The hydrological cycle is a natural process that keeps water in constant transition between the Earth's surface and the atmosphere, driven mainly by gravity, solar radiation and the inclination of the planet Earth. In this cycle the water goes through a constant process of evaporation, capture by the clouds and precipitation, when the water returns to the land.
On a global scale, the amount of water evaporated is equal to the amount of precipitated water, but this is a general statement, because in some regions the amount of water evaporated is greater than the amount of precipitate and vice versa.
