1. The Sun, Ocean, and the Water Cycle Unit 16

2. The Water Cycle The water cycle is the continuous movement of water through Earth’s environment. The main parts of the water cycle are: Evaporation Condensation Precipitation Collection

3. Interaction between the Sun and the Ocean Oceans hold 97% of Earth’s water. The sun heats the water in the ocean, causing evaporation. 86% of worldwide water evaporation comes from the ocean. 78% of worldwide precipitation happens over the ocean.

4. Evaporation Evaporation is the process by which a liquid changes to a gas. The water in oceans, lakes, and rivers is heated by the Sun. It is then turned to water vapor and then evaporates into the air. Transpiration is the process where plants return water vapor to the air.

5. Condensation Condensation is the change from gas to a liquid as a result of cooling. After water evaporates, the air cools and water vapor changes back into water droplets. The water droplets form clouds. When the water droplets become too heavy, precipitation occurs.

6. Precipitation Precipitation is ANY form of water falling from the clouds to Earth. When clouds become full of condensed water, the air is unable to hold the water anymore and the water falls to produce a form of precipitation. Rain, sleet, hail, and snow are all forms of precipitation.

7. Collection After any form precipitation occurs, the water either soaks into the ground or lands in the oceans, rivers, or lakes. Water that soaks into the ground is called groundwater. Runoff occurs when water from rain or melted snow flows along Earth’s surface into bodies of water.