Carbon offset
A carbon offset is an attempt to lessen greenhouse gas emissions by compensating for CO2 which has already been released. For example, groups or companies may plant trees to offset travel pollution and to avoid deforestation. Trees help balance CO2 levels. Other offsets include solar, wind and biofuel energy projects. Some companies and non-profit groups sell these carbon offsets. You can essentially pay someone to reduce or remove global waming emissions in your name.
If you buy a carbon offset, the money is supposed to go to projects that reduce greenhouse gas emissions -- projects that would not have been possible without your money. Apparently this is not always the case and the efficacy and validity of carbon offsets are controversial. If you want to buy carbon offsets, do your research first.
Sources:
-- "Buy your way to carbon neutrality?" The Seattle Times, Sept. 23, 2007. http://seattletimes.nwsource.com/html/businesstechnology/2003897259_carbon23.html
-- "Carbon Offset," Wikipedia. Accessed Sept. 24, 2007. http://en.wikipedia.org/wiki/Carbon_offset
-- "Neutralize Your Pollution," FightGlobalWarming.com Web site published by Environmental Defense. Accessed Sept. 24, 2007. http://www.fightglobalwarming.com/page.cfm?tagID=270
