What is carbon dioxide equivalent (CO2e)?

Carbon dioxide equivalent (CO₂e) is a single unit metric used to harmonise emissions from many different greenhouse gases based on their Global Warming Potential (GWP). In greenhouse gas accounting, CO₂e is more accurate than CO₂ alone because it covers the GWPs of all greenhouse gases that capture heat and warm our planet's atmosphere. For example, in a 100-year-period, methane traps 28 times more heat than CO₂, giving it a GWP of 28 CO₂e.