Otázka: The environment, nature and weather
Man is changing the world’s environment. It was in the past, it is nowadays and I think that it will be also in the future.
Early man lived by gathering wild foods and by hunting and fishing. Then he became a farmer, reared domestic animals, learned to store food and began to burn forests to obtain more land for agriculture and cattle grazing. Then he started to build towns and cities, and dams and canals for irrigation. Great civilizations grew up in the major river valleys and their populations multiplied. But large areas of land lost their productivity through overdevelopment and the great civilizations disappeared.
2) Problems of environment:
As countries develop, they use more and more energy. In the last three hundred years new sources of energy like coal, natural gas and petroleum have made the colonization and exploitation of new lands quicker but without environmental controls and because of it there exist many problems like:
All life on our small blue planet depends on a thin layer of gases, called the atmosphere. Like a transparent blanket, the atmosphere keeps the surface of the Earth warm. Without it the average temperature on Earth would be around minus 18°C. With this atmospheric blanket the average temperature is actually around plus 14 degrees Celsius. The energy from the Sun, in the form of ultraviolet radiation, streams in through the atmosphere and warms the surface of the Earth. In a similar way, the energy is reflected back out into space as infrared radiation, and absorbed by gases such as carbon dioxide. This process is called the greenhouse effect which has become one of the world’s most discussed topics because it causes global warming. Man himself is the greatest contributor of the greenhouse effect. He has polluted the atmosphere with dangerous gases such as carbon dioxide from fossil fuels (coal, oil, gas etc.) and CVC which are found in refrigerators and aerosol sprays. Global warming could also cause rising sea levels, unpredictable weather in the form of flooding or drought, hurricanes and it could destroy many tropical rain forests which are so important for the Earth’s climate. The solution of this problem is simply to produce less carbon dioxide. We can do it in many ways: hang out the washing instead of tumble drying, switch off lights when not required, share our car journeys with someone else and plan how often we use the car, fill the kettle with only as much water as we need and many others.
It was discovered that the ozone shield is thinning at a rapid speed, over the Antarctic it was even missing. But earth’s ozone layer, a protective layer of gas high in the earth’s atmosphere, is breaking down also over other populated places on the Earth. As it does, it is allowing more and more of the sun’s invisible harmful rays to reach Earth’s surface. These rays of the sun are called ultraviolet, or UV rays. UV rays are known to damage the life on the Earth because they bring about diseases like cataracts (sometimes even blindness), skin cancer, they break down the immune system and they can disrupt the process of photosynthesis, which is necessary for plant growth. Most scientists agree that the greatest damage to the ozone layer has been caused by chemicals released into the atmosphere by people. These chemicals are again used in refrigerators, air conditioners and some kinds of cleaning fluids but most of the damage has come from factories. We should keep in mind that ozone destroying chemicals stay in the atmosphere for as long as 100 years. The only solution of this problem is to ban the use of dangerous chemicals in aerosols, refrigerators and car air conditioning.
One of Europe and North America’s most serious pollution problem is acid rain. What happens? First, power stations (by coal burning) and factories send gases and chemicals into the air. There they mix and are carried for hundreds kilometres by the wind. Finally they fall back to the earth when it rains. This acid rain kills fish and trees. It slowly destroys concrete buildings and bridges, too. Removing the sulphur dioxide from chimneys of power stations and using alternative sources of energy can solve this problem.
We produce lots of waste in the home and toxic chemicals from industrial processes. These must be disposed of safely. It is less expensive to dump waste and toxic chemicals into rivers or holes in the ground than to dispose of them safely. Toxic waste kills fish in rivers, lakes and the sea. Wastes getting into our drinking water or chemicals getting into our food cause illness and diseases.If laws and regulations are followed by all countries, the environment will be cleaner.
Before 1900, rainforests covered 14% of the world’s surface. Today they cover only 7%. The reason for this is simple. They have been cut down to provide land, paper, wood, medicines, minerals and fuel. But it’s not only trees which are disappearing. Every rain forest also contains millions of animals, insects and flowers. These are destroyed, too. If man continues to cut down rain forests, more than one million species of plants and animals will become extinct by the year 2030. Governments should protect certain areas and plant new forests. The forests absorb carbon dioxide in the process called photosynthesis. Without trees carbon dioxide levels will increase.I think that we can solve this problem of cutting down the rainforest by discovering alternative sources for food and wood.
At the moment, 94% of the world’s energy comes from fossil fuels. There’s enough coal for the next 300 years but only enough gas and oil for the next 50. What happens then? Well, one answer is nuclear energy. But after the Chernobyl disaster in 1986, many people think nuclear power isn’t safe. There are four “Green” solutions. They all use natural energy already in the environment and it is: wind energy, solar energy, tidal energy (from the sea) and geothermal energy.
THE SEASONS OF THE YEAR:
There are four seasons of the year – spring, summer, autumn and winter. Spring officially begins on March 21st. In spring there is a lot of rain and sunshine. The days slowly get longer and warmer so that plants begin to grow again. In summer, which begins June 21st, the days are usually hot and sunny but there can also be a lot of rain. Autumn, which begins on September 23rd, is probably best known as the season when the leaves on the trees change to bright colours. Autumn is also known for its windy weather. The days get shorter and colder as winter approaches. The season which begins December 22nd is winter. In winter the weather is cold and there is a lot of snow. I think living in a country where there are four distinct seasons is much more interesting than living someplace where the weather doesn’t change much.
THE WEATHER IN THE CZECH REPUBLIC:
The Czech Republic has a continental climate which means the weather changes a lot during the year. There are four distinct seasons – in spring it is warm but with many cool, rainy days, in summer it can be very hot but it also rains quite a bit, in autumn the days are cool with foggy mornings, and in winter it gets quite cold and it can be windy and snowy. The highest temperatures occur in July and August when the temperature can go up to 35 degrees centigrade, but usually it only gets up to 25 or 30 degrees. January is usually the coldest month of the year with normal temperatures of around freezing to about 5 degrees. On extreme days the temperature can go down to 20 degrees below freezing. If you average the temperatures over the whole year, the Czech Republic has an average temperature of 9.8 degrees centigrade.
Some of the natural disasters are for example earthquakes (especially Japan, USA), tidal waves
(Asia – they are connected to earthquakes in the ocean), gales, hurricanes and tornadoes (USA), volcano eruptions (Italy, Greek), avalanches in the mountains, extreme heat (Australia), drought in Africa which causes famine.
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