2. Importance of Water
If there was no water, there would be no life
Why is water important?
1) The first life on earth came from water
2) All organisms depend on water to survive
A human can live only 3 or 4 days without water!!!
3. How Much Water is There?
Water covers 71% of the earth’s surface
Where is water found?
1) Oceans 96.5%
2) Groundwater 1.7%
3) Glaciers 1.7%
4) Lakes about 0.09%
5) Vapor, clouds, precipitation 0.001%
4. How Much FRESHWATER is There?
Freshwater is water without salt; the Chao Praya river is
freshwater
Only 2.5% of the earth’s water is freshwater, the rest is
saltwater from the oceans
99% of the earth’s freshwater is groundwater or ice
(snow), 0.3% is in lakes and rivers, and the rest is in
animals
5. THE WATER CYCLE
• Water in oceans, lakes rivers
or on land evaporates into the
air.
• It then turns into rain and falls
back to the earth and the
process begins again…….
6. WATER VAPOR
• Water vapor is water
molecules in the air
• Steam and clouds
are both forms of
water vapor
12. QUESTIONS (2 Points Each)
1. Draw a picture showing water evaporation,
condensation and precipitation.
2. Is there water vapor all around you right now?
3. When you have a cold drink, is it precipitation that forms
on the cup, or condensation?
4. Explain in your own words why water forms on the
outside of a cold cup.
5. Raindrops need to form on something in the air to make
precipitation. What does the water vapor condense
onto??
