1. It’s more than a free drink Water conservation, budget, and the water cycle

2. Overview Water is continually moved around the earth. Name some words associated with the movement of water – where do you know these from? Nature and humans affect the water budget of an area and can be in need of water supply.

3. The Water Cycle

4. What is a water budget? A water budget is the amount of water “coming in” versus “going out” in a given area (also called the local water budget). As a whole, the Earth’s budget is balanced. Specific areas of the earth may have too much or too little in their budget – what evidence is there to show which is true for any area?

5. Conservation Saving water (certainly not from extinction) for human use is an ongoing issue. Think of how many ways water is used. What if we did not have water to do these things? After the demonstration, how much water dripped from the bottle in 1 minute? Imagine if this continued for 1 day – how much water would be lost?

6. Water conservation methods Not all water can be used effectively by humans – too many other minerals are present in much water on the earth. Local pollution laws are usually enacted to protect the fresh water supply of an area. Desalination, or the removal of salt from water, is a method currently being researched.

7. Words in this section Now read pages 243-246. The following words will appear. Desalination, water budget, precipitation, water cycle, evapotranspiration, runoff, groundwater, condensation.