1 Design of Georeference-Based Emission Activity Modeling System (G-BEAMS) for Japanese Emission Inventory Management

It comes near to stating the obvious to say that an emission inventory is essential to understanding the status of pollutant emissions and to designing comprehensive countermeasures for mitigating them. To improve the accuracy of an inventory and to allow data management, it is necessary to develop methods for systematizing an emission inventory. We developed an emission inventory system, the Georeference-Based Emission Activity Modeling System (G-BEAMS). The primary function of our system is to estimate the spatial and temporal distributions of chemical emissions and air pollutants in Japan. It uses mathematical functions to estimate emissions; emissions maps to show differences over time; and databases of emission factors, activity data, spatial weighting factors, and temporal weighting factors. G-BEAMS standardizes emission-source categories and geographic position. Unfortunately, there is no Japanese standard source classification for an emission inventory like the US SCC (Source Classification Code) or the EU SNAP (Selected Nomenclature for Air Pollution) code. Therefore, we coded our own classification by considering a combination of industries, production processes, and production technologies. Geographic positions were defined with polygonal, linear geometry or coordinate values on a GIS layer; each geometry has a unique index. Basic layers in the system were chosen with regard to the public availability of statistical data, including geographic position information. This standardization enables us to systematize procedures for compiling an emission inventory by both top-down and bottom-up approaches, and by spatially and temporally allocating estimated emissions