What is the Greenhouse Effect and the Importance of Methane to Climate Change

By Steve Evans

The greenhouse effect, also called the "greenhouse phenomenon" or "global warming", has recently been receiving a great deal of scientific and popular attention. The term refers to a cause-and-effect relationship in which "heat blanketing" of the earth, due to trace gas increases in the atmosphere, is expected to result in global warming.

By global warming we mean an increase in the average temperature of the planet. Actually global warming is rather a confusing term because global warming does not mean that everywhere will be hotter all of the time, it just means that on average the globe will be warmer.

Now we just mentioned that “heat blanketing” is taking place, and that this is due to trace gases in our atmosphere. There are a number of so called ‘trace’ gases, which simply means gases that are present in the atmosphere at low levels, such that there is only a trace present (a small amount in proportion to the other gases). So it is these trace gases that are producing an effect which is like wrapping the world in a blanket. Just like any blanket, it has a net effect which holds the heat in.

These trace gases are increasing as the result of human activities. Scientists know this. It is easily measured historically by analyzing things like pack ice which was deposited in layers which layers can be readily dated and go back hundreds of thousands of years.

Carbon dioxide (chemically shown as CO2, which is simply a chemist’s shorthand way of telling us that it is a molecule made up from two Oxygen (O) molecules to each Carbon (C) molecule), is a trace gas.

The principal gases in approximate order of importance, are carbon dioxide, methane, the chlorofluorocarbons (considered collectively) and nitrous oxide.

Carbon dioxide is the trace gas scientists believe is contributing most to the "heat blanketing" and currently receives the most attention.

However, Carbon Dioxide is not the only trace gas which is implicated in climate change and methane is another which some have estimated to be over a third as much as that of carbon dioxide.

Gas from natural sources, cows and other ruminants, and natural sources where natural decomposition by fermentation produces methane, all contribute to the blanketing which is the cause of the greenhouse effect.

However, human activity is also responsible for a lot of methane gas production and Municipal Solid Waste Landfills have in turn been recognized to be a source of methane which is contributing to the atmospheric buildup.

However, the magnitude of the landfill methane contribution and the overall significance of landfill methane to the greenhouse effect have been uncertain, and the subject of some debate.
But, as time goes on the evidence becomes stronger, and the fact of climate change is now accepted by the vast majority of scientists working in this field.

So, it appears that methane (using US waste generation data and remembering that the methane from United States landfills is a very large quantity) makes an important net contribution to the greenhouse phenomenon.

Landfill produces a lot of landfill gas which is largely methane. Measures to reduce landfill methane emissions are thought to be among the most economical steps which could be taken to address a component of this problem.

So now you know more about this subject, and we hope you appreciate the danger posed by uncontrolled climate change. We have explained, and hopefully ‘demystified’ some of these details – so now you can visit our web sites armed with enough knowledge to help you to find out more...

Steve Evans is a regular contributor of environment related articles. There are more essential details about climate change and the importance of methane at The Landfill Gas Web Site See also our New Blog about renewable power sources which do not cause global warming: Renewable Energy News