An infographic to help you understand the water cycle
The main stages
70% of the
earth’s surface is covered by water. For more than 4 billion years the same
water has been circulating and undergoing constant transformations. It forms
what’s called the water cycle, driven by solar energy.
Evaporation:
Water from oceans, rivers and lakes is transformed under the action of the
sun’s heat into vapour and evaporates into the atmosphere.
Condensation:
In the atmosphere, the water vapour comes into contact with cold air and
condenses, forming tiny droplets which then create clouds.
Precipitation:
Once in the clouds, water which becomes too heavy to remain suspended is
transformed into rain, snow or hail. Most precipitation occurs directly over
the Oceans. On average, a water molecule remains in the atmosphere for 8 days
before falling on the continents.
Surface
runoff: Part of the water flows along the ground and directly into water
courses (rivers, streams, etc.) and eventually into the Ocean. A drop of water
remains in a river for an average of 2 weeks before reaching the Ocean.
Storage:
Water which is not in water courses may become stored in lakes or ponds. On
average, it is stored there for 17 years.
Infiltration: Water which has not flowed into rivers or become stored infiltrates the soil and becomes groundwater.
