The environment of our planet is seriously threatened by the garbage of the economy. What most urban population now breathes is closer to filth than to air. We all know pollution well; it is car-clogged streets, heavy smog conditions, junk- filled landscape, rivers and ponds stinking with industrial wastes.
The earth has its own waste-disposal system,but it has limits. The winds that ventilate the earth are only six miles high; toxic garbage can kill the tiny organisms that normally clean rivers. Meanwhile, modern technology is pressuring nature with dozens of thousands of synthetic substances,many of which almost totally resist decay.This includes aluminium cans that do not rust, inorganic plastics that may last for decades, floating oil that can change the thermal reflectivityof oceans, and radioactive wastes whose toxicity lingers for centuries.
The emission into the atmosphere of fossil fuel gases,also called 'greenhouse gases',such as carbon dioxide, nitrous oxide, Freon and methanelead to the global warming, which threatens to change the Earth's climate irreparably. The scientists predict that the rise in global temperature will produce new patterns of weather and extremes of drought, rainfall, hurricanes, tsunamis and earthquakes,seriously disruptingfood production in certain regions. Global warming will also cause the polar ice caps and mountain glaciersto melt rapidly, resulting in a rise in sea level and higher coastal watersflooding half of the Earth's population.
Another climatic effect of pollution is acid rain.The phenomenon occurs when fossil fuel gases combine with water vapour in the atmosphere. The resulting precipitationis damaging to water, forest and soil resources. Acid rain is blamed for the disappearance of fish in many rivers and lakes and for the widespread damaging of vegetation growth. It can corrode buildings and be hazardous to human health.
Scientists also fear that the ozone layer of the atmosphere is being depletedby the chemical action of Freons emitted from aerosol cans and refrigerators and by pollutantsfrom rockets and supersonic aircrafts. Depletionof the ozone layer, which absorbs ultraviolet radiationfrom the Sun, would have serious effect on living organisms on the Earth's surface, including skin cancer among humans.
Where do most of the pollutants end up? Eventually, in the oceans, which cover 70 per cent of the globe and have vast powers of self-purification.Yet even the oceans can absorb only so mush filth; scientists are worried about the effects on plankton- the microscopic animal and plant life drifting in the ocean and used as food by nearly all aquatic animals- which produce about one-fifth of the earth oxygen.
Ecologists, who study how living organisms and the non-living environment function together as ecosystem in thebiosphere, express their deep concern over the future of the planet. They claim that the biosphere - that extraordinarily thin global envelope which sustains the only known life in the universe - is under
serious threat. Trying to awaken a sense of urgency about the situation, ecologists do not hesitate to predict the end of the world.
Hundreds of millions years ago, plant life enriched the earth's atmosphere to a life-supporting mixture of oxygen, plus nitrogen, argon, carbon dioxide and water vapour. The mixture has been maintained ever since by plants, animals and bacteria, which use and return the gases at equal rates.The result is a closed ecosystem, a balanced cycle, in which nothing is wasted and everything counts. Today this balance has been broken: the output of carbon dioxide has reached a point such that.it may exceed both the capacity of plant life to remove it from the atmosphere and the rate at which it goes into solution in the oceans
A primitive community could harm only its own immediate environment. When it ran out of food, it had to move on or perish. But a modern community can destroy its land and still import food, thus possibly destroying ever more distant land without knowing or caring. Technological man forgets that his pressure upon nature may provoke revenge.
What most appalls ecologists is that technological man remains so ignorant of his impact. The men who designed the automobile did not foresee that its very success would pollute the air with car-exhaust fumes,turn cities into parking lots and destroy greenery in favour of highways, all over the world.
However, if technology got man in this environment crisis and pollution mess, can technology get him out of it again?
There is no lack of hopeful ideas for finding carbon-free sources for power, e.g. solar-power batteries and windmill turbines.Also encouraging today is the swell of public opinion.The natural balance can be restored if we develop collective will to achieve this goal. We have at least started to combat gross pollution.
Technological man is bewitched by the dangerous illusion that he can build yet bigger and bigger industrial society with scant regard forthe iron laws of nature. Pessimists argue that only a catastrophe can change that attitude - too late. By contrast, the hopeful environmentalists put their faith in man's common sense.
I. Agree or disagree with the statements given below. Use the following phrases:
That's right /Right you are. I don't think so.
Quite so/ Exactly. I'm afraid you are wrong here.
I entirely agree with you. I can't agree with you here.
I couldn 't agree with you more. Quite the contrary/Just the reverse %■
True enough. I see no point at all in claiming that...
My own view exactly. That's not the way I see it.
I'm of exactly the same opinion. I can't say that I share your view.
I'm with you there. I see things rather differently myself.
I can't help thinking the same. I am not at all sure, in fact.
I can see no reason to oppose.
I don 7 think anyone could/ would disagree with this.
1. What most urban population now breathes is very clean air and they have no idea about pollution.