Abstract

Scientists are now more confident than ever that climate is changing due to greenhouse gas emissions from human activities, and that the impacts of the altered environment on society have already become apparent. Numerical simulations based on the Coupled Model Intercomparison Project Phase 6 (CMIP6) protocol, a design for climate change projection with numerical models for global environment (Eyring et al. 2016), are being conducted by leading climate modeling centers worldwide, and the product data are being distributed internationally. The Ministry of Education, Culture, Sports, Science and Technology (MEXT) launched the TOUGOU program in FY 2017 to develop numerical models to generate the CMIP6 projection data and utilize them to dynamical downscaling and impact assessment research (Figure 1). This special issue consists mainly of the studies conducted under the TOUGOU program and also contains research papers related to the program. We hope that this special issue contributes to grasping the progress made by the TOUGOU program in the field of climate change projection research.