GLOBAL WARMING: A THREAT

Global warming is the term used to describe a gradual increase in the average temperature of the Earth′s atmosphere and its oceans, a change that is believed to be permanently changing the Earth′s climate.

''Over the past 50 years, the average global temperature has increased at the fastest rate in recorded history .And experts see the trend is accelerating .All but one of the hottest years in NASA′s 134 year record have occurred since 2000. Global warming occurs when carbon dioxide and other air pollutants and greenhouse gases collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth′s surface Normally, the radiation would escape into space but these pollutants, which can last years to centuries in the atmosphere , trap the heat and cause the planet to get hotter.That is what is known as  the green house effect.''

''In the United States, the burning of fossil fuels to make electricity is the largest source of heat trapping pollution , producing about two billion of carbon dioxide every year. Coal burning power plants are by far the biggest polluters.The country′s second largest source of carbon pollution is the transportation sector, which generates about 1.7 billion tons of carbon dioxide emission a year.''

Consequences of global warming are

• Melting glaciers,early snow melt and severe severe droughts will cause more dramatic water shortages and increase the risk of wildfires.

• Rising sea levels will lead to coastal flooding on the Eastern Seaboard, especially in Florida , and in other areas such as the Gulf of Mexico.

''• Forests, farms , and cities will face troublesome new pests , heat waves , heavy downpours and increase flooding. All those factors will damage or destroy agriculture and fisheries.''

• Disruption of habitats such as coral reefs and Alpine meadows could drive many plant and animal species to extinction.

• Allergies, asthma and infectious disease outbreaks will become more common due to increased growth of pollen producing ragweed , higher levels of air pollution and the spread of conditions    favorable to pathogens and mosquitoes.