Image from http://www.androidworld.com/prod60.htm	THE PAST Before Seventy-five million years ago, the earth’s average temperature was about 10 degrees Fahrenheit or 5.6 degrees Celsius higher than it is now.  The climate was warm and humid.  The continents had not move to where it is now.  India and Asia were not joined; South America and Africa lay closer together and Australia was nearer to Antarctica.  20,000 years ago there was an ice age and the average temperature was about 9 degrees Fahrenheit or 5 degrees Celsius lower than it is today.  The continent was cover with ice.
In 1958, scientists began testing the volcanic mountain of Mauna Loa in Hawaii to determine the levels of carbon dioxide in the atmosphere.  This measurement is still continued in Hawaii. Tests have shown that CO2 (carbon dioxide) has increase about 0.4% a year from 315 ppm in 1958 to 353 ppm in 1990. 1990 was the hottest year out of the last century; with the year of 1991, 1983, 1987, 1988, and 1989 as the six warmest years in the last century.  1991 was the second hottest year in the past century; and the cause of it might have been eruption of Mt. Pinatubo.  Some of the ashes from the volcano went up into the atmosphere and block the sunlight.  Scientists predicted that after the ashes traveled up to the atmosphere; there will be two to three years of cooling down.  Then, the ash particles will fall back down to earth to worsen global warming.
After After the 1960s, the amount of methane in the atmosphere has increased one percent each year. For ten years, methane has been in the atmosphere, and it is 30 times more effective than carbon dioxide. Before the Ice Age ended around 13,000 B.C., most of the world’s surface was densely filled with ice and the massive ice rivers are known as glaciers.	Image from http://www.androidworld.com/prod60.htm
After years of warmth, scientists discovered the little Ice Age in the mid-1500s. With the record of the people living in Iceland, researchers were able to understand the result of warm and cold state. Between1650 and 1850 the Icelanders had difficulties, because they weren’t able to fish, the land was covered with ice for a couple of months in a year. They kept a record of when the temperature got warmer in 1880 and was relieved that they could extend their fishing seasons. It is believed that the earth was connected as one whole continent called Pangaea. Source: Global Warming: Focus on the Future.  26 July 2006 <http://globalwarming.enviroweb.org/‌sitemap.html>.