Earth tide or body tide is the small (<1 metre) motion of the Earth's surface at periods of about 12 hours and longer. The motion is caused by the gravity of the Moon and Sun. The largest body tide constituents are semi-diurnal, but there are also significant diurnal, semi-annual, and fortnightly contributions. Though the gravitational forcing causing earth tides and ocean tides is the same, the responses are quite different.
Read more about Earth Tide: Tidal Forcing, Body Tide, Other Earth Tide Contributors, Tidal Constituents, Earth Tide Effects
Famous quotes containing the words earth and/or tide:
“All you of Earth are idiots!... First was your firecracker, a harmless explosive. Then your hand grenade. They begin to kill your own people a few at a time. Then the bomb. Then a larger bomb, many people are killed at one time. Then your scientists stumbled upon the atom bomb—split the atom. Then the hydrogen bomb, where you actually explode the air itself.”
—Edward D. Wood, Jr. (1922–1978)
“the tide lays down its wet throat
and alters the land to island—even as I watch
I say there is no shore
apart from stories of it,
no smoke, no hut, no beacon ...”
—Lynn Emanuel (b. 1949)