Oceans

Introduction:

Oceans are massive bodies of salt water constituting a principal part of the hydrosphere. Oceans cover more than 70% of the earth’s surface. Sea water in the oceans has a salinity of approximately 3.5%. Oceans also help regulate the earth’s climate and make life on Earth possible by distributing heat from the sun and absorbing carbon dioxide from the atmosphere. From the seashore to the deepest depths, oceans are home to some of the most diverse life on Earth.

Icebreaker: Throw the Globe

·         Have kids stand in a circle and throw an inflatable globe to one another. Every time someone catches the globe, have the recipient locate and identify one of the earth’s oceans.

Read Aloud: I Am the Ocean by Suzanna Marshak

Presentation Outline:

·         Oceans

o   Pacific Ocean

o   Atlantic Ocean

o   Indian Ocean

o   Antarctic Ocean

o   Arctic Ocean

o   Seas

·         Water

o   Salt Water vs. Fresh Water

o   Salt Water

§  Water Temperature

§  Water Pressure

§  Buoyancy

o   Waves

o   Tides

o   Currents

·         Layers

Activity: Experiments
  
Salt Water: Explain that oceans are comprised of salt water.

·         The objective of this experiment is to prove that sea water contains salt.

o   Fill a pot with sea water. Heat the pot on a stove until all the water has evaporated. Observe and taste the residue that remains in the pot.

o   Salt will be present in the pot.

o   Sea water is made up of both water and salt, so when the water is evaporated salt will still remain.

·         Discuss salt water

Water Temperature: Explain that warm water is less dense than cold water so it floats on top of it.

·         The objective of this experiment is to show what occurs when warm water and cold water collide in the oceans.

o   Fill a glass bowl ¾ full of cold water. Fill a pitcher with hot (but not boiling) water. Add a few drops of red food coloring to the pitcher of hot water. Gently pour the hot water in the pitcher into the bowl containing the cold water.

o   The red hot water will float on top of the uncolored cold water.

o   When water is warmed, the heat causes the water molecules to move faster and farther apart. As the molecules move farther apart, the water becomes less dense. Warmth makes water lighter, so it floats on top of the heavier, denser cold water.

·         Discuss water temperature

Water Pressure: Explain that pressure is exerted on submerged objects by water. 

·         The objective of this experiment is to show that pressure is exerted on objects immersed in water.

o   Secure the opening of a balloon to plastic tubing with rubber bands. Blow up the balloon. Then deflate the balloon. Submerge the balloon in a bucket filled with water. Try to blow up the balloon.

o   The balloon cannot be blown up while submerged in the water.

o   It is impossible to inflate the balloon while it is immersed in water because the water is exerting pressure on the balloon.

·         Discuss water pressure

Buoyancy: Explain that salt water is more buoyant than fresh water.

·         The objective of this experiment is to show that objects float more easily in salt water than in fresh water.

o   Fill a glass ½ full of warm water. Carefully place an egg in the glass. Add 1 tsp. of salt at a time to the glass.

o   The egg will be able to float in the salt water.

o   The salt in the water makes the water more buoyant because salt water exerts more upward force than regular water, which allows the egg to float.

·         Discuss buoyancy

Quiz: Sea What You Learned

1. Name all the oceans. (Pacific, Atlantic, Indian, Antarctic, Arctic)

2. Oceans are comprised of ____ _____. (salt water)

3. ____ water floats in the ocean as opposed to ____ water. (warm, cold)

4. Water pressure _________ as the ocean deepens. (increases)

5. Salt water is more _______ than fresh water. (buoyant)

6. A ____ is a forward motion of energy in water produced by wind. (wave)

7. _____ are the daily rise and fall of ocean waters caused by the earth's rotation and the moon's gravitational pull. (tides)

8. A _______ is like a highway or river of continuously moving water that travels great distances. (current)

9. Name all of the layers of the oceans. (Epipelagic Zone, Mesopelagic Zone, Bathypelagic Zone, Abyssopelagic Zone, Hadalpelagic Zone)

Craft: Ocean in a Bottle

Have kids create a model of the ocean in a plastic bottle using objects found on a beach along with oil and water.