The Global Warming Potential is a relative measure of how much heat can a greenhouse gas (GHG) hold for a determined period of time, in comparison to the CO₂ as a reference gas. Hence, if a gas has a GWP for 100 years of 10, it means that emitting one tone of this gas is equivalent of emitting 10 tones of carbon dioxide.

Source: Intergovernmental Panel on Climate Change