Multigas Mitigation: An Economic Analysis Using GRAPE Model

Future global warming may depend strongly on the potential for abating emissions of greenhouse gases (GHGs). Flexibility in implementing climate change mitigation policies can significantly reduce mitigation costs and has three dimensions; space, time and gas species. Therefore, multiple greenhouse gas reduction flexibility should be considered. The emission and reduction potential of CO2 and non-CO2 GHGs are assessed here using an integrated assessment model under climate change targets. The implications on gas life as well as abatement timing uncertainty on costs, technological availability, etc. are discussed. The introduction of additional multigas reductions will cut the economic burden of achieving a given climate change target. The conclusions are threefold; (1) Multigas mitigation is a cost effective strategy compared to CO2-only mitigation under the same climate target, (2) CO2 mitigation is expected to lead to ancillary reductions in CH4, N2O and SOx emissions, and (3) There is great uncertainty in the assessment of non-CO2 GHG mitigation opportunities.