Greenhouse gas emissions, such as carbon dioxide, are created in part by burning oil and coal for transportation and electricity.

VOA: special.2009.12.26

The gas is mainly methane. It produces half the carbon dioxide of other fossil fuels.

VOA: special.2009.10.23

The gas may then turn into something else such as carbon dioxide.

VOA: special.2009.12.30

Trees also capture carbon dioxide, a gas linked to climate change.

VOA: special.2009.09.01

Climatologists say that greenhouse gas emissions, such as carbon dioxide from burning oil and coal, contribute significantly to global warming.

VOA: standard.2009.11.09

Greenhouse gas emissions such as carbon dioxide are thought to be a major cause behind rising temperatures that have lead to extreme weather and food shortages.

VOA: standard.2009.09.28

"When the gas comes off the digester, it has not only methane in it it also has carbon dioxide And it has a trace of hydrogen sulfide."

VOA: standard.2010.02.23