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A geyser is a spring characterised by intermittent discharge of water and steam.
This animation demonstrates different types of volcanic eruptions
This video presents the different stages of coal formation.
Developed nearly 500 years ago, it is a variant of the Julian calendar. Today it is the most...
Above a certain altitude snow does not melt, not even in summer.
Tsunami waves are very high waves of immense destructive power.
The duration of solar radiation, the angle of the Sun's rays and the surface albedo all have an...
Lightning is a sudden electrostatic discharge accompanied by a sound known as thunder.