The phrase "global warming" has become familiar to many people as one of the most important environmental issues of our day. Being kept warmer may sound appealing to those who live in cool climates, but an increase in global temperature will lead to a global climate change. If the change was small and occurred slowly, than we would be able to adapt to it, but with the world's industry changing so rapidly it is hard for the environment to do just that.
The earth's surface temperature has risen about 1 degree Fahrenheit in the past century and increased warming during the past two decades. Global warming refers to an average increase in the Earth's temperature, which in turn causes changes in climate. Energy from the sun drives the earth's weather and climate, and heats the earth's surface and in turn the earth radiates energy back into space. Greenhouse gases, such as water vapor, carbon dioxide, and other gases, trap some of the outgoing energy, retaining heat. Without this natural greenhouse effect temperatures would be much lower than they are now. This is how problems arise when greenhouse gases increases. .
The basic idea of global warming can be explained by "considering the radiation energy from the sun which warms the Earth's surface and the thermal radiation from the Earth and the atmosphere which is radiated out to space" (qtd. in Houghton: 10). Also see diagram 1 for a visual explanation. .
The greenhouse effect is much to blame for global warming. Heat from the sun passes through the atmosphere and it warms up the surface of the Earth. As the surface warms up, it emits heat in the form of infrared radiation. Some of this heat is than trapped by the atmosphere. The greenhouse gases than make the atmosphere trap this radiation causing it to warm up the Earth more than it should. Gases, such as carbon dioxide, methane, water vapor and nitrous oxide all build up in the atmosphere.
