The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into tectonic plates. The Earth's lithosphere is composed of seven or eight major plates (depending on how they are defined) and many minor plates. Where the plates meet, their relative motion determines the type of boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually.[2]
Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the lithosphere remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories, since disproven, proposed gradual shrinking (contraction) or gradual expansion of the globe.[3]
Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.
Answer:
You need to put more info for the question
Explanation:
But thanks for the free points
The idea of global cooling gained popularity about during the 1970s, <span>“There are ominous signs that the earth’s weather patterns have begun to change dramatically,” </span>Newsweek reported in 1975. At the time the highly influential source convinced <span>“drastic decline in food production.”, at that time climate scientists were convinced that a ice age was coming. Global temperatures falling between 1940 to 1975 drove the concern of global cooling, little did they know it was only a temporary fall of temperature.
That's as much as I know, hope it helped! :)</span>
Answer:
Because of its rivers and topography containing Big rivers with hydroelectric potential
Explanation:
Summed up Hydroelectric power is obtained by the water flow moving turbines that generate electric power. This water is obtained from rivers with a high flow generally near mountainous regions, this kind of rivers is all over Europe because of its topography, the Alps and the Ural mountains are home of many hydroelectric plants taking advantage of the rivers flowing down. For example in Austria, the Danube River is used for obtaining Hydroelectric power.
Although the Hydroelectric plants are smaller compared to Asian or Canadian plants, hydroelectric power is still one of the main sources of energy for central Europe, countries like Spain, France, Netherlands, Sweden, Austria take advantage of their mountains and rivers running down them for building the hydroelectric plants.
It isn't exactly known who discovered it first, but the earliest claim of earth being round rather than flat was posed by Pythagoras sometime around 500 B.C. He argued that if the moon was round the Earth should be as well.
After that, his claim was proven true by a man named Anaxagoras at around 500-430 B.C when he brought up solar and lunar eclipses. The shape of Earth's shadow on the moon was also used as evidence that the Earth was round.
And finally, in 350 B.C the great Aristotle declared that the Earth was a sphere based on constellations you can see if you travel farther from the equator. Over the next hundred or so years, Aristarchus and Eratosthenes actually measured the size of the earth.
Short answer: The Greeks
