Oceanography
Oceanography is the scientific study of the oceans, which cover over 70 percent of the Earth's surface. Earth's water supply, 98 percent of which is ocean water, makes it unique compared to the other eight planets in our solar system, which do not have appreciable amounts of water. The oceans directly and indirectly affect all life on Earth: its origins, its ecosystems, and its access to a variety of resources.
Oceanography is divided into four major areas of research: physical, chemical, biological and geological. The physical aspect of oceanography includes studying many basic processes such as the currents, tides, development and maintenance of boundary layers, rates of water transport, etc. Chemical oceanographers study the chemical constituents of the sea, and the availability of chemical elements such as zinc, copper and nitrogen in the water. Biological oceanography involves the study of all aspects of life in the sea including rates of primary and secondary productivity, reproduction, predation, influence of seawater chemistry on organisms, as well as other types of ecosystem dynamics. Geological oceanographers are concerned with the geological structure and mineral content of the seafloor, especially with respect to mineral resource extraction, seafloor mapping, and plate tectonics. Man's curiosity about the sea is constantly matched with opportunities to further knowledge in countless areas.
Early exploration of the oceans with rafts and small boats offered humans a chance to see new places and encounter new cultures. This led to the exchange of goods and information. Although most exploration during the 1400s to 1800s was driven by commericial interests, some ships' captains or other officers, in addition to constructing maps, collected and recorded observations about the oceans' winds and current systems. The HMS Challenger, perhaps the most famous ocean research vessel, marked the advent of modern oceanography with its unprecedented forty month long, oceanographic voyage in 1872.
Matthew Fontaine Maury (1806-1873) is often called the "father of oceanography". His early achievements centered around studies of ocean currents and winds with respect to navigation. An unfortunate accident in 1839 left him permanently disabled and forced him to retire from active duty in the American Navy. However, this mishap did not deter his research activities in physical oceanography. In 1855 he published the first textbook of modern oceanography called The Physical Geography of the Sea.
Ocean exploration is now conducted by specialized vessels designed to help further oceanographic research. These ships use sophisticated tools developed to test and precisely measure oceanic conditions in the deepest areas of the seas. Sophisticated sonar and magnetic technology deployed on research vessels have greatly increased scientists' knowledge of the oceans, making possible such important geological discoveries as seafloor spreading and plate tectonics. All ocean research ships are essentially floating laboratories operated and financed by organizations such as the United States Navy, universities, and marine research institutions. Typical research equipment includes a magnetometer, an echo sounder, and devices for sampling marine life and the seafloor.
Early in the 20th-century three major oceanographic institutions opened in the United States. Today these are known as Scripps Institution of Oceanography in San Diego, Woods Hole Oceanographic Institution in Woods Hole, Massachusetts, and Lamont-Doherty Earth Observatory in Palisades, New York. Some of the largest-scale oceanographic research performed anywhere has been carried out through the leadership of these institutions working with a variety of other organizations. Perhaps the most important of these are the deep sea drilling programs. These began in 1968 and are still going on today. They include the Deep Sea Drilling Project and the Ocean Drilling Program both of which concentrated primarily on recovering long sediment cores from the ocean bottom for geological research. Another very important long-term project is the Geochemical Oceans Sections program, which began in 1972 and involves analyzing water samples from throughout the ocean in order to study circulation patterns, climate change, mixing processes, etc.These types of research activities have significantly contributed to understanding of the oceans in all areas of marine science.
Modern technology has certainly made exploration and research of the oceans much easier. However, the tremendous pressures involved in deep sea exploration still represent a significant limitation to first-hand observations in deep ocean environments. Although manned research submarines now can rountinely penetrate to depths of more than 3.75 mi (6 km), the cost is rather prohibitive. Two solutions to this problem are Remotely Operated Vehicles (ROV's) and Autonomous Underwater Vehicles (AUV's). ROV's are unmanned submarines that are tethered to a support ship that guides them by remote control. AUV's, although also unmanned, do not require a support ship on site. They are essentially submarine robots capable of exploring tremendous areas of the deep seafloor with less risk and less cost. Although in the late 1990s they are still in the experimental stages, perhaps they represent the future of deep ocean research.
This is the complete article, containing 790 words
(approx. 3 pages at 300 words per page).
