They give off a lot of greenhouse gases (especially CO2) into the air. This warms the earth.

它们向空气中释放大量温室气体（尤其是二氧化碳）。这使得地球变暖。

youdao

Correction: the article originally misstated that methane, at least 21 times more potent than CO2, is the most potent of greenhouse gases.

更正：本文起初对甲烷的性能掌握有误——其温室效应是二氧化碳的21倍之多，是最强的温室气体。

youdao

When it comes to greenhouse gases many of us think first of CO2.

当涉及到温室气体，我们许多人首先想到二氧化碳。

youdao

This process of combining of water, cement paste, sand and rock creates an awful lot of CO2 gases - which are linked by some scientists to global warming - about five to 10% of the world's total emissions.

BBC: By Ian Hardy

The ruling rejected a position taken by the EPA during the Bush-Cheney administration that CO2 greenhouse gases were not air pollutants.

FORBES: Magazine Article

That methane and CO2 are greenhouse gases for example.

FORBES: Maybe Climate Change Just Really Isn't A Problem After All?