Evaluation of carbon dioxide equivalent values for greenhouse gases: CEWN as a new indicator replacing GWP

A new indicator, the CEWN (Carbon Dioxide Equivalent Warming Number), is proposed as an alternative to the GWP (Global Warming Potential). CEWN is a metric where the global warming by the emission of gases is compared unifying the removal rate of each gas from the atmosphere, using carbon dioxide as a reference. To comply with the basket system of the Kyoto Protocol, GWP is used with a 100-year time horizon, making it unsatisfactory for the evaluation of long-lived compounds. As the removal rate from the atmosphere depends on the lifetime, the CEWN presents a fair assessment of the relative global warming.