The water cycle The water cycle
The Water cycle is also known as the hydrologic cycle. This is the name for the journey water takes as it makes its cyclic journey from the land to the sky and back to the land again.

The Earth

The Earth is covered by water. Almost 97% of this water is salt water found in the oceans.

Salt water is not suitable for use by humans as drinking water unless it goes through an extensive filtration treatment process. Humans are therefore reliant upon the remaining 3% of the earth’s water for their use as drinking water and for all other uses that require fresh water.

Heat From the Sun

Heat from the sun provides the energy to evaporate water from the oceans, rivers, lakes etc of the Earth’s surface. Water also comes from plants through transpiration.

Cloud Formation

This water from the Earth’s surface condenses and forms tiny droplets of water which form clouds. When the cool air from the land meets the clouds, precipitation, in the form of rain, snow or sleet is set in motion.

Water Returns to the Land

Some of this water soaks into the land and some returns as run off to the rivers and lakes. Some of the water becomes trapped between layers of clay or rock. This is then called groundwater.

The Six Steps of the Water Cycle

1. Condensation – When gas is turned into a liquid
2. Infiltration – When rain soaks into the ground
3. Runoff – when water runs off the land’s surface flowing downhill into rivers, lakes etc
4. Evaporation – where liquid, water, changes from the liquid state to the gaseous state
5. Precipitation - When small droplets of water in clouds form larger droplets, precipitation happens. The raindrops then fall to the land
6. Transpiration - where plants absorb water from the soil. Water moves from the roots to the leaves through the stems of the plant. When the water reaches the leaves, some of it evaporates. This adds to the amount of water vapor in the air. The process of evaporation through plant leaves is called transpiration.

Other great pages to visit in "Environment" are:

Floods, River; Pollution, River, Conservation, How Rivers Change, Threatened Rivers,

Some major rivers

Murray-Darling basin and the Amazon

Read More

Residential Towers

Rivers are very important.

Saving Water

Water is our most precious natural resource.