Carbon neutral = Carbon offset

A carbon offset is a reduction in carbon dioxide emissions from a third party, aimed at cancelling out (offsetting) the emissions arising from a particular activity. The aim is to reduce greenhouse gas emissions and thereby combat global warming. Proponents claim that all emissions can be offset and made "carbon neutral".

Carbon offsets can be purchased by individuals, businesses and governments from a variety of commercial and non-commercial organisations. For example, the UK government purchased offsets for the air travel required for the 31st G8 summit. Offset activities can vary widely; the most frequent are planting trees and energy conservation activities.

Carbon offset providers often provide a "carbon calculator" for individuals to estimate the carbon dioxide emissions arising from their consumption of electricity, petrol, air travel, etc - a sort of ecological footprint for global warming. Some controversy surrounds carbon offsets due to the uncertainty about the science and accounting of sequestration coupled with criticism from community groups living near projects who have in some cases been adversely affected.

參考資料: Wikipedia

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