The Ocean / Океан
The world’s ocean covers about 70% of the Earth’s surface. It is use to produce us many things. It is more than a place to swimming, sailing and other recreation. The ocean serves as a source of energy, raw materials and most of all food like fish and seaweed. In this essay I will talk about «What are our ocean resources and the importance of the oceans in the future.»
First, our largest resource in the ocean is food. There are two different kinds of food in the ocean, such as marine plants and marine animals. These two kinds of resources are reborn resources and it will never be end. For marine plants we have the algae’s family, like seaweed. During ebb tide, you can find the seaweed between rocks. For the marine animals we have fish and shrimp. The fish and shrimp are always moving around the ocean and follow the ocean currents.
What is ocean current? It is a movement of ocean thatcan buring the fish to other places. There are two kinds of circulation create the currents in the ocean. They are wind-driven circulation and Thermohaline circulation. Wind-driven circulation result from the wind sets the surface waters into motion as currents. The currents generally flow horizontally-that is parallel to the earth’s surface. The wind mainly affects only the upper 100 to 200 meters of water. However, the flow of wind-driven currents may extend to depths of 1,000 meters or more.
Thermohaline circulation produces great vertical currents’ hat flow from the surface to the ocean bottom and back. The currents largely result from differences in water temperature and salinity. The currents move sluggishly from the polar regions, along the sea floor, and back to the surface. In the polar regions, The surface waters become colder and saltier. Being colder and saltier makes these waters heavier, and they gradually flow back toward the surface and replace the surface waters that sink. For example, as a warm ocean current and a cold ocean current meet together, The warm water will always follow cold water and moving around the ocean. The most important is the plankton does not like to stay in the cold place. They will follow the warm current. As the result the small fish like shrimp that eats plankton, will follow the plankton. Similarly the bigger fish that eats small fish and shrimp will just follow also and these fishes became a chain.
Our ocean has produced raw material also. Like natural gas and petroleum. These materials are all unaltered. After you have take them out, you need to use machine to take out the dirt. For example the petroleum is use to sucked out by the big pipes. The asphalt road and the clean oil can be the fuel. South china sea has a big processing plant that produces the oil and natural gas. In late 1980′s, offshore wells produced about 25 percent of the world’s oil and about 20 per cent of the world’s gas. Scientists estimate that 3 trillion barrels of oil lie undiscovered beneath the ocean. Equally huge amounts of untapped gas accompany the oil. As gas and oil reserves on land are use up or become too difficult and expensive to obtain, finding and recovering undersea deposits will become increasingly important.
The ocean can be use to produce power. First, we have wave power. Generator was built in the ocean. It has a pumping chamber. It will move up and down to turn the generator. Second, we have tidal power. The generator will have to build on the place were water will falls. The best place is to built it on a dam. Once the dam is full, the water will rush down and it will turn the generator to produce the energy.
Our ocean is very useful, but we are the one that endangers it with pollution. The most common pollution is trash and the chemical waste. People go to sea to fish or to swim they always leave trashes like cans and plastic bag. These things are not easy to dissolve and if we put them together, oh my god can you image? That will be like a small mountain every day.
The next common pollution is the chemical waste (sewage). This pollution is always coming from factories, household and human. That can poison the environment and also contains bacteria, viruses and parasite eggs. That is harmful to human health. The bacteria can give swimmers’ stomach upsets or infections. It is liquid and easy to dispersed through out the water and marines lie than it is hard to wash it out anymore. The north sea is one of the most polluted seas in the world. Rivers from the industrial countries of western and central Europe will flow into the southern part of the north sea. The sewage can dissolve by small bacteria’s but needs long time. In many places, sewageses are left before it is disposed. It can be treated to make it safer but this is expensive.
The next pollution is the spill out oil. I think most of people have heard about it. But where is it come from? Now is our ocean there were many tankers are sending oil to other countries or to their own country. Sometimes the tanker might hit the ice or mountain under the sea. And then the oil will come out from the hole. Oil is very dangerous to the environment, especially marine animal and sea birds. Once the oil is on marine animals’ body, their body will have hard time to breathe and then they will die. For example, whales are using lung to breathe. They need to float over the water to breathe, so they need to float over water to breathe every period. If they suck in the oil they will be sick and die. Also the birds, if the oil is on their body they cannot keep warmness and they will die because of cold or they will swallow it in when they try to clean it with their mouth.
On March 24 1989. The oil tanker exxan valdez van aground in Prince William Sound in Alaska. It spilled over 11 million gallons of crude oil. The effect on the land environment was killed in huge numbers. Offers are poisoned by oil, Ether by swallowing it as they swim through it or by trying to lick it off their coats. However, the main cause of death is exposure too cold. If oil clogs otters fur they freeze to death, then few of these sea attars have cleaned. But about 3,000 along with 36,000 seabirds and over 100 eagles are estimated to have died.
Change salt water to clean water is very easy. The scientists invent a machine which can change the salt water to clean water. First, you have to boil the salt water and wait until the salt water become steam then the salt will be left in the container and wait or the steam become clean water.
Water is the most critical natural resources in the year 2,000. According to «Thors, orig. Water spells lie itself. It’s used in agriculture, domestic taps and industry. Not only in food production, drinking and business. If we don’t protect it well, in the future it is hard to change the salt water to clean water, then we will not have clean water to drink, to plant and to agriculture.
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