Environment

outline: –    what I am going to talk about

• foreword
• human population
• global warming
• the ozone layer
• what I do

The problems facing the environment are vast and diverse. Global warming, the depletion (ztráta,ochuzení) of the ozone layer in the atmosphere, the cutting down the rain forests, air pollution, acid rains, water pollution. are some problems, which can reach critical proportions in the coming decades. All of these problems are directly affected by the size of the human population.

Human population

Human population growth is at the root of all the world’s environmental problems. Although the growth rate of the world’s population has slowed, the population still grows. As the number of people increases, crowding generates pollution, destroys more habitats and uses up natural resources. Nowadays there are 6.2 billion people and experts predict that there will be 9.3 billion people in 2050. The question is how many people this planet is able to bear.

Although rates of population increase are now much slower in the developed world than in the developing world, we can’t assume that the developing countries have larger impact on the environment, because there live more people. In fact, because larger amounts resources per person are used in the developed nations, each individual from the developed world has a much greater environmental impact than does a person from a developing country. There something must be done, because if this keeps on, there will be no future, and we can’t live only of the present.

The most important factors necessary to lower population growth rates are democracy and social justice. Studies show that population growth rates have fallen in developing areas where several social conditions exist. Literacy rates have increased there and women receive economic status equal to that of men, so they aren’t dependent on men and they can make own reproductive decisions.

Global warming

Certain gases in the Earth’s atmosphere permit the Sun’s radiation to heat the Earth. These gases keep back a percentage of the infrared (infračervené) energy radiated back out by the Earth. This is called the greenhouse effect. These gases are primarily carbon dioxide, methane, nitrous oxide and water vapor. They are helping to maintain warm temperatures. Without them an average temperature would be –18°C. But if the concentration of these gases rises, they trap more heat, causing worldwide temperatures to rise

Within the last century, the amount of carbon dioxide in the atmosphere has increased dramatically, largely because people burn vast amounts of fossil fuels (coal and petroleum). Average global temperature has increased by about 0.6 Celsius degrees during the last century. It is said that at least half of the temperature increase can be attributed to human activity. Scientists predict that unless dramatic action is taken, global temperature will continue to rise by 1.4 to 5.8 Celsius degrees.

The consequences of the increase in temperature may be devastating. Scientists have already detected a 40 percent reduction in the average thickness of Artic ice. If the world’s keeps to melt, there will be a rise in the sea levels and it will inundate a number of low-lying islands and coastal cities.

If we want to stop this trend, we must stop production of the greenhouse gases and use other fuels which wouldn’t make such a damage.

The Ozone layer

The ozone layer is a thin band (vrstva) in the stratosphere serving as a shield of the Earth from the Sun’s harmful ultraviolet rays. In the 1970s scientists discovered that chlorofluorocarbons (CFCs) – chemicals which were used in refrigeration, air-conditioning systems and aerosol sprays – destroy the ozone layer. The molecule of chlorine is able to destroy more molecules of ozone, because chlorine isn’t affected by the reaction with ozone. So even now, when we don’t use CFCs, molecules of chlorine are destroying ozone and they will continue to for many decades.

The consequences of continued depletion of the ozone layer would be dramatic. Increased ultraviolet radiation would lead to a growing number of skin cancers and cataracts (šedý zákal) and also reduce the ability of immune systems to respond to infection. Also the marine plankton, which breaks down carbon dioxide, would decline. So it would increase the amount of carbon dioxide and thus to global warming. And it is also thought that global warming helps to destruction of the ozone layer.

If we want the ozone hole to close, we can’t release any more chemicals which destroy the ozone layer. Some steps have been made, for instance in 1987 the Montreal Protocol set specific targets for all nations to achieve in order to reduce emissions of these chemicals. We must also reduce the emission of the greenhouse gases to stop global warming.

My actions for the environment

I think that there should be more information to people about the environment, what they could and should do to help the good thing. As for me, I sort garbage, use the public transport and don’t burn any garbage at home. I would do more if I would know what else I could do as a person. And I also think that the industry have to make big steps in order to keep us on this planet and even to keep this planet alive.