Emission Control Impact on Ozone Levels
from mobile and point sources in southern China
Ying Li, Alexis Lau, Jimmy Fung
1
Exceedance seen at all sites – even urban ones
2
Emission update
and
Model verification
3
MODELING SYSTEM (recently update)
Meteorological
MM5v3.6.3
Air Quality
Model
CAMx 5.10
Emission
Processor
SMOKE 2.4
+
Air Quality
Model
CMAQ 4.6
Gridded Emission
INTEX-B
4
1795.5
1579.5
Coordinate system projection parameters for the PATH
Modelling system.
1363.5
1147.5
27km
931.5
715.5
Parameter
499.5
Value
Projection
Lambert-Conformal
Alpha
15 degrees North Latitude
Beta
40 degrees North Latitude
x center
114 degrees East Longitude
y center
28.5 degrees North Latitude
283.5
67.5
-148.5
-364.5
-580.5
-796.5
-1012.5
-1228.5
-1444.5
-1660.5
-1876.5
-2403
-1971
-1539
-1107
-675
-243
189
621
1053
1485
1917
2349
-319.5
-430.5
-373.5
-457.5
-427.5
-484.5
-481.5
-511.5
-535.5
-589.5
-538.5
9km
-565.5
-592.5
-643.5
-646.5
-751.5
-673.5
-805.5
-700.5
-859.5
-727.5
-913.5
-967.5
-522 -468 -414 -360 -306 -252 -198 -144 -90
3km
-619.5
-697.5
-36
18
72
126
180
234
288
342
-754.5
-291 -264 -237 -210 -183 -156 -129 -102 -75
5
-48
-21
6
33
60
87
114 141
INTEX-B D1
6
Spatial allocation (srg) of emissions 1
New area
New mobile
Old area
Old mobile
7
Spatial allocation (srg) of emissions 2
New marine
New SZ area
Old marine
Old SZ area
8
Station:
Lau Fau Shan
9
Luhu site of GZ
Donghu site of Jiangmen
Simulation of
ozone maxima
is improved
Simulation of
ozone maxima
is improved
10
Temporal trend of OzoneNOx-VOC sensitivity
11
O3 variation caused by reducing
30% NOx emission of all emission source
8 AM
VOC
limited
O3_perturbation case - O3_base case
>0 (red)  VOC-sensitive
<0 (blue)  NOx-sensitive
12
O3 variation caused by reducing
30% NOx emission of all emission source
2 PM
VOC
NOX
limited
O3_perturbation case - O3_base case
>0 (red)  VOC-sensitive
<0 (blue)  NOx-sensitive
13
Base case: O3 concentration at 2PM
14
Feasible ozone control strategies,
and evaluation
Mobile : NOx & VOC
Point : NOx
Area : VOC
15
交通源及点源控制措施及减排效率
减排措施
a. 推行国Ⅲ标准
适合范围
汽油 汽油 汽油 柴油 柴油 柴油 摩托
小客 小货 大客 小货 大客 大货 车
√
b. 机动车限行
√
√
√
√
√
√
√
√
√
√
c. 推行国Ⅳ标准
√
√
√
√
√
√
其它
√
√
√
√
√
√
√
√
目标污染物
可削减%
NOx ＆ VOC
11.1%
NOx ＆VOC
5.9%
NOx ＆VOC
12.9%
3～4%
～30%
总合
适用范围
减排措施
目标污染物
可削减%
NOx
20-60%
大电厂
小电厂
工业源
低氮燃烧
√
√
√
SNCR
√
√
NOx
40%
SCR
√
√
NOx
80%
16
Design of Control Scenarios
(1) Reducing both VOC and NOx emissions of PRD
mobile source by 50%;
(2) Reducing VOC emissions of PRD mobile and
area source by 50% (less feasible);
(3) Reducing NOx emission from point source by
50%;
(4) Reducing NOx emission from point source by
85%;
(5) case 1 + case 3
17
What’s the mobile control
impact on ozone
concentration?
18
GZ city averaged effect
GZ luhu site
FS city averaged effect
FS huijingcheng site
19
What’s the point source
control impact on ozone
concentration?
20
The O3 time series of NOx/VOCs zero
impact of GZ city average
21
Autumn case :O3 and O3 variation by reducing 50%
NOx from point source
Color:
Base case
Contour:
black: O3 decr.
white: O3 incr
Color:
with NOX control
Contour:
black: O3 decr.
white: O3 incr
22
Autumn case :O3 and O3 variation by reducing 50%
NOx from point source
Color:
Base case
Contour:
black: O3 decr.
white: O3 incr
Color:
with NOX control
Contour:
black: O3 decr.
white: O3 incr
23
Summer case :O3 and O3 variation by reducing 50%
NOx from point source
Color:
Base case
Contour:
black: O3 decr.
white: O3 incr
Color:
with NOX control
Contour:
black: O3 decr.
white: O3 incr
24
O3 Frequency distribution of base case and 4 NOx reduction cases
25
Comparison of control strategies
Case
Source category
Emission type
and reduction
Control
feasibility
D3 total O3 variation
(ppb)
1
PRD&HK On-road mobile
NOx 50%
VOC 50%
high
34820
2
PRD&HK On-road
mobile, area
VOC 50%
low
16740
3
PRD&HK Point source
NOx 50%
high
19470
4
PRD&HK Point source
NOx 85%
high
43430
5
PRD&HK Point source,
on-road mobile
NOx(50%pt 50%mv)
VOC 50%mv
high
83070
•VOC control almost always lead to ozone decrease
•NOx control lead to ozone increase at the locations with low concentration,
and decrease at locations with high concentration.
26
Summary of feasible O3 Control strategy priority of the
autumn case
Reduce PRD 50% traffic is the most effective control strategy
Reduce PRD 50% VOCs from traffic and area has similar
effect in GZ
The large point sources are not the major sources for these
ozone increased, but lead to NOx-titration effect.
The contribution from these large point sources is notable in
the areas further downwind.
The sources that generate the elevated ozone in the upwind
areas to the point sources and the point sources that positively
contribute to the ozone formation should be considered as the
real contributing sources for the highest ozone concentration.
27