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On a geological time scale lakes are short-lived.
The Sun's rays travel through space without interruption, but once they reach the Earth's...
A glacier is a large body of ice in constant, slow motion down a hillside.
When masses of cold and warm air meet, weather fronts develop.
The area surrounding an inactive or extinct volcano is not necessarily calm. Let’s see the...
Lightning is a sudden electrostatic discharge accompanied by a sound known as thunder.
Physical properties, as well as the flora and fauna of the ocean change with depth.
This animation demonstrates different types of volcanic eruptions