how does Plate tectonics affect mankind?

Answer 1

Short term...Volcanoes and earthquakes
Long term...Continental drift

Answer 2

Because you've asked this under the weather category, I'm going to give you a weather answer.

Plate tectonics cause the rise and fall of the land masses as they collide. These motions are typically accompanied by earthquakes (not a weather thing).

Where a plate (of land mass) is raised by the tectonics, we have mountains. Where a plate is lowered, it eventually disappears into the adjoining ocean if there is one. Otherwise, the plate simply disappears under the raised plate.

Plate tectonics can give us mountains by two means: lifting and volcanic action. Lifting is simply where the ground of the upper plate is lifted higher by the underlying plate. There are several kinds of lifting (e.g., folding, dome, and fault-block) named according to how the lifted part looks. The Himalayas and Rockies are prime examples of lifted mountains. [See source 1.]

Volcanic mountains result when two plates collide and result in releasing underlying magma (lava) and ash through cracks in the Earth's mantel. The Hawaiian Islands are examples of such volcanic mountains springing up from under the ocean where two plates are colliding.

So what do these have to do with weather...plenty. High mountains can lift air mass as it flows over the mountains. This lifting by mountains is called orthographic lifting. [See source 2.] When the air rises, it cools. As it cools, water in the air condenses. If enough water condenses, the air can no longer hold it and it rains (and/or snows).

So mankind is likely to find it wetter over the mountains than it is on the leeward (down wind) side of them. Orthographic lifting is one major player in creating desert like conditions on the leeward side of mountain ranges. There are other players (like ocean currents) to be sure, but the mountains are a major one for creating excessivly wet and dry parts of the world.

Volcanic effluents (ash and gases) also affect our weather. For example, some major eruptions have been blamed for lowering the average temperature of the Earth by half a degree F. That effect lasted for about three years. [See source 3.]

There are other, non weather, effects that affect mankind. If you are interested, post your question elsewhere.

Answer 3

Plate tectonics (from Greek τέκτων, tektōn "builder" or "mason") is a theory of geology developed to explain the observed evidence for large scale motions within the Earth's crust. The theory encompassed and superseded the older theory of continental drift from the first half of the 20th century and the concept of sea floor spreading developed during the 1960s.

The outermost part of the Earth's interior is made up of two layers: the lithosphere comprising the crust and the rigid uppermost part of the mantle. Below the lithosphere lies the asthenosphere which is a more viscous zone of the mantle. Although solid, the asthenosphere has very low shear strength, and can flow like a liquid on geological time scales. The deeper mantle below the asthenosphere is more rigid again.

The lithosphere essentially floats on the asthenosphere. The lithosphere has broken up into what are called tectonic plates - in the case of Earth, there are ten major and many minor plates. These plates move in relation to one another at one of three types of plate boundaries: convergent, divergent, and transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along plate boundaries. The sideways movement of the plates is typically at a speed of several centimetres per year.

Continental drift was one of many ideas about tectonics proposed in the late 19th and early 20th centuries. The theory has been superseded by and the concepts and data have been incorporated within plate tectonics.

By 1915 Alfred Wegener was making serious arguments for the idea with the first edition of The Origin of Continents and Oceans. In that book he noted how the east coast of South America and the west coast of Africa looked as if they were once attached. Wegener wasn't the first to note this (Francis Bacon, Benjamin Franklin and Snider-Pellegrini preceded him), but he was the first to marshal significant fossil and paleo-topographical and climatological evidence to support this simple observation. However, his ideas were not taken seriously by many geologists, who pointed out that there was no apparent mechanism for continental drift. Specifically they did not see how continental rock could plow through the much denser rock that makes up oceanic crust.

Wegener's vindication did not come until after his death in 1930. In 1947, a team of scientists led by Maurice Ewing utilizing the Woods Hole Oceanographic Institution’s research vessel Atlantis and an array of instruments, confirmed the existence of a rise in the central Atlantic Ocean, and found that the floor of the seabed beneath the layer of sediments consisted of basalt, not granite which was common on the continents. They also found that the oceanic crust was much thinner than continental crust. All these new findings raised important and intriguing questions. [2]

Beginning in the 1950s, scientists including Harry Hess, using magnetic instruments (magnetometers) adapted from airborne devices developed during World War II to detect submarines, began recognizing odd magnetic variations across the ocean floor. This finding, though unexpected, was not entirely surprising because it was known that basalt -- the iron-rich, volcanic rock making up the ocean floor-- contains a strongly magnetic mineral (magnetite) and can locally distort compass readings. This distortion was recognized by Icelandic mariners as early as the late 18th century. More important, because the presence of magnetite gives the basalt measurable magnetic properties, these newly discovered magnetic variations provided another means to study the deep ocean floor. When newly formed rock cools, such magnetic materials recorded the Earth's magnetic field at the time.

As more and more of the seafloor was mapped during the 1950s, the magnetic variations turned out not to be random or isolated occurrences, but instead revealed recognizable patterns. When these magnetic patterns were mapped over a wide region, the ocean floor showed a zebra-like pattern. Alternating stripes of magnetically different rock were laid out in rows on either side of the mid-ocean ridge: one stripe with normal polarity and the adjoining stripe with reversed polarity. The overall pattern, defined by these alternating bands of normally and reversely polarized rock, became known as magnetic striping.

When the rock strata of the tips of separate continents are very similar it suggests that these rocks were formed in the same way implying that they were joined initially. For instance, some parts of Scotland and Ireland contain rocks very similar to those found in Newfoundland and New Brunswick. Furthermore, the Caledonian Mountains of Europe and parts of the Appalachian Mountains of North America are very similar in structure and lithology.

[edit]
Floating continents
The prevailing concept was that there were static shells of strata under the continents. It was early observed that although granite existed on continents, seafloor seemed to be composed of denser basalt. It was apparent that a layer of basalt underlies continental rocks.

However, based upon abnormalities in plumb line deflection by the Andes in Peru, Pierre Bouguer deduced that less-dense mountains must have a downward projection into the denser layer underneath. The concept that mountains had "roots" was confirmed by George B. Airy a hundred years later during study of Himalayan gravitation, and seismic studies detected corresponding density variations.

By the mid-1950s the question remained unresolved of whether mountain roots were clenched in surrounding basalt or were floating like an iceberg.

Answer 4

some people believe there is an electro-magnetic charge generated when the plates rub together- and this electrical charge can affect people

Answer 5

We would know...except this is the weather category.

Answer 6

shake, rattle and roll

Answer 7

EarthQUAKES!