Wind, as an external force, plays an important role in shaping coastal areas and steppes.
Within the lethal embrace of deserts, life can only flourish because of large springs. Here...
One third of the continents is covered with desert. Today, desertification is a growing problem.
Water is one of our key natural resources; we must protect it vigorously.
The rise and drop of sea levels caused by the gravitational force of the Moon.
A glacier is a large body of ice in constant, slow motion down a hillside.
The area surrounding an inactive or extinct volcano is not necessarily calm. Let’s see the...
The four outer planets (Jupiter, Saturn, Neptune and Uranus) do not have solid surfaces, thus...