2 research outputs found
High-Resolution Inventory of Japanese Anthropogenic Mercury Emissions
Heavy metals like mercury that are emitted into the environment
remain there indefinitely, posing a long-term threat to both the environment
and human health. Elemental mercury is volatile and is in gaseous
form, and because of the long residence time, transported over long
distances. Comprehensive control of mercury emissions therefore remains
an important international issue. The crucial steps for designing
effective approaches for such control include the quantification of
mercury emissions by sources and the identification of geographical
characteristics of the emissions. In this study a detailed, high-resolution
inventory of Japanese mercury emissions in 2005 was developed to improve
understanding of their geographical distribution. Proceeding from
a national emissions inventory per source category, emissions were
spatially allocated with increasing geographical resolution in a stepwise
procedure using statistics from geographic information resources,
yielding mercury emissions per prefecture, per municipality and per
grid cell of approximately 1 × 1 km. The five prefectures with
the highest emissions were Fukuoka, Yamaguchi, Hyogo, Oita, and Hokkaido,
accounting for 35.2% of all emissions. In each prefecture a small
number of municipalities account for a major share of emissions. Distribution
by grid cell is characterized by a concentration of 50% of all emissions
in a mere 32 of the 255 954 grid cells over which emissions
are distributed in this study. It was also quantitatively confirmed
that use of larger grid cells leads to greater uncertainty in emissions
distribution. Problems with data collection are clarified and measures
to improve the accuracy of future estimation are proposed
High-Resolution Inventory of Japanese Anthropogenic Mercury Emissions
Heavy metals like mercury that are emitted into the environment
remain there indefinitely, posing a long-term threat to both the environment
and human health. Elemental mercury is volatile and is in gaseous
form, and because of the long residence time, transported over long
distances. Comprehensive control of mercury emissions therefore remains
an important international issue. The crucial steps for designing
effective approaches for such control include the quantification of
mercury emissions by sources and the identification of geographical
characteristics of the emissions. In this study a detailed, high-resolution
inventory of Japanese mercury emissions in 2005 was developed to improve
understanding of their geographical distribution. Proceeding from
a national emissions inventory per source category, emissions were
spatially allocated with increasing geographical resolution in a stepwise
procedure using statistics from geographic information resources,
yielding mercury emissions per prefecture, per municipality and per
grid cell of approximately 1 × 1 km. The five prefectures with
the highest emissions were Fukuoka, Yamaguchi, Hyogo, Oita, and Hokkaido,
accounting for 35.2% of all emissions. In each prefecture a small
number of municipalities account for a major share of emissions. Distribution
by grid cell is characterized by a concentration of 50% of all emissions
in a mere 32 of the 255 954 grid cells over which emissions
are distributed in this study. It was also quantitatively confirmed
that use of larger grid cells leads to greater uncertainty in emissions
distribution. Problems with data collection are clarified and measures
to improve the accuracy of future estimation are proposed