Global warming can be explained in simple words as the increase in temperature of the lower layer of the atmosphere. Green house gases like carbon-dioxide, methane and nitrogen-oxides have the capacity to hold the outgoing energy in terms of heat, released from the surface of the earth. Even the water-vapour in the atmosphere has the capacity to hold the heat released from the surface of the earth. Due to these reasons the temperature on the surface of the earth gradually increases which is known as Global warming. Industrialization and Urbanization are the major causes of Global warming. Combustion of fossil fuels like oil and coal in the thermal power plants, industries and automobiles often releases green houses gases like carbon-dioxide which increases the atmospheric temperature.
Global warming is a serious threat for the natural environment as it will change its natural cycle and will ultimately destroy it. Rise in atmospheric temperature and melting of snow in the arctic region are some of the examples of the direct effects of global warming on the environment.
What if Global warming continues?
If Global warming continues then some of the largest urban centers and industrial areas like Shanghai, New York and Tokyo would be under sea-water in the near future. The solution for this problem is not quite easy because the developed country's economies are strongly tied with the hydrocarbon fuel which is one of the major causes of Global warming.
However, certain control measures can be taken to prevent such problems in future. By using alternative sources of energy, the emission of carbon-dioxide can be decreased. The non-conventional energy resources like solar, wind, tidal, geo-thermal or bio-based energy resources can serve as a good alternative. Thus by using such non-conventional sources of energy even the environmental pollution can be curbed upto a great extent.