DBH 3.
BIOLOGY & GEOLOGY
The Energy that shapes the Earth´s surface
The Earth is a dynamic planet; in other words, it undergoes constant changes that affect its three layers (atmosphere, hydrosphere and geosphere.
The energy that drives the changes on the Earth comes from internal heat of the planet, gravity and the Sun.
1. THE INTERNAL ENERGY OF THE PLANET.
The interior of the Earth is very hot. The internal energy, also called, geothermal energy, means that the materials of the mantle are soft, move slowly and push against the Earth´s crust.
The transformation of energy into movement is similar to what we can observe when we heat chocolate in a pan (the chocolate nearest the bottom heats up more, becomes less dense and rises).
2. ENERGY DUE TO GRAVITY.
Due to its mass, the Earth exercises a force which attracts objects towards its centre. This force is called gravity, which causes things to fall and this is the reason why the continental waters flow down towards the sea.
3. ENERGY FROM THE SUN.
They Sun sends a large quantity of energy to the Earth in the form of light and heat, which warms up the surface of the Earth. As a result, the air in contact with the surface heats up and the surface water changes state (the ice melts and the liquid water evaporates).
As the Earth is spherical and has an inclined axis of rotation, the Sun´s rays hit the different regions of the Earth´s surface at different angles. These variations cause the seasons.
ACTIVITIES
Search for new vocabulary and build up a particular section of related vocabulary.
1. Name the main forms of energy that are responsible for the changes on the Earth´s surface and explain the origin of each one of them.
2. Explain why different places on the Earth´s surface receive different quantities of solar energy.
3. Worksheet I.
ENERGY AND GEOLOGICAL PROCESSES.
The processes that modify the surface of the planet, called geological processes, are due to the energies describes above:
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Internal energy is responsible for changes on the Earth´s surface sucha as the deformation of rocks, earthquakes, volcanoes, etc. These changes are the so-called endogenous geological processes.
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Gravity and solar energy drive the dynamics of the atmosphere and the hydrosphere, which change the Earth´s surface due to the action of the wind, water and ice. They are the exogenous geological processes.