Question

1. What are three things that water variability affects for us?

Answer 1

1. Drought period - in time periods where there is more precipitation there is more water availability, and when there's not there isn't.
Floods - when there are floods there is much more water available.
Population density - in places with more population there is a greater need for water supply, while in places where there is lesser people, the water supply can be smaller.
2. The land, air, and water are heated each day by the sunlight. The heat produced by the sun that hits the earth as the earth rotates is then part kept by the atmosphere that doesn't permeate all of that heating energy.
3. By evaporation. As the sun heats the ocean, there is evaporation. As the ocean moves around with its tides there is also loss of water to the air. Also by the waves and winds there is water that's lost to the air.
4. Part of that vapour will be reabsorbed by the ocean because it cools and precipitates into the ocean. Other part of it is taken with the wind to land or to upper spheres of the atmosphere.
 5. Part is reabsorbed but other part isn't. The other part is taken by the wind. As a gradient, there is less water in the air then in the ocean, keeping it above the ocean.
6. There is more water in the oceans then on the land. Water remains in the air on average about 9-10 days.
7. --------
8. An average American family uses about 300 gallons of water.
9. About 22%.
10. About 27%.