2. The Water Cycle It’s role in weather.

3. What is a cycle? A series of events that happens over and over. A series of events that happens over and over. There isn’t a beginning. There isn’t a beginning. There isn’t an end. There isn’t an end.

4. Steps Of The Water Cycle Evaporation Evaporation Transpiration Transpiration Condensation Condensation Precipitation Precipitation Surface Runoff Surface Runoff Underground Runoff Underground Runoff

5. Evaporation Liquid turns into a gas. How? Heating the water. What does the heating? The sun.

6. Transpiration Do plants sweat? Sort of…people perspire (sweat), but plants transpire. This is the process by which plants lose water out of their leaves. How does this play a role in the water cycle? The water on the leaves evaporates into the air.

7. Condensation Gas turns into a liquid. Gas turns into a liquid. How? How? Cooling the gas down. Cooling the gas down. What does the cooling? What does the cooling? The lack of heat in the atmosphere at high altitudes. The lack of heat in the atmosphere at high altitudes. When water vapor (gas) condenses into a liquid it forms a cloud. When water vapor (gas) condenses into a liquid it forms a cloud.

8. Precipitation When water is in the form of a liquid, the molecules stick to one another. Sometimes, there are too many water molecules sticking together…a cloud becomes too heavy. What happens? The water molecules fall back to the Earth’s surface as rain, snow, hail, or sleet.

9. Surface and Underground Runoff What happens to the water when it reaches the Earth’s surface? What happens to the water when it reaches the Earth’s surface? Gravity causes the water to seep into the soil – Underground Runoff. Gravity causes the water to seep into the soil – Underground Runoff. The water flows over the land and into other bodies of water (i.e. lakes, rivers, ponds, the ocean) – Surface Runoff. The water flows over the land and into other bodies of water (i.e. lakes, rivers, ponds, the ocean) – Surface Runoff. Sometimes the surface runoff causes rivers & lakes to form. Sometimes the surface runoff causes rivers & lakes to form.

10. Food For Thought What is the #1 place where evaporation occurs? What is the #1 place where evaporation occurs? Our world’s oceans. Our world’s oceans. The oceans are salty, but rain isn’t. Why? The oceans are salty, but rain isn’t. Why? When the water evaporates it leaves the salt and other impurities behind. When the water evaporates it leaves the salt and other impurities behind. How much of Earth’s water is usable by humans? How much of Earth’s water is usable by humans? 0.3% is usable by humans. 0.3% is usable by humans.