Global warming is not a 20th century phenomenon. It has, in fact, occurred in the past more than once, along with periods of extreme cold known as the ice ages. With so much written and reported about global warming, sometimes it's difficult to detect which is fact and which is just part of scientific scare tactics. Here are some facts about global warming that might help:
What exactly is global warming? Global warming is basically the increase in the temperatures of the Earth's atmosphere, land masses and oceans. The Earth's surface temperature is at an average of 59F and over the last hundred years, this figure has risen to about 1F. By the year 2100, the average change in the temperature of the Earth could range from 2.5F to about 10F, enough to melt glaciers and polar ice caps.
The cause of global warming Global warming has and will always occur naturally. Why it has become such a concern in our lifetime is due to the fact that human activities and practices have contributed significantly to its occurrence and severity. With the advent of industrialization and careless environmental practices, we have caused the increase in the average global temperatures by contributing negatively to the greenhouse effect.
This began about 240 years ago, when the Industrial Revolution was born. As more and more fossil fuels in the form of oil were mined and burned, gases as the by-product of that process began to be released in the atmosphere. Currently, it is estimated that 75% of the increase in the carbon dioxide content of the Earth's atmosphere is caused by the burning of these fossil fuels.
Global warming and the greenhouse effect Global warming is related to changes in the Earth's greenhouse effect. Gases naturally occur in the Earth's atmosphere and act both to protect and retain heat. These gases include carbon dioxide, methane, nitrous oxide and water vapor. Of these, water vapor is the