Environmental Issues in the Ocean

Now that you have read about the origin of the oceans and what lives there, it's now important to look at the things that could jeopardize the balance of the marine biome as we know it. The major environmental threats to the ocean biome are over-harvesting of fish, and pollution of the water and atmosphere.

Over-fishing

Mankind has always looked to the sea for food. But how do you set restrictions on what is too much? Because of the lack of restrictions or laws concerning fishing, many marine species are becoming increasingly rare. A few laws have been proposed to reverse this problem, and some even passed, but no country is willing to spend the time or money to really confront this issue.

Industrialized fishing fleets now roam the seas, harvesting huge amounts of fish from the world's oceans. One fishing fleet, in four months, can produce 10,000 tons of fish products, 1000 tons of fish meal, 10,000,000 cans of fish and 100 tons of fish oil. Many non-food species such as dolphins and sharks are killed in fishing nets. There have been a number of ideas on ways to regulate fish harvesting, such a larger mesh in fishing nets so that younger fish that have not yet spawned may eacape. Many countries accepted this idea but, once again, were not willing to enforce it. An example that shows that this can be resolved is the treaties made against the harvesting of whales. The major fishing countries came together and made international treaties to prevent the near extinction of several whale species. This proves that glbal cooperation could solve the problems with the over-harvesting of fish.

Pollution

In our industrial world we generate wastes in large quantities; these wastes have to go somewhere, and often the oceans are used as dumping grounds for our discarded wastes. Ocean dumping of garbage was only outlawed about 20 years ago, and even until recently industrial and sewage wastes were discharged directly offshore. Oil tankers used to flush their tanks right into the ocean, but today contain the oily sludge for recycling. Spills are also a major problem. Off-shore oil rigs (at right) and oil tankers sometimes leak or are wrecked by storms, releasing huge amounts of oil into the ocean. Tanker spills like the Exxon Valdiz are examples of the great damage these kinds of spills can cause to the ocean ecosystem. New environmental regulations in many countries are trying to prevent such damage, and hopefully progress will be fast enough to save the oceans from being completely FUBARed.
Another pollution problem involves our "dumping" of carbon dioxide gas (CO2) into the atmosphere through the burning of fossil fuels. As shown at right, as this gas increases in the atmosphere it holds more solar energy in the atmosphere by absorbing infared radiation from the earth. Some scientists believe that this will result in global warming and lead to climate change on a world-wide scale. The oceans would heat up, changing currents and prevailing winds, and altering climates over land. The chemistry of seawater would also be affected, since CO2 is soluble in water and is involved in many chemical reactions. More frighteningly, global warming would melt the polar ice caps and result in "Water World"-- massive flooding of coastal areas currently heavily populated by people.

Scientists are studying these problems to try to find out their potential effects, and how to control their impacts on the oceans and on us. But it is clear that we must take care of our oceans, or the consequences could be disasterous . . . .

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