『Abstract
Annual emission map for NH3, NOx,
and SO2 within Osaka prefecture was shown
according to the EAGrid2000-Japan emission database. The median
emission of NH3, NOx,
and SO2 was 1.94, 24.8, 1.32 ton/km2/year,
respectively, while that at 11 passive sampling sites was 1.61,
17.3, 0.74 ton/km2/year, respectively. Monthly emission
for NH3 showed apparent seasonal trends, being high in summer
and low in winter. That for NOx and SO2 was slightly high in winter and low in summer
and constant through the year, respectively. Atmospheric concentration
of NH3, NO2, HNO3, and SO2 by the passive
method was compared with corresponding emission inventory. Average
concentrations of HNO3, SO2,
NH3, and NO2 in June
were 16-67, 23-135, 21-173, and 149-873 nmol/m3, respectively,
while those in October were 5-21, 16-72, 14-196, and 169-1,167
nmol/m3, respectively. The emission inventory flux
of SO2, NOx, and NH3 was calculated both within 1×1- and 3×3-km mesh.
It was a small difference between June and October for SO2 and NOx in the both meshes.
For NH3, emission flux in June was around
twofold of that in October. The NH3 correlation
between concentration and emission flux was excellent in the 1×1
km mesh, although somewhat decreased in the 3×3 km mesh. In the
case of NO2, the correlation for the 3×3
km mesh, however, was more increased than the 1×1 km mesh. The
correlation for HNO3 and SO2
was a small difference with the both meshes. Monthly concentrations
of NH3, NO2, HNO3, and SO2 were compared
with their corresponding gases emission at whole-year survey sites.
Concentration of NH3 was high from July to
November, while emission of NH3 was high
from June to September (summer) and low from December to March
(winter). Trend of NO2 concentration was
high in winter and low in summer, a similar tendency to that of
NOx emission. On the other hand, the trend
of HNO3 concentration was high in summer
and low in winter. There was no particular seasonal trend of SO2 concentration and SO2 emission
had also no seasonal variation but was constant.
Keywords: Emission inventory; Third-order mesh code; Passive method;
NH3; NO2; NOx;
HNO3; SO2』
1. Introduction
2. Methods
2.1. Emission inventory
2.2. Passive method
3. Results and discussion
3.1. Annual emission map
3.2. Monthly emission variation
3.3. Relation atmospheric gas concentration with its emission
inventory
3.4. Monthly variation at whole-year survey sites
4. Conclusions
Acknowledgements
References