Common arguments
Is CO2 too small a part of the air to matter?
CO2 is measured in parts per million, which sounds far too small to change anything. Here is why that does not hold up.
Why it sounds plausible
CO2 is measured in parts per million, which sounds far too small to change anything.
The simple answer
Small concentrations can have large effects.
The fuller explanation
A gas does not need to be abundant to matter. CO2 absorbs infrared radiation at specific wavelengths, which changes Earth's heat balance. Many powerful substances act strongly at low concentrations.
Bottom line
CO2 is small by percentage, but important by effect.
Quick answers
Frequently asked
CO2 is small by percentage, but important by effect.
Small concentrations can have large effects.