water cycle

The water cycle (also known as the hydrologic cycle) is the journey water takes as it circulates from the Earth to the sky and back again.


Most waves are caused by the wind.



Alfred Lothar Wegener (1880-1930), the German geologist and meteorologist, proposed the theory of continental drift in his 1915 book, On the Origin of Continents and Oceans. This theory states that parts of the Earth's crust slowly drift atop a liquid core. The fossil record overwhelmingly supports and gives credence to the theory of continental drift (and that of plate tectonics). He proposed the existence of the supercontinent Pangaea, and named it (Pangaea means "all the land" in Greek). Wegener froze to death while heading an expedition crossing the Greenland ice cap in 1930.


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