Development of a support tool for greenhouse gas emissions control policy to help mitigate the impact of global warming

We have been developing a policy support tool, AIM/impact[policy], for use in the integrated assessment of global warming control targets including the stabilization of greenhouse gas concentrations, economically efficient emissions paths to realizing these targets, and consequent impacts and risks of these targets. In this study, a quantitative assessment was made of climate changes and global warming impacts, as well as the timing of greenhouse gas reduction policies, under greenhouse gas stabilization constraints. An energy economic model estimating the optimal emissions path for greenhouse gases and an impact assessment model estimating the impacts of global warming in various fields caused by climate changes under this optimal emissions path were used in our assessment. In contrast to the business-as-usual case, our results showed that in order to maintain greenhouse gas concentrations at less than 500ppm (by volume), reduction volumes must be 3.0GtCeq/year by 2020 and 12.2 GtCeq/year by 2050, indicating an urgent need for a full-scale reduction system.