Deutsch: Wasser / Español: Agua / Português: Água / Français: Eau / Italiano: Acqua
Water is a liquid at normal temperatures but exists also solid (ice), and water vapor (cloud) in the air.
A water molecule has the formula H2O which means that two hydrogen (H) atoms and one oxygen (O) are connected.
The Earth's surface is covered with water for about 71%. It is necessary (vital) for nearly all forms of life on Earth.
The distribution of water is roughly
- 96.5% in seas and oceans,
- 1.7% in groundwater,
- 1.7% in glaciers and the ice caps of Antarctica and Greenland
- The rest is in the air as moisture, clouds and precipitation
From all this water, only 2.5% is freshwater and from this 98.8% of that water is in ice and groundwater.
0.3% of all freshwater (0.0075% of all water) is in rivers, lakes, and the atmosphere.
Freshwater is permanently moved by
- evaporation and transpiration (evapotranspiration),
- condensation and
Access to safe drinking ressources is essential for all (not only human) forms of life on Earth.
List of books: Water