THE WATER CYCLE – ITS KEY STAGES WITH COMPLETE PROCESS

The water cycle is the cyclical process by which water circulates between the earth and its atmosphere in a series of stages where water undergoes change of state from liquid to vapor and back to liquid. Water cycle is also known as hydrologic cycle.

Water cycle primarily occurs in five stages : evaporation, condensation, precipitation, runoff and percolation. It is driven by solar energy. The water cycle is of vital importance for sustaining life on earth by constantly replenishing available fresh water. It also plays crucial role in climate regulation and distribution of water required for agriculture and other activities.

STAGES OF WATER CYCLE

The water cycle includes five stages. These are : evaporation, condensation, precipitation, runoff and percolation.

EVAPORATION

Evaporation is the first step of water cycle. During evaporation, water from rivers and oceans is converted into water vapor after it gets heated up by the sun. Water vapor rises up in the air and moves from hydrosphere to atmosphere.

*Evaporation of water by plants is called transpiration, accounting for greater rainfall in forests.

*In cold regions, snow can directly turn into water vapor without melting into water. this is called sublimation.

CONDENSATION

As water vapor reaches high altitudes, it turns into tiny droplets of water. This happens because of low temperature at high altitude. These water droplets combine with various gases and dust particles to form clouds.

PRECIPITATION

When clouds become too heavy, they are unable to hold any more water. Clouds then release the water they contain in form of rain, hail or snow.

RUNOFF

As water falls over the surface of earth, it leads to runoff. Water again enters the hydrosphere.

PERCOLATION

Water seeps through the soil and is stored as ground water.

IMPORTANCE OF WATER CYCLE

• Replenishes freshwater supplies on earth.
• Participates in climate regulation.
• Distributes water across the ecosystem for agriculture and other essential activities.
• Transports minerals.
• Supports ecosystem by providing habitats such as rivers and wetlands.
• Helps in creation of landscapes such as valleys and rivers over time by shaping the earth’s surface through runoff and erosion.