From where comes the water?

To understand from where the water comes from, it is necessary to remember the physical states in which it appears:

Water in gas  state –  in the atmosphere,  coming from the evaporation of all  wet surfaces on the planet – oceans, rivers and lakes;

Water in liquid  state –  in  oceans (as salt water), rivers and lakes (sweet water) and inside the subsoil, that constitute the called ‘ground water’.

Water in solid state – in the cold regions of the planet, on the poles.

The water cycle

(TRADUÇÃO TABELA: Evaporation, Condensation, Rain and/or snow melting, Water  permeating in rocks and soils,  Rains at the oceans, Evapotranspiration of plants, Ground water)

All water on the planet keeps in constant movement,  shifiting from one state to another (solid, liquid or gas) . With  this   movement supporting  life on Earth. This is the so called ‘hidrologycal cycle’.  Up to 25%  from the rain water that falls on the planet’s surface doesn’t reach the soil, stopped at tree tops. . The remaining amount flows onto the soil or permeates  it. Around 1% of the rain water is  held to create organic material that forms  living beings. What hasn’t been used reachs the oceans, falls directly  onto them or arrive to the sea through water courses.  Human actions  interrupt this natural water cycle.  In  urban areas,  there is soil’s impermeability,  polution and absence of vegetation that also impact the cycle.