CO2e emissions and why is this used instead of CO2?

CO2e Emissions 

CO2 emissions are exactly what it says, but in order to get the full carbon impact of global warming potential (GWP) CO2e is used or sometimes referred to as carbon dioxide equivalent.

This is a metric measure that is used to compare emissions from various greenhouse gases, thus giving a far more realistic picture of the GWP impact.

Greenhouse Gases

When CO2 figures are presented this is only part of the story. As can be seen on the figure to the left, GWP factors are included for all greenhouse gases. For example, 1KG of Methane can be expressed as 25KG of CO2e.