Oceanography


Oceanography, also called marine or oceanology, is the study of oceans. It covers the topics of marine organisms, ecosystem dynamics, ocean currents, waves, geophysical fluid dynamics. It also includes plate tectonics, the geography of the sea floor, fluxes of various chemical substances, and physical properties within the ocean and across its boundaries.
Four branches of oceanography are biological oceanography, chemical oceanography, geological oceanography, and physical oceanography.
  • Biological oceanography is the study of plants, animals, and microbes of the oceans and their interaction with the ocean.
  • Chemical oceanography is the study of of the chemistry of the ocean and its chemical interaction with the atmosphere.
  • Geological oceanography is the study of the geology of the ocean floor and the plate tectonics.
  • Physical oceanography is the study of the oceans physical attributes. This includes sound, light, and radio waves in the ocean, temperature/salinity structure, currents, mixing, internal tides, internal waves, and surface tides.


History of Oceanography


Humans first started studying oceanography in prehistoric times. Observations on tides are recorded by Aristotle and Strabo. Early exploration of the oceans was primarily used for cartography. Juan Ponce de Leon first discovered the Gulf Stream in 1513. However, the first scientific study of the Gulf stream was made by Benjamin Franklin. Franklin measured the temperatures of the water in many different Atlantic crossings. He also explained the cause of the Gulf Stream correctly. The first printed map of this body of water was made in 1769-1970, by Benjamin Franklin and Timothy Folger.
During the year 1871, an expedition to explore the world's oceans was sponsored by the British government. Scots Charles Wyville Thompson and Sir John Murray, during 1872-1876, launched the Challenger expedition. Biological, physical, and geographical aspects were covered in 50 published volumes of the results of this expedition. There were four thousand seventeen new species that were discovered. Many other places set out on expeditions to further explore the oceans. All of these expeditions led to the book The Depths of the Ocean, published in 1912.


Connections to the Atmosphere


Global warming and related biosphere concerns are linked to the study of oceans. Each are influenced by each other and the same dynamics occur in both. The sea may be a thousand times denser than the atmosphere, but they are still connected.
All water and the atmosphere have a certain cycle. This cycle is called the Hydrological Cycle. The Hydrological Cycle happens all over the world.
The order of the Hydrological Cycle is followed:
  • First, participation will occur
  • Second, there is infiltration and groundwater moves
  • Next, water will either evaporate, or be move into plants to form transpiration
  • Then, the water that has gone through transpiration or evaporated will turn into condensation
  • Last, it will begin to precipitate again, and the whole process will start over

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Oceanography Facts


The ocean covers about seventy one percent, or three hundred twenty-eight million cubic miles, of Earth's surface. It contains almost ninety seven percent of Earth's water. The temperature of almost all ocean water is about thirty-nine degrees Fahrenheit , only a few degrees warmer than freezer temperature. About ninety percent of the world's volcanic activity occurs in oceans. The average depth of the ocean is about twelve thousand two hundred feet, more than two point five miles. The deepest point of the ocean is thirty-six thousand one hundred ninety-eight feet, which is in the Mariana Trench, part of the western Pacific. The world's oceans contain more than twenty million tons of gold. A swallow of sea water contain millions of bacterial cells, hundreds of thousand phytoplankton, and tens of thousands of zoo-plankton.
Each and every day, a couple hundred earthquakes occur on Earth. However, most of them occur in the ocean. Also, a big majority of volcanic activity happens in the oceans along with earthquakes. The greatest number of volcanoes occur on the ocean floor. Underwater volcanic eruptions occur in specific places, not randomly. An earthquake in the ocean can only occur in certain places, too. These earthquakes cause tsunamis.


Ocean Salinity


Salinity is the amount of salt in an area. It depends on two important factors; the amount of evaporation taking place and the amount of freshwater being added. As ocean water evaporates, it leaves the salt behind causing the water left to be more salty. Ocean salinity can vary from place to place. When there is high evaporation, there is higher salinity. When there is high freshwater input, the salinity is lower. Salinity can also vary with depth. The average salinity of ocean water is about thirty-five grams. It is rarely ever below thirty-three grams or above thirty-eight grams. The two bodies of water with the highest salinity is the Red Sea and the Persian Gulf, which is forty grams, due to the high evaporation rate and low freshwater input. The two bodies of water with the lowest salinity is the Baltic Sea, with five to fifteen grams, and the Puget Sound area, with twenty-one to twenty-seven grams of salt.
One kilogram of water contains about thirty-five grams of salt. In other words, a two litter bottle of ocean water contains five tablespoons of salt. If every ocean dried up, it would leave a twelve story high pile of salt.The saltiest ocean is the Atlantic Ocean, and the least saltiest are the polar waters. Salinity is a high risk factor for both plants and animals in the oceans.

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Random Facts

1. Ninety-four percent of life on Earth is made of water.
2. Most of our planet is in a perpetual state of darkness, due to the fact that light can't penetrate more than three hundred thirty feet under Earth's surface.
3. About half of the Earth lies beneath water.
4. There are more artifacts and remnants in Earth's waters than all of the museums in the world combined.
5. Ocean explorers have only studies less than five percent of Earth's oceans. Scientists know more about Mars than they do about the ocean floor.
6. The Mid-Ocean Ridge has higher peaks than the Alps and takes up twenty-three percent of Earth's surface.
7. Scientists didn't start to study the Mid-Ocean Ridge until 1973.
8. The ocean has many pillars that reach up to several stories high and chimneys that shoot up sulfuric acid.
9. Beneath the ocean's surface, there are upside-down lakes, underwater lakes, and sometimes even waterfalls, by popular vacation beaches.
10. There are one hundred forty to six hundred foot long jellies living on hydrothermal vents that use the process of chemosynthesis (which is similar to photosynthesis.)
11. At depths that can easily crush the Titanic, crabs, tube-worms, and octopuses go about their business, amazingly unharmed.


References

http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/education_oceanographic_facts.html
http://www.iwr.msu.edu/edmodule/water/cycle.htm
http://ww2010.atmos.uiuc.edu/%28Gh%29/guides/mtr/hyd/home.rxml
http://www.savethesea.org/STS%20ocean_facts.htm
http://www.buzzle.com/articles/oceanography-facts.html
http://www.abc.net.au/water/stories/s1572428.htm
http://darkwing.uoregon.edu/~drt/Oceanography/Lectures/08/salinity/ocean_salinity.html
http://oceanservice.noaa.gov/facts/volcanoes.html
http://openlearn.open.ac.uk/mod/resource/view.php?id=171651
http://www.motherearthnews.com/Nature-Community/Fun-Surprising-Facts-About-The-Oceans.aspx