Swamps and marshes emit significant amounts of the greenhouse gas methane. Although it is less prevalent than carbon dioxide, methane traps about 25 times more infrared radiation per molecule. Methane is produced by many factors, including the cutting and burning of forests and grasslands, which causes soil microbes to alter their activity and release methane. It is also produced by termites, which release enough methane to contribute significantly to the total amount in the atmosphere. In recent years, global atmospheric methane levels have increased erratically, sometimes by one percent per year.
Photo Patrick Zimmerman, Copyright © University Corporation for Atmospheric Research (UCAR). Copyright © 2008 TerraNature Trust. All rights reserved. |
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