



  • North Atlantic, clockwise
  • South Atlantic, counterclockwise
  • Indian, counterclockwise
  • North Pacific, clockwise
  • South Pacific, counterclockwise
  • Antarctic Circumpolar, clockwise 

No comments:

Post a Comment

Please write positive comments or constructive feedback in full sentences.