Introduction to Global Warming Climate change is neither new nor unusual. Throughout the history of the earth, the average surface temperature, climate and greenhouse gas concentrations have changed, sometimes gradually other times quite sharply. During the past 10,000 years the earth has been in an interglacial period with a fairly stable climate, surface temperature, and greenhouse gas concentration1. The problem that has arisen in recent times is when scientists analyze the past 150 years, especially the last 50. Scientists have found an increased greenhouse gas concentration, making the 20th century the hottest in the last 10,000 years.Although the earth has undergone periodic changes known as global cooling and global warming, today’s global warming is unique, due to human influences. The greenhouse effect is essentially gasses in the atmosphere trapping heat, rather like a car window does in the summer. The major heat trapping gasses found in the atmosphere are; CO2 and water vapor- which are found in large quantity, 03(ozone), ch4(methane), and N2O(nitrous oxide)-which are better heat trappers but found in smaller quantity, CFC’s and PFC’s- which are very potent and destroy ozone. The rapid elevation of these gasses in the past fifty years have been the cause for concern of scientists calling it a global warming problem.Global warming is a natural process as well as a human assisted process. Solar flares and sunspots along with natural elevation of greenhouse gasses due to volcanic activety are the natural causes for global warming. Dr. Judy Lean, a leading astrophysicist, looked at global warming trends from 1860 to the present day. Her research has found from 1860 to 1970, global warming was largely due to natural sources. But from 1970 to the present natural sources accounted for only one-third the increase while human influence accounted for the remaining two-thirds of the increased greenhouse ...