The Water Cycle


The water cycle (also known as the hydrologic cycle) is a process that water goes through, between land, sea and atmosphere. During this cycle, the water changes into a liquid, solid and gas and is recycled through the process. Water is important for many things like marine life, farms and the industry. The water cycle consists of four main stages; Evaporation, Condensation, Precipitation and Runoff.


The first stage called evaporation, is when the heat from the sun heats up the water from lakes and oceans and turn all the liquid into the gas called water vapour. Plants and animals also release moisture into the air, this is called transpiration. Evaporation is more effective when the temperature is more high, because the hotter the sun, the greater amount of water vapour produced. Furthermore, the amount of water vapour in the air is called humidity, when warm air containing a lot of vapour moves into a space with colder air, the water condenses back into liquid and creates fog. Remember that it is an invisible process that changes any form of precipitation back into water vapour, which then floats up towards the atmosphere. This is when the condensation and precipitation stage begins.

Condensation & Precipitation

In these two stages, the water vapour created by the sun floats all the way to the cold atmosphere where it collides with dust and turns back into water, creating clouds. Eventually, the clouds will get too big, and the water droplets will start to fall, this is called precipitation. Precipitation may fall as hail, sleet, snow or in other forms. The way the clouds form are from tiny particles called aerosols, as the temperature cools, the water vapour turns back into either ice crystals or tiny water droplets. Eventually, the water droplets will start to stick and collide with the aerosols, creating tiny clouds.Also the amount of precipitation that falls from the sky differ depending on the location; some places hardly rain while others rain almost every day. When the precipitation lands near land, the next stage called runoff begins.

Runoff & Infiltration

Runoff is when precipitation flows into rivers and oceans, and seeps into the ground which is called infiltration. Runoff is infiltration that didn’t seep into the ground or did not evaporate. Only 35% of precipitation make it to the sea, the rest get infiltrated or evaporated. The rate of infiltration depends on the amount of rain, the type of soil, the saturation, etc….


Overall the water cycle is a never-ending process that recycles using the four main stages: evaporation, which evaporates water from the sea and rivers into water vapour, condensation, where water vapour forms clouds, precipitation, where water falls from the sky in form of rain, snow, sleet, etc…. And runoff where the precipitation flows into rivers and oceans