Margaret D. Andrews
The utter magnitude of the ocean signifies that we live on a “water planet.” For just as the ocean envelopes 71 to 73 percent of the earth, our own bodies are 70 percent water. It is water that makes life possible.
If the earth was positioned farther away from the sun, all its water would freeze. If the planet was closer to the sun, the heat would vaporize the water. But the planet’s precise location allows the conditions for water, and life, to exist. Solar energy and gravity shift water from the oceans to the atmosphere, where it evaporates. (Water from lakes, rivers, soils, and plants is also carried upward.) The water in the atmosphere falls upon the land and ocean as fresh water. Finally, water on the land is returned to the ocean. This process, known as the hydrological cycle, is repeated continuously to distribute water and sustain life.
The immensity of the ocean can be deceiving. One glance from land’s end could lead us to believe that there is a plentiful supple of usable water on the planet. Although 97.1 percent of the world’s water is found in the ocean and in saline lakes, it cannot be used for agriculture or drinking. In fact, only .003 percent of the total amount of water on earth is considered fresh and usable. Glaciers, ice caps, the atmosphere, and deep soil hold another 2.9 percent of the earths fresh water in lakes, rivers, and some underground deposits. Yet 99 percent of these sources are eliminated by pollution, unavailability, and remote locations. Thus the amount from which the world’s people must draw is .003 percent.
It is also easy to misconstrue the distribution of life within the sea. Nearly all of it is concentrated along the coastal margins, or continental shelves. This zone represents less than 10 percent of the total area of the ocean, yet 90 percent of all marine life dwells there. Ninety percent of the world fish catch occurs within 200 miles of land. Tragically, it is in these critical habitats near the shelves, upon which we depend for food and recreation, that most of our polluting has taken place.
The size of the sea has historically been the justification for filling it with every kind of unwanted debris—from explosives and radioactive waste to sewage sludge and ammunition. The reasoning behind ocean dumping is that the ocean is so vast that it can never be saturated to the point where it will cease to function. During the industrialization of America, factories were planned near rivers for a source of power. The coasts became targets for factories too, because of shipping. The next step was that these waterways became the logical sites for dumping.
Today we know that 85 percent of all ocean pollution begins on the land. Whatever is flushed from the land will make its way, ultimately to the sea. How can our rivers, streams, and bays be clean if our soils are contaminated with pesticides, chemical lawn applications, and air pollution residues? If our pathways to the oceans are fouled, so is the ocean itself.
Nevertheless, the myth persists that any body of water as huge as the ocean must be able to recover from whatever is poured into it. But the poisonous quality and vast quantity of what we are dumping is beyond the ocean’s capacity for self cleaning.
Attitudes and Appreciations to Be Encouraged
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Without water, there could be no life as we know it, since water is the major constituent of cells and tissues.
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Clean water is not unlimited; hence, no person has the right to pollute or waste it.
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All the water used by a person or a community must eventually be used by others; so every user should be considerate of downstream neighbors and of future generations.
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As a burgeoning population demands increasing amounts of fresh water, people must look to the sea for extracting additional amounts.
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Some of nature’s most beautiful and awesome displays—rainbows, seascapes, waterfalls, clouds and thunderstorms—depend on water or on the energy released during the recycling of water.
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Evaporation from the sea and subsequent precipitation over land is the means of replenishment of fresh water for drinking, sanitation, recreation, and irrigation, and of falling water for hydroelectric power plants.
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Skills and Habits to be Developed
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Keeping streams, lakes, and oceans free of litter and pollution.
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Taking care not to waste tap water, even though the supply may seem limitless.
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Using to advantage the buoyant force of liquids to float objects or to decrease their weight.
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Remembering to give water to pets, household plants, farm animals, and even wild birds as they need it.
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Using correct terms such as fluid, displacement, buoyancy, vapor, condense, pollution, immerscible, sewage, and conservation.
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