GLOBAL WARMING AND THE OZONE LAYER

GLOBAL WARMING AND THE OZONE LAYER

1.The sun gives us heat and light. The heat warms the surface of the Earth during the day. The Earth, in turn, radiates the heat back into the atmosphere. Most of the radiated heat escapes the atmosphere but some of it's reflected back because of certain 'greenhouse gases' in the atmosphere. This leads to a gradual increase in the Earth's overall temperature.

2.This Greenhouse Effect is just like the process that takes place inside your car when it is parked in the sun on a hot day. The heat that is trapped inside the car makes it much hotter inside than outside. The glass panes prevent all the heat radiated inside the car from escaping.

3.The main greenhouse gas is carbon dioxide but others like methane(the compound in CNG or Compressed Natural Gas), nitrous oxide and chlorofluorocarbons or CFCs also contribute to the greenhouse effect.

4.Burning of fossil fuels produces energy which we use, but also produces carbon dioxide which contributes to the greenhouse effect.

5.In a year, an average car emits five tons of carbon dioxide into the air. Multiply this by the number of automobiles in the USA alone (about one hundred and twenty million) and you will realize the amount of pollution caused only by cars.

6.The total number of miles driven by cars and other vehicles in the western  industrialized countries in 1985 was 2.5 trillion miles! If you don't know how much that is, it is 2.5 followed by twelve  zeros or almost half a light year!

7. In the year 2002, the average carbon emission per person in America was seventeen times that in India- in the USA, carbon emission was 5.2 tons per person, while in India it was 0.3 tons per person.

8.Of all the fossil fuels, coal produces the most greenhouse gases on burning, while natural gas produces the least. That is why vehicles powered by CNG, or Compressed Natural Gas, are relatively pollution free.

9.If nothing is done about the greenhouse effect, average temperature across the world could increase by 1.5-4.5*C in about thirty years. And more devastatingly, the rise would be more near the poles than near the tropics. This increase in temperature, called global warming, will have very tragic  consequences for the Earth and for all of us.

10.storms and hurricanes will become more frequent and stronger as the oceans become warmer and lose more water by evaporation. There will be droughts and heat waves causing a lot of loss of life.

11.Sea levels will rise by an estimated twenty to fifty  centimeters by the year 2050. This means coastal areas and rivers estuaries could go under water, causing great devastation. Bangladesh and the Nile delta, two areas under risk, have high population densities.

12.If the sea levels continue to rise, most of the coral islands in the Indian Ocean will disappear under the sea.

13.Global warming has also caused Arctic temperatures to rise sharply. Siberia and Alaska are already 2-3*C warmer now than they were in the 1950s. The extent of ice around the North Pole has shrunk by about twenty percent in the past 30 years.

14.Though warmer temperatures may be more productive for fisheries and oil exploration, their effect on animal habitat could be devastating. For instance, polar bears could become extinct if the summer ice cover disappears.

15.Every Antarctic spring, a 'hole' appears over  Antarctica, which results in the destruction of over seventy percent of the ozone over the Antarctic.

16.Ozone is a molecule, made up of three oxygen molecules, which acts as a shield that protects the Earth from the harmful  ultraviolet rays of the sun. Overexposure to ultraviolet rays can cause skin cancer in humans and is also harmful for animals, especially marine life like plankton.

17.The ozone layer extends in the stratosphere, which is the region of the atmosphere extending from about ten kilometers to fifty kilometers above sea level.

18.The main reason for the  thinning of the ozone layer is the use of CFCs or chlorofluorocarbons. These are chemicals used for cooling in the air-conditioners and refrigerators.

19.In 1987, many nations of the world adopted the Montreal protocol to phase out the use of CFCs. Now, most nations have either stopped or drastically reduced the use of CFCs in refrigeration.

20.Volcanic eruptions send out large amounts of sulphur dioxide and volcanic ash into the atmosphere. The eruption of Mount Pinatubo in the Philippines in 1991 gave out enough ash into the atmosphere to lower temperatures around the globe for the next two years.

IF YOU HAVE ANY QUIRES DO ASK I'LL TRY MY BEST TO ANSWER IT.