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 > Water: A Scarce Resource > Deforestation and Desertification > Depletion of the Ozone Layer
dijous, 5 de juny de 2003
World Environment Day is commemorated each year on 5 June. This date was selected by the United Nations in 1972 in order to raise worldwide awareness of the need to protect and make improvements to the environment.
The World Environment Day theme selected for 2003 is 'Water – Two Billion People are Dying for It!'. It is hoped that this theme will make us aware of how important it is to safeguard and improve the quality of such a precious natural resource for future generations. This theme has been chosen in support of the United Nations also having designated 2003 as the International Year of Freshwater. This decision is a very necessary one, given that a vast majority of the world's population has no access to drinkable water. This lack of water, caused as a result of drought, poor use of water reserves and wasteful use of water resources, in addition to climate changes that have only just begun, has now become the source of a number of wars. It is also the source of illness, given that the consumption of contaminated water leads to illnesses such as cholera, which affects some 200 million people as well as leads to the death of two million people all over the world each year. The main international celebration of World Environment Day will be held in Beirut, capital of Lebanon, and is the first city in the Arab world to host this United Nations day. In addition, many cities and towns all over the world will also be celebrating with activities relating to the environment, such as street rallies, bicycle parades, green concerts, and tree planting.
 
Water: A Scarce Resource)
+ The World Environment Day theme selected for 2003 is 'Water – Two Billion People are Dying for It!'.
Although we live on a blue planet, with most of its land area covered by oceans and seas, we cannot deny that water is a scarce resource. Most of the water on Earth is not available for drinking: only three per cent of it is fresh water. In spite of everything, this small percentage ought to be enough to ensure that everyone has access to it. However, this unfortunately is not the case, given the fact that water is not properly distributed. It is used improperly and not enough care is given to make sure it does not become contaminated. These are three particularly important factors if we think about the fact that water is essential for life. Governments and institutions must make a greater effort to change this situation. Nevertheless, this cannot be an excuse for us evading our own responsibility. We can all do our part, particularly when it comes to the domestic use of water.
Deforestation and Desertification
+ Deforestation is a very serious environmental problem.
Another very serious environmental problem that must be addressed is deforestation, in other words, the gradual disappearance of our forests. This is certainly not a recent problem, as forests have been swept away for many centuries now. However, in recent decades this activity has increased in an alarming manner. What are the reasons behind it? There are several: climatic changes; an increased need for farm land; the pulp and paper industry; wars; forest fires…Furthermore, mass deforestation often results in desertification, as rainwater, when there are no forests, becomes runoff when there is nothing to retain it, which in turn causes soil erosion. Added to all that is the fact that indiscriminate tree felling contributes to a great extent to the greenhouse effect. We must bear in mind that the more trees we lose, the more oxygen we lose in the atmosphere. This is why in a few short days, 17 June will commemorate the day designated by the United Nations as World Day to Combat Desertification and Drought.
Depletion of the Ozone Layer)
+ The quantity of ozone in the atmosphere has been substantially reduced since the 1970s.
Ozone is a gas located in the Earth's atmosphere that forms a layer to protect us from the ultraviolet radiation coming from the Sun. During the 1970s, scientists discovered that the quantity of ozone in the atmosphere had been substantially reduced as a result of the presence of chemical compounds known as CFCs (chlorofluorocarbons). These compounds are used to produce the low temperatures found in refrigerators and air conditioning equipments, and are also used in aerosols, in the manufacturing of plastic containers and as solvents in the electronics industry. The most serious consequence of the depletion of the ozone layer is the increase in the number of registered cases of skin cancer and eye damage. Recently, there has been increased awareness of the extent of this problem, which has resulted in reductions to the use of these substances, which in certain instances have been substituted by other less harmful compounds. Nevertheless, eliminating CFCs from the atmosphere is not an easy task, and it could take up to one hundred years before we come close to achieving this goal. The first step is to find the way to completely eradicate these emissions.
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