Continental Drift, Plate Tectonics, and their Unseen Impact on Earth

For centuries, scientists held the belief that the continents were fixed in their places. About a hundred years ago, however, someone came along to completely revolutionize this and set a foundation for the theory of plate tectonics.

This man was Alfred Wegener, a German meteorologist who observed that many of the continents seem to fit together like puzzle pieces. For example, the coasts of South America and Africa are like a newspaper page ripped roughly down the middle. Furthermore, Wegener discovered that rock formations and fossils in these areas and others of the colossal continental puzzle match up in surprising ways. The main pieces of fossilized evidence for continental drift are the mesosaurus and glossopteris, a lizard-like freshwater animal and a fern found as fossils across continents with no means of being easily transferred.

There was only one problem with this theory, which Wegener termed ‘continental drift’: he had no mechanism for movement--that is, Wegener lacked an explanation for the ‘drift.’ He hypothesized that the continents floated on the ocean, which is a laughable suggestion even today.

However, all of the evidence for continental drift still applies to a new theory, developed around the 1960’s: that of plate tectonics. This idea elaborates on continental drift, providing both new evidence and a mechanism for movement. Plate tectonics shows that the lithosphere is broken into pieces. These plates ‘float’ on the denser asthenosphere (the lower mantle). Recent advances in science, such as sonar and satellite data, have allowed scientists to view the earth and its plates in new ways. Revolutionary imaging techniques let us see that the age of oceanic crust increases farther away from divergent boundaries (where two plates move away from one another)--young oceanic crust forms at these borders. Another piece of evidence is ‘magnetic striping,’ which shows that the earth’s magnetic field reverses every few million years and the iron in new crust formed at divergent boundaries conforms to its direction.

There are other, more obvious effects of plate movement: they cause both volcanoes and earthquakes. One of the most devastating (and least recognized) volcanic eruptions ever recorded occurred on April 9th of 1815, when the Tambora volcano erupted over Indonesia. Though some of the ramifications were immediately obvious--a “death toll was around 100,000 people from the thick pyroclastic flows of lava; the tsunami that struck nearby coasts; and the thick ash that blanketed Southeast Asia’s farmlands, destroyed crops, and plunged it into darkness for a week”--others were more lasting, and have only recently been investigated properly (D'arcy Wood, 2014).

For several years following the Tambora eruption, the land was plagued by drought, disease, floods, and famine, but this was just the beginning. The gases released in the eruption went on to interfere with the Indian monsoon, give rise to a new, deadly strain of cholera (which “shaped the 19th century like no other calamity” as it spread across the globe), force disaster on Chinese farmers so extreme that they sold their children before turning to opium as a crop of choice, cause ‘the year without a summer’ and the ‘Panic of 1819’ (both of which impacted the US), and melt enough sea ice around Greenland and the Arctic that the British could found the age of polar exploration (D'arcy Wood, 2014)...  And this massive impact was all rooted in an innocent plate boundary in the East Indies. What if something like this were to happen again? Another eruption that would be remembered for centuries to come…

Bibliography

D'arcy Wood, G. (2014, April 9). One of the Most Devastating Volcanic Eruptions in Human History Just Got Even Worse. Retrieved April 17, 2014, from http://www.slate.com/articles/health_and_science/science/2014/04/tambora_eruption_caused_the_year_without_a_summer_cholera_opium_famine_and.html

http://discovery.yukozimo.com/media/o/3750-2.jpg

http://eatrio.net/wp-content/uploads/2013/01/8.-pangea_07sep2007.jpg

http://cookwilkie11.wikis.birmingham.k12.mi.us/file/view/magnetstripes2.jpg/294996626/magnetstripes2.jpg

Age of earth's oceanic crust (in millions of years) [Digital image]. (n.d.). Retrieved April 26, 2014, from http://media-2.web.britannica.com/eb-media/84/99284-004-1976F092.jpg

Earth's History

Earth formed roughly 4.6 billion years ago as a molten sphere of rock clouded with “choking fumes” (Appenzeller 2006). With time, the young planet cooled, and, as it became more hospitable, life slowly emerged, triumphing over several extinctions in order to achieve its current state of a flourishing, diverse environment. Earth is at an ideal distance from the sun, so that it retained water while it cooled; water is a critical ingredient in life. Three point eight billion years ago, the first life emerged as photosynthesizing cyanobacteria. It took another 3.256 billion years until the Cambrian explosion, the time period where most fossils originate from. With the beginning of the Paleozoic era came a time of dramatic geological, climatic, and evolutionary change. Interspersed with various advancements in the sophistication of life were five extinctions--the Ordovician (445 million years ago), Late Devonian (360 million years ago), Permian (251 million years ago), Triassic (205 million years ago), and K-T (65 million years ago). During each extinction, huge percentages of life were eliminated. However, that which was left (at times only 5%) rebounded, shaping today’s world after the first hominids appeared 4 million years ago.

For a more in-depth exploration of Earth’s History, please view our Prezi here.

Our bibliography is here.

Opinion Piece: Should They Suffer in Silence?

Is it our responsibility to help countries suffering from the effects of global warming?

In my opinion, it is the responsibility of not only this country, but all the world’s people, to help countries suffering from the effects of global warming. Those in the poorest countries, which have made the least contribution to climate change, have been and will continue to be the most impacted by the seemingly unstoppable terror that is global warming.

The main sources of stress caused by climate change are the rising sea waters and the pressure it places on the agricultural industry. Many small nations with a poor economy, such as the Philippines and Malaysia, are facing posed by the ocean when one lives mere feet above sea level. Additionally, the food supply is being thrown off-kilter by slowly increasing global temperatures and a lack of fertile soil--some of which is being swallowed by the seas.

If we trace global warming back to its roots, we find that the countries which shifted towards industrialization the earliest have contributed the most. For example, the US had its first Industrial Revolution in the mid 1800s, and since then has continued to be a main source of CO2 pollution. As the country now attempts to cut back on emissions and find a reliable, ‘clean’ energy source, other countries’ growth ( read: China) have overpowered our comparatively weak counterattacks. So now we say, “Well, this certainly must not be allowed to continue.” We turn to small countries like the Philippines: “Hello! You--yes, you. Don’t industrialize.” And they’re all like, “What? Oh no, that is not fair. You got us into this mess--what are you going to do to get us out??” And so, regardless of certain countries’ justified, but minor, outrage, aiding poor countries is an ethical issue.

Now, the issue that I have not addressed yet is this: How do we intend to fix this mess? We have our own problems! And yes, that is true. But: Can you honestly stand aside while innocent people, who struggle to get by on a daily basis, are forced out of their homes into a cold, unfeeling world? Can you tell me there is nothing we can do about this? And if these people do lose their homes, where will they go? They can move in with you--or they can be another drain on our tax dollars and honest income. I will only say this: There is always something you can do, something you can stretch, and, if you do lend a hand, you will find that it isn’t at all that hard.