Utah Wintertime PM2.5 Modeling Utah Wintertime PM2.5 Modeling Lance Avey Utah Division of Air Quality
Jan 13, 2016
Utah Wintertime PM2.5 ModelingUtah Wintertime PM2.5 Modeling
Lance AveyUtah Division of Air Quality
http://www.airquality.utah.gov/
Ammonium Sulfate 9%
Organic Carbon 20% Ammonium Nitrate
58%
Other 5%
Elemental Carbon 5%
Dust 2%
PM2.5 Speciation
NOx + VOCs HNO3 (nitric acid)
HNO3 + NH3 NH4NO3 (particulate)
NAAQS for PM2.5
• EPA revised the NAAQS for PM2.5 in December of 2006
– 24-hr standard was lowered from 65 micrograms per cubic meter
(µg/m3) to 35 µg/m3
– Annual standard was retained at 15 µg/m3
– Retained the 24-hr standard for PM10 at 150 µg/m3
State Implementation Plan
• Basic Elements include:
– Modeled Attainment Demonstration (with chemistry)– Emissions Inventories– Emission Limits– Attainment Dates (2 – 7 years after SIP)
Retrospective Modeling
• Replicate the meteorological, emissions, and chemistry of past high PM2.5 episodes
• In the future, the same meteorology and chemistry will cause high PM2.5 episodes
• Future emissions will change – Population Growth, new technologies, cleaner vehicles
• Allows DAQ to evaluate how future changes in emissions (and control strategies) effect PM2.5
EmissionsPoint, Area, Mobile
• 36/12/4 km Horizontal Domain• 37 vertical layers
– 1st layer at ~ 12 meters
– 10 layers below 250 meters
– Initialization uses 12km-NAM Re-analysis
• Pleim-Xiu LSM & Surface Layer, ACM2 PBL• Simulations were ran in 5.5 day segments• Observational and Analysis Nudging
UDAQ Retrospective WRF
Modeling Domain
4km x 4km
WRF Output
2010 Jan 04 – Midnight Local Time
CMAQ Nitrate (ug/m3)
2010 Jan 04 – Midnight Local Time
Hawthorne
0
10
20
30
40
50
60
70
10-Jan 12-Jan 14-Jan 16-Jan 18-Jan 20-Jan 22-Jan
January 2007
24-h
r P
M2.
5 (u
g/m
3)
CMAQ Obs.
Hawthorne CMAQ PM2.5 Simulation Speciation
NO347%
NH416%
SO44%
OC12%
EC7%
OTHER14%
Hawthorne STN PM2.5 Observed Speciation
NO342%
NH416%
SO42%
OC21%
EC4%
OTHER15%
Hawthorne Monitor
Monitor Design Value (observations)
201
4 B
AU
Des
ign
Val
ue
201
9 B
AU
Des
ign
Val
ue
2014
Co
ntr
ol D
esig
n V
alu
e
201
9 C
on
tol D
esig
n V
alu
e
201
9 A
ttai
nm
ent
Des
ign
Val
ue
0
5
10
15
20
25
30
35
40
45
50
2008 2014 2019SLC-Ogden-Clearfield NAA Controling Monitor
PM
25 (
ug/m
3)
Future Year Modeling-Same Meteorology-Same Chemistry-Changes in Emissions