1. Our fragile planet Done by Maria Elagina

2. The Greenhouse effect The air in the greenhouse is warm for a longer period as it is closed and none of the outer space air enters it. The air in the greenhouse is warm for a longer period as it is closed and none of the outer space air enters it. It is important to note here that greenhouse gases can trap the heat for as long as years. This heat when trapped in earth’s atmosphere results in global warming. In order to control or stop global warming it is imperative to control the release of greenhouse gases in the atmosphere. The most common and with largest quantity in the atmosphere, carbon dioxide is the threatening greenhouse gas. It is important to note here that greenhouse gases can trap the heat for as long as years. This heat when trapped in earth’s atmosphere results in global warming. In order to control or stop global warming it is imperative to control the release of greenhouse gases in the atmosphere. The most common and with largest quantity in the atmosphere, carbon dioxide is the threatening greenhouse gas.

3. What we have to do to save the planet: 1: Plan more trees: Trees absorb carbon dioxide and in return release oxygen in the atmosphere. Hence, more and more trees should be planted. 1: Plan more trees: Trees absorb carbon dioxide and in return release oxygen in the atmosphere. Hence, more and more trees should be planted. 2: Stop Deforestation: By cutting more and more trees we not just increase air pollution, we also increase the chances of soil erosion. With fewer trees around, more carbon dioxide will remain in the atmosphere. These greenhouse gases can increase the global warming. 2: Stop Deforestation: By cutting more and more trees we not just increase air pollution, we also increase the chances of soil erosion. With fewer trees around, more carbon dioxide will remain in the atmosphere. These greenhouse gases can increase the global warming. 3: Use organic food: We should avoid using normal food articles and go for organic food. Organic food is grown without any chemicals in it. Hence, it helps us to fight against water pollution. 3: Use organic food: We should avoid using normal food articles and go for organic food. Organic food is grown without any chemicals in it. Hence, it helps us to fight against water pollution. 4: Use cloth bags: While we go for shopping, we should carry our own cloth bags. This will discourage the use of plastic bags. Plastic bags only add up to garbage. When burnt, they release harmful greenhouse gases in the atmosphere. 4: Use cloth bags: While we go for shopping, we should carry our own cloth bags. This will discourage the use of plastic bags. Plastic bags only add up to garbage. When burnt, they release harmful greenhouse gases in the atmosphere. 5: Use recycled paper: Instead of going for new paper supplies every time, we should go for recycled paper as this will save trees from getting cut down. 5: Use recycled paper: Instead of going for new paper supplies every time, we should go for recycled paper as this will save trees from getting cut down.

4. Damage to the ozone layer Scientists began to investigate the ozone layer in the 1970’s, it wasn't until the mid 1980’s that alarm bells started to ring. Concentrations of ozone appeared to be dropping in certain areas of the world (the layer was starting to thin-out). The cause of this reduction was thought to be man-made. The images below highlight the Ozone depletion over the Southern Hemisphere 1980–1991 Scientists began to investigate the ozone layer in the 1970’s, it wasn't until the mid 1980’s that alarm bells started to ring. Concentrations of ozone appeared to be dropping in certain areas of the world (the layer was starting to thin-out). The cause of this reduction was thought to be man-made. The images below highlight the Ozone depletion over the Southern Hemisphere 1980–1991 There is a layer of ozone high up in the atmosphere which shields the Earth from the sun's harmful UV rays, these rays can lead to an increase in skin cancer.

5. Acid rain

6. The weak acid in rainwater can eat away the limestone in buildings and statues. Limestone is an alkali. The weak acid in rainwater can eat away the limestone in buildings and statues. Limestone is an alkali. Rain can also react with the waste gases sent out by power plants, factories, and cars. Such gases can be carried great distances by the wind. The they fall as weak sulfuric acid and nitric acid, so they are called acid rain. After a time, lakes and streams are slowly poisoned by the acid rain, threatening plants and wildlife. People are trying to reduce the waste gases pored out by industrial nations or to make them less harmful. Rain can also react with the waste gases sent out by power plants, factories, and cars. Such gases can be carried great distances by the wind. The they fall as weak sulfuric acid and nitric acid, so they are called acid rain. After a time, lakes and streams are slowly poisoned by the acid rain, threatening plants and wildlife. People are trying to reduce the waste gases pored out by industrial nations or to make them less harmful. Two of the main threats to our atmosphere are acid rain and the “greenhouse effect”. They are both caused by gases sent out by power plants, factories, and cars. Two of the main threats to our atmosphere are acid rain and the “greenhouse effect”. They are both caused by gases sent out by power plants, factories, and cars. Scientists are not in agreement on how much damage is done by acid rain. The trees in this picture have been damaged severely. Scientists are not in agreement on how much damage is done by acid rain. The trees in this picture have been damaged severely.

7. Web-links www.kniga.org www.wikipedia.org Thank you for watching