Agreement has been reached in the United Nations’ climate negotiation process that from a scientific perspective, the global average temperature should not exceed two degrees above the preindustrial level. The sum of bottomup targets pledged by individual countries, however, does not reach such an ambitious global target and a new framework to reach the target is still under debate. In the first place, a temperature limit to be avoided cannot be determined solely by science but it must involve the value judgment of society. There is also a large scientific uncertainty between temperature targets and emission targets. Furthermore, linkages between climate change policy and other global issues, such as a potential conflict between large‐scale deployment of biomass energy versus food and biodiversity issues, are insufficiently understood.
In this study, we adopt a risk management standpoint to tackle this problem. Namely, we comprehensively assess risks due to the impact of climate change and climate change policies, explicitly deal with uncertainties, utilize the best available information, and consider every possible condition and option. We regard the problem as one of decision‐making at the human level, which involves social value judgments and adapts to future changes in circumstances. We are conducting research under the following five themes: