Q. What do you understand by global warming?
The Global warming is the increase in the temperature of the planet due to accumulation of some gases in the atmosphere, especially gases that maintain the solar energy reflected by the planet surface. The major gas that causes the global warming is CO2, carbon dioxide but other gases act as "warming gases" too, like methane, CH4, and nitrous oxide, N2O. The embroidered increase of carbon dioxide in the atmosphere has been caused by the burning of fossil fuels (mainly oil and coal) in industrial and urban societies and by forest fires (It is important to note that the natural warming provided by gases of the atmosphere is fundamental for the maintenance of the planet temperature).
The Predictions of studies sponsored by the United Nations stated that the global warming may cause life-threatening transformations to the planet in the near future. The Countries that are the biggest emitters of carbon dioxide, like the United States and China, though, systematically ignore the warnings and continue to largely contribute to the danger. Global warming is one of the most polemic environmental issues today.