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Atmospherical nitrogen is bound by bacteria and used by living organisms in the form of...
Cold and warm fronts are formed where bodies of cold and warm air meet.
Did you know that about 75% of the land on our planet is covered with sedimentary rock?
This video presents the different stages of coal formation.
Fog is a type of cloud that forms close to the surface of the Earth. There are places on the...
Above a certain altitude snow does not melt, not even in summer.
Water covers about 71% of the Earth’s surface. But why are there two types of water on Earth,...
On a geological time scale lakes are short-lived.