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Water, water, everywhere, nor any drop to drink" - Photos taken from space looking back at the Earth reveal that the Earth is over 70% covered by water, most of which is in the oceans. So, how much of this 70% is useable to humans as fresh water? Think about all of the water that is on the Earth…… Where is this water? Is this water available for human use? Record your thoughts in a journal. Share your thoughts with others in a small group and in your class. Make a list of all the places where water is found.

EQ: How much of the water on Earth is available for human use?

•Most of the world’s water is salt water found in the oceans

•Some of the world’s water is found in glaciers and polar ice caps

•Some of the world’s water is fresh water that is unavailable due to pollution or inaccessibility

•Lastly, some of the world’s water is potable fresh water. This is found in lakes, rivers, streams, underground, and in reservoirs.

Goal iGoal in this lab activity … 

Learn that water is a limited resource.

Let’s Investigate …Let’s Investigate … Predicting the Amount of Water Found on Earth

Water on Earth is found in the oceans as salt water, in glaciers and polar ice, and as surface and ground water. Predict how much water of each type is found on the Earth.

•Color the percent of salt water green. •Color the percent of fresh water in glaciers and polar ice caps yellow.•Color the fresh water found on the surface and in the ground blue. •Color the amount of fresh water available for human use red.Then I will model the amount of water found on the Earth as salt water, fresh water in glaciers and polar ice caps, and fresh water on the surface and in the ground. Use the right side of the chart below to color in the actual data.

Prediction Actual

Percent of Each Type of Water Found on Earth

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90

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10

0

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90

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Salt Water

Fresh Water in Glaciers and

Polar Ice Caps

Fresh Water on the Surface and

Under the Ground

Fresh water for human

use.

Important lessons of this activity:      Fresh water available for human use is limited in supply.       The world’s water can be found as follows: o       97% of the world’s water is salt water found in the oceanso       2.4% of the world’s water is found in glaciers and polar ice capso       1.6% of the world’s water is fresh water that is unavailable due to pollution or inaccessibilityo       About 0.00003% (3/100,000) of the world’s water is portable fresh water. This is found in lakes, rivers, streams, underground, and in reservoirs.

 

Question 1: What can you conclude from this activity?

Question 2: Do you think the amount of water on Earth has remained constant since Earth was first formed? Will the amount of water stored in the oceans, glaciers and ice caps, streams and underground, and in the atmosphere change in the future? Why or why not? 

Water Facts of LifeRide the Water Cycle With These Fun Facts

•There is the same amount of water on Earth as there was when the Earth was formed. The water from your faucet could contain molecules that dinosaurs drank. •Water is composed of two elements, Hydrogen and Oxygen. 2 Hydrogen + 1 Oxygen = H2O. •Nearly 97% of the world’s water is salty or otherwise undrinkable. Another 2% is locked in ice caps and glaciers. That leaves just 1% for all of humanity’s needs — all its agricultural, residential, manufacturing, community, and personal needs. •Water regulates the Earth’s temperature. It also regulates the temperature of the human body, carries nutrients and oxygen to cells, cushions joints, protects organs and tissues, and removes wastes. •75% of the human brain is water and 75% of a living tree is water. •A person can live about a month without food, but only about a week without water. •Water is part of a deeply interconnected system. What we pour on the ground ends up in our water, and what we spew into the sky ends up in our water. •The average total home water use for each person in the U.S. is about 50 gallons a day. •The average cost for water supplied to a home in the U.S. is about $2.00 for 1,000 gallons, which equals about 5 gallons for a penny. •Water expands by 9% when it freezes. Frozen water (ice) is lighter than water, which is why ice floats in water.