Онлайн-урок №9 "Environment. People and nature. Passive voice."

  Our planet Earth is only a tiny part of the universe, but nowadays it's the only place where we can live. People have lived on our planet for many years. They lived and live on different continents, in different countries. People depend on their planet, the sun, animals and plants around them. Environment is everything in the world around us that surrounds and affects all life on earth, including the air, food, water, plants, animals and so on.
  Environment is the place where we live. Since ancient time nature has served people, being the source of their life. For thousands of years people lived in harmony with environment and it seemed to them that natural riches were unlimited. But human interference in nature began to increase with the development of civilization. Our ecology becomes worse and worse with every new day. Many species of animals and birds are disappearing nowadays. People destruct wildlife, cut down trees to make furniture. They forget that people can’t live without trees and plants, because they fill air with oxygen.
  There are a lot of ecological problems. The most serious ecological problems are: noise from cars and buses, destruction of wildlife and countryside beauty, shortage of natural resources, the growth of population, pollution in its many forms. Water is everywhere, but there is no ocean or sea which is not used as a dump. Many rivers and lakes are poisoned too. Fish and reptiles can’t live in them. People can't drink this water. So we have to clean the water environment.
  Another problem is air pollution. Air pollution influences the health of people. For example, ultraviolet radiation from the sun can cause skin cancer. Normally the ozone layer in the atmosphere protects us from such radiation, but if there are holes in the ozone layer, ultraviolet radiation can get to the earth. Many scientists think that these holes are the result of air pollution. Also, we have problem with nuclear pollution. Nuclear pollution cannot be seen but its effect can be terrible. To make air clear we need good filters at nuclear power stations, at factories, in cars and buses.
  One more problem is growth of population. They don't have enough places to live. They need more water, more food. So it is the reason of the shortage of the natural resources. It is very difficult to solve this problem. Also one of the most serious problems is greenhouse effect. It works like this: sunlight gives us heat. Some of the heat warms the atmosphere and some of the heat goes back into space. Nowadays the heat can't go into space. That's why winter and summer temperatures in many places have become higher. If the temperature continues growing up, the snow on the mountains and ice will melt, so most of the earth will be under water. So every person has to understand how important it is to solve these problems, which endanger people's life.

 During the day, we see a bright sphere called the Sun move across the sky. Its path is fairly regular from day to day, but changes gradually during the 365-day seasonal cycle. Why doesn't the Sun always rise in the same place each day? Where does it go at night? How does its light cast shadows on our world?
  We experience the alternation of daylight (day) and darkness (night). Clocks show us that the total time needed to complete one day and one night is always 24 hours, but the proportion of each varies for different 24-hour periods. Also, we can see that the Earth is never completely light or dark at one time. How can it be noon in Boston, 5 PM in London, and 9 AM in San Francisco at the same time? Who has the right time?
  Much of the Earth's population experiences a repeating pattern of temperature and weather changes over a 365-day period. Weather goes from generally cool days (spring) to hot days (summer) to cool again (fall) and then to cold (winter) and back to cool. These seasonal changes affect animal and plant life dramatically. They are of varying duration and varying character at different locations on the Earth. How can we have summer in the USA and winter in Australia at the same time if they both turn toward the Sun once a day?
  Mankind has wondered about these and other aspects of our ordinary experience for millennia. For generations, people just like us have observed and pondered and guessed about the world we live in. They have constructed "models" to explain the phenomena around us and have refined and changed and discarded these explanations based on further observations and reflections. Much of our current understanding is built upon the inspiration of observers and inquirers going back before Plato. We owe much to the inspired works of Copernicus, Kepler, and Newton.
  Today we know that the Earth is a mostly solid sphere that turns on its axis once every 24 hours. The Earth revolves around the Sun, a very large and very hot sphere of gas situated millions of miles away from us. One such revolution takes approximately 365 days. The Earth is tilted on its axis of rotation with respect to the Sun, and this tilt, coupled with the Earth's movement around the Sun, causes the alternation of our seasons. The Moon, in turn, is a smaller solid sphere that revolves around the Earth about every 28 days. It reflects the light of the Sun and shows us its "phases", depending upon the relative position of the Sun, Earth, and Moon.
  Although these and other modern scientific explanations can become complicated and even can run counter to our intuition, they really are rooted in the everyday experience of people who wondered about the world around them. This is the essence of science: to be explorers of our own world, to engage ourselves in the Spirit of Inquiry by observing what is around us, asking questions and looking for answers that are consistent with our experience. And although we cannot hope to reconstruct all scientific understanding from first principles, each one of us can be a scientist with regard to our own experience. We can observe the world and wonder about it and see how our observations and deductions mesh with scientific knowledge.