The Water Cycle

The water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth. It is driven by the sun's energy and includes processes such as evaporation, condensation, precipitation, and runoff.

Key Processes of the Water Cycle

1. Evaporation: This is the process where water from bodies of water, such as oceans, rivers, and lakes, gets heated by the sun and turns into water vapor, which rises into the atmosphere.
2. Condensation: As water vapor rises, it cools and condenses to form clouds in the atmosphere.
3. Precipitation: When the condensed water droplets in the clouds become too heavy, they fall back to the Earth as rain, snow, sleet, or hail.
4. Runoff: After precipitation, water flows over the land surface, eventually making its way back to bodies of water or into the ground.

Importance of the Water Cycle

The water cycle is crucial for maintaining the Earth's water balance and supporting life on the planet. It replenishes freshwater sources, sustains ecosystems, and helps regulate the Earth's temperature.

Study Guide for the Water Cycle

Questions:

1. What drives the water cycle?
2. What is the process by which water turns into water vapor?
3. Describe the formation of clouds in the atmosphere.
4. What are the different forms of precipitation?
5. Explain the significance of the water cycle for life on Earth.

Activities:

• Observe and record the changes in a small bowl of water left in the sun over a few hours to understand evaporation.
• Create a mini water cycle in a terrarium or a sealed plastic bag to demonstrate the processes of condensation and precipitation.
• Research and present a case study on the impact of human activities on the water cycle and potential solutions to mitigate these effects.