Oceanography is the study of the sea and oceans. It is composed of the geological study of the ocean floor and ocean features. The geological aspects of the oceanography include physical oceanography which is concerns with the physical attributes of the ocean water for example currents and temperatures and the chemical oceanography whose main focus is on the chemistry of ocean waters. Marine biology is the study of the oceanic flora and fauna. Oceanography also studies the meteorology which is the interaction between the atmosphere and the ocean.
The Indian Ocean, Atlantic Ocean, the Pacific Ocean, Arctic and Antarctic oceans and the Mediterranean Sea among others are integrated in oceanography. Naturalists as Thompson, a Scot, and John Murray a Canadian were among the first pioneers to discover and study oceanography. (Johnson 2005). The paper examines some of the physical, chemical and the marine features present in the oceans. Oceanographic Properties Physical oceanography refers to the discovery and the study of physics and the geography of the ocean currents and water properties.
The major components are the dynamics of ocean currents on scales from centimeters to global, the ocean wave phenomena the distribution of heat and salt and their transport through the ocean basins, the exchange of the momentum, heat and freshwater between the ocean and the atmosphere, the interaction between the ocean and rivers, estuaries, ice and marginal seas. Physical geography has important application in global climate, oceanic mixing and coastal studies and in the studies of primary production, hydrothermal vents and oceanic flux and storage of carbon dioxide (Robert 2005).
The ocean is composed of a mixture of 97% pure water and 3% other materials examples as salts, gases, organic substances, and the undisolved particles. Pure water determines the physical properties. The ocean is measureless covering 71% of the earth surface of which 65 % is considered open ocean- waters that lie far away from the costal ocean. Oceans are different with an averaging depth of more than two miles and containing vast life all over it even in the deepest bottoms.
Oceanic life is composed of two major categories; the pelagic (ocean water) and the benthic (the sea floor). Pelagic is further divided with accordance of water depth. Fig 1. 0 parts of the ocean The first 200 meters of the ocean water is called the neritic zone which includes the seashore and offers abundant food for the larger animals due to the plentiful of small organisms. The ocean zone extends from 200 meters deep to the bottom of the ocean. Often the ocean zones are classified according to the amount of sunlight they receive.
The top part which photosynthetic life is found called euphotic zone while the preceding zone is the dysphotic zone where light is too dim to support photosynthesis. The aphotic zone where there isn’t any light rays. Littoral zone is closest to the seashore covering a distance of 600 feet from the shoreline and is divided into three zones namely; the supralittoral which is submerged due to unusual high tides or during storm. The intertidal zone lies between the high and low tide lines then the sub-littoral which extends from low tide up to 200 meters.
Ocean water salinity refers to the amount of salt found in the 1,000 grams of water. Majority of the salt content in the ocean comes from land but some originates from the undersea volcanoes thus the average ocean salinity is 35 grams of salt per 1,000 milligrams. An estuary refers to the point where fresh river water meets the oceans salty waters. Its salinity is different from the salinity of the ocean adjacent to it Most estuaries are found at river mouths and are thus long and narrow, resembling a channel.
The water pressure increases with the increase in depth while the temperature which is the measure of hotness or coldness of an object is divided into three temperature vertical zones. ? Top layer is the surface or mixed layer and it’s greatly influenced by the solar system. ? The following layer is the thermocline and the temperature drops with the increase in depth, ? Then the third layer is deep-water layer and at this point the temperature decreases slowly with an increase in depth. In the ocean, the water density depends on the temperature, pressure and its salinity.
For instance cold salty water is denser than fresh and warm water. The density further subdivides the ocean into three layers namely, the surface mixed where the temperature and saline content differs hence no great effect on density since it’s in direct contact with the air. Next layer is the transition zone where water remains cold and dense and it’s the barrier between the surface and the bottom zone allowing little water movement between the two zones. The bottom zone is where water remains cold and dense.
This has been illustrated by the figure 2. 0 below. Fig. 2. 0 Density layers in the ocean Ocean currents The current keeps the ocean in a constant motion and moves large amounts of water into great distances. It is driven by wind forces, gravitational forces and tidal movement. There exists different types of current namely the Antarctic Circumpolar Current, Eats wind drift, the North and Southern equatorial currents, the Peru currents, the Kureshio current and last the Gulf Stream. They flow in gyres which are loops of water.
The gyres spin in a clockwise direction and in the southern hemisphere they do spin in anti-clockwise direction. The currents can be illustrated in the Figure 3. 0. The United States of America normally experiences the effects of the Gulf Stream currents in the Northern Atlantic zone, the equatorial current and the Canary current. Mostly affected coastlines are the Florida’s East coast, North Carolina and the Newfoundland. Figure 3. 0 oceanic currents Marine Biology By looking at the ocean surface, it is difficult for one to see the great diversity of life that exists in the ocean.
The ocean inhibits different kinds of flora and fauna. They include the mammals, which are animals with backbones hence they are vertebrates. They unique features is that they breath air lungs, give birth to young ones, produce milk, are warm blooded and are covered with fur. They are the seals, sea lions, walruses, the sea oter and the polar bear. Other oceanic creatures include the giant squid, angelfish coelacanth, lantern fish, gulpers whales, sharks, fishes of all kinds. Other forms of ocean features are the coral reefs.
(Cone 1992) Oceanic coasts There are various types of coasts in the ocean and the beaches are only but one type. They are divided into two categories namely the primary coasts and the secondary coasts. The primary coasts were created by non-marine processes. They happen because of changes in the land, such as river deltas or lava flows while the secondary coasts were formed by marine action and are caused by changes in the ocean, such as the creation of barrier islands or coral reefs. Reference
Information on the “Focus on the Ocean” www. onr. navy Retrieved on 28th March 2009 Cone J. , (1992). “Fire under the Sea”, NY: Sage Robert H. S. (2005), “Introduction to physical oceanography” Texas: A&M Information on “The introduction to physical Oceanography” www. es. flinders Retrieved on 28th March 2009: Australia: Flinders university Press. Johnson D. (2005) “Information that relates to the Ocean World” www. oceanworld. tamu www. whoi. edu Information on “The Marine Biology” www. springerlink. com Retrieved on 29th march 2009.