Boundless as the vast oceans are, incredibly formidable it is to people in the hours of inclement violence. And it seems then that no force can handle a mighty abyss. Alas! This impression is deceptive. Serious danger threatens the ocean: the ocean, drop by drop, flew alien to the ocean environment substances that poison water, destroy living organisms.
So what is the danger of the ocean?
It is pollution, i.e., the introduction of a substance or energy into the marine environment by humans that harms marine organisms, threatens human health, makes seawater unusable, and, of course, destroys the beauty of seascapes. Pollution can be mechanical, thermal, energy, chemical. Anyone who has ever been to the seashore is familiar with mechanical pollution. The waves carry a variety of objects to the beaches, abandoned or pulled down from the decks of ships, scraps of fishing nets, items of the navigational environment, etc..
Sometimes (for example, along busy shipping lanes) thrown garbage borders the coast with multi-meter ramparts. Heat pollution significantly increases the natural water temperature level.
Under maritime conditions, thermal pollution can only be local. It is caused by the discharge of heated wastewater in areas of large cities, runoff from nuclear power plants (such as on the east coast of the United States), and others. In extreme cases, the water temperature can rise by several degrees in a short period of time. In this case, the natural balance in the contaminated area is disturbed, cold-loving organisms die, their place is taken by flora and fauna alien to this water area. Especially destructive is thermal pollution for bottom organisms.
Energy pollution of the marine environment is also manifested, only locally. It occurs during certain types of geophysical works, during which artificial electric or magnetic fields are created, and energy is released into the environment. For example, when offshore electrical exploration is conducted, electrocution of fish may occur, and seismic exploration may cause damage by elastic oscillations.
At present, areas of lesions of marine organisms in various types of work are experimentally established, and precautionary measures are determined, particularly thanks to speeches by politicians.
Chemical pollution is most dangerous to the ocean environment and its inhabitants. Annually, up to 25 billion tons of carbon dioxide, about 190 million tons of carbon monoxide, about 110 million tons of sulfur dioxide, about 70 million tons of nitrogen oxides, more than 50 million tons of hydrocarbons, etc. are delivered to the atmosphere from technological sources. Much of this mass of pollutants fall together with atmospheric fallouts on the surface of the oceans.
The value of the annual flow of dry salts from the atmosphere to the ocean surface is 900 million tons, which gives an average value of 2.6 g per square meter of the ocean surface. Only different hydrocarbon compounds in the sea basins of the Northern Hemisphere fall out annually about 2.1 million tons, the Southern Hemisphere – about 1.2 million tons.
Geologists estimate that about 28.5 billion tons of various substances fall into the world oceans annually. The bulk of them is suspended together with river discharge – 18 billion tons. Another 4 billion tonnes of substances are carried out by rivers in dissolved form. Household waste (excluding organic fuel) “enriches” the ocean environment by 3 billion tons. The same amount of substance is given to the ocean by glaciers. The rest comes from rock particles, volcanic dust, solids, which are emitted into the atmosphere by industrial plants.
Of course, not all of this mass is considered to be a pollutant, but on a planetary scale with river waters more than 320 million tons of iron compounds, 2.3 million tons of lead and 14 million tons of phosphorus are discharged into the sea annually. As a result of discharging untreated wastewater into rivers, the amount of mercury discharged from land increases twofold annually, and lead, copper, and zinc – 12-13 times.