How carbon footprint of households is affected by the Japan's new policy to raise birthrate and income?

In 2015 the government of Japan introduced a set of policies to realize “A Society in Which All Citizens are Dynamically Engaged.” These policies, aiming to overcome barriers to economic growth, will involve measures... [ view full abstract ]

In 2015 the government of Japan introduced a set of policies to realize “A Society in Which All Citizens are Dynamically Engaged.” These policies, aiming to overcome barriers to economic growth, will involve measures focusing on the birth rate and employment. It would be expected, however, that increases in population and household income lead to carbon footprint associated with household consumption as indicated by some previous studies. Considering that in 2016 Japan also ratified the Paris Agreement reducing greenhouse gas emissions (GHG) toward 2030, it is now vitally important to take such economic policies from an environmental perspective into account as well.

             Therefore, this research seeks to estimate the carbon footprint of Japanese households in 2030 regarding structural changes in the population, household, and employment based on the “Dynamically Engaged Citizens” policies. Additionally, this research aims to examine the trade-off between the policies and the GHG Mitigation Target on the Paris Agreement.

              We conducted Environmentally Extended Input-Output Analysis using the Japan input-output table (JIOT) with the National Survey of Family Income and Expenditure (NSFIE) and the population statistics of Japan, in order to quantify the domestic carbon footprint of household (embedded GHG emissions generated in Japan). The NSFIE is a consumer expenditure survey of Japan, describing the average consumption expenditures among various household attributions such as household size, household income, and number of labors in household. Firstly, the household expenditures of six householder age groups (20s, 30s, 40s, 50s, 60s, and 70s and older) were obtained from the NSFIE of 2009. Then, we mapped these expenditures according to the consumption items of NSFIE onto the commodity sectors of the JIOT in order to calculate the household carbon footprint using the carbon footprint intensity (unit expenditure of carbon footprint) reported in the Embodied Energy and Emission Intensity Data for Japan Input-Output Tables (3EID). Secondly, we estimated an increase in the households of parents with children from 2016 to 2030 because of the recovery of birth rate associated with the Dynamic policies from the Business as Usual scenario reported by the population statistics (BaU). Thirdly, the additional household expenditures expected by the policies was distributed to the household expenditures of household attributions in 2030 as increases of children in household. 

            The results revealed that the domestic carbon footprint of household is expected to be larger than the Mitigation Target on the Paris Agreement at 33%, since the structure of household expenditure changes due to increases in the number of children and the share of double-income households. This indicates that Japan needs to reduce an “additional 6.3%” of the household carbon footprint in 2030 compared to the case of BaU in order to meet the mitigation target if the Dynamic policies is implemented as expected. More detailed methodology and discussion in this research will be presented at the conference.