Carbon sink quantification aids for achieving the zero-emission goal: A case study in Japan

The Japanese government has issued its zero-GHG emission goal by 2050 and a short-term emission mitigation goal for 2030; however, some local communities face difficulties in making detailed mitigation plans. This study provided details on modelling and mapping carbon uptake (i.e., sinks from forest lands) at a high spatial resolution level in Fukuoka Prefecture in 2015. A scenario analysis was then conducted on the net carbon emissions by 2050 to discuss the achievement of the zero-carbon emission goal. The carbon sinks from forest land remaining in Fukuoka were estimated at a high spatial resolution level (forest managed-team level) for the year 2015. The carbon sinks from the pools (living biomass, deadwood, litter, and mineral soil) were approximately 2615 Gg CO2 yr −1. Carbon sinks from other forests (public-owned and private-owned) accounted for approximately 88.2%. The national forest carbon sinks account for approximately 11.8% of the total. The results of the BAU scenario showed that it was impossible to achieve its goal by 2050 without additional efforts on emission mitigation and uptake. As a result of the implemented scenarios, the goal could only be achieved by achieving the short-term mitigation goal for 2030 (3.2% decreased annually from the previous year), maintaining this mitigation trend until 2050, and increasing the level of carbon sink addition (5.3% annually increased from the previous year). This work will provide a precedent to support policymakers from global cities to clarify their net carbon emissions and make essential carbon mitigation and uptake goals.