The Water Cycle
What Is the Water Cycle?
The water cycle is the continuous movement of water through the atmosphere, land, and living organisms. It ensures a constant supply of fresh water for ecosystems.
💡 Key Concept: Water is recycled, not created or destroyed.
Main Stages of the Water Cycle
1️ Evaporation
✔ Water from oceans, lakes, and rivers is heated by the sun and turns into water vapour.
2️ Transpiration
✔ Plants release water vapour from their leaves into the air – part of evapotranspiration.
3️ Condensation
✔ Water vapour cools in the atmosphere and condenses into clouds.
4️ Precipitation
✔ Water falls back to Earth as rain, snow, sleet, or hail.
5️ Collection / Run-off
✔ Water collects in rivers, lakes, and oceans.
✔ It also soaks into the ground (infiltration) and moves through soil and rocks.
Role of Living Organisms
Organism | How It Affects the Cycle |
Plants | Transpire water from leaves into the atmosphere |
Animals | Drink water and release it via sweat, urine, or breathing |
Decomposers | Release water back to the environment as they break down dead material |
Why Is the Water Cycle Important?
✔ Maintains fresh water supplies
✔ Helps regulate climate and temperature
✔ Supports plant growth through transpiration
✔ Ensures the availability of water for all living things
💡 Water is a finite resource, so recycling it is essential for life on Earth.
Questions
- What process turns liquid water into vapour?
- What is transpiration?
- What happens during condensation?
- What forms of precipitation can occur?
- Why is the water cycle important for plants?
Summary
- The water cycle recycles water between land, air, and living things.
- Key processes: evaporation, transpiration, condensation, precipitation, and run-off.
- It ensures the availability of fresh water and supports life on Earth.