Download Upper Green Winter Ozone Study

Upper Green River Basin Wyoming
Winter Ozone Study
WESTAR Oil and Gas Conference
September 12, 2007
Cara Keslar
Wyoming DEQ - Air Quality Division
Introduction
 Background
 Ozone Monitoring
Field Study Design
 Field Study Results
Jonah 12:00 2/27/06
Background
Hourly Average Ozone Concentrations
February 2005, Jonah
Study Periods
Slide compliments of NOAA
2005 & 2006 Top 5 8-hour ozone concentrations
Jonah
Date
ppm
02/03/05 0.098
02/26/05 0.089
Boulder
Date
ppm
02/20/05 0.089
02/03/05 0.081
Daniel South$
Date
ppm
07/08/05 0.070
07/07/05 0.067
01/24/05
02/04/05
02/27/05
0.078
0.076
0.075
02/04/05
02/24/05
02/19/05
0.080
0.080
0.079
07/22/05
07/11/05
07/03/05
0.066
0.066
0.064
02/27/06
02/25/06
05/02/06
0.093*
0.081*
0.071
04/21/06
06/18/06
05/02/06
0.081
0.079
0.076
02/25/06
05/02/06
04/21/06
0.083
0.076
0.075
06/11/06
07/15/06
0.070
0.070
06/01/06
08/18/06
0.073
0.072
02/27/06
06/18/06
0.075
0.073
* Less than 75% data completeness
$ Began operation in July 2005
Theories on Causes
 Monitoring error: Not Likely




Checked certifications
Additional 3rd party audits
Elevated concentrations at multiple monitors
Winter 2006 put Chemiluminescent ozone monitor at Jonah
to check for VOC interference and found none
 Stratospheric Intrusion: Not Likely

Tight inversion and stagnant conditions for several days
 Transport: Slight Possibility

Other areas had not reported high wintertime conditions
Theories on Causes (cont.)
 Locally Formed:
Most Likely




Precursors emitted
in area
Suspected tight
inversion
Stagnant
conditions
High Elevation,
sunny, snow cover
2005
AQD Response to
Ozone Events
 Concerns about elevated concentrations



Potential for NAAQS violation
Health effects on local public
More development planned in SW Wyoming
 Requested proposals for a special study



Ambient and Meteorological Field Study
Modeling Study
Emission Inventories
Ozone Monitoring Field
Study
Ozone Monitoring Field
Study
 2005 & 2006 meteorological evaluation – forecasting



High pressure aloft
Light surface winds
Snow cover


Stable boundary layer
UV reflectance
 Gather online data from other sources


Total columnar ozone
GOES temperature profiles
 Field Study - February and March 2007


Continuous Measurements
Intensive Operating Periods (IOP)
Continuous
Measurements
 Continued and enhanced
monitoring at Boulder,
Jonah, and Daniel South
 CastNet continued
collecting ozone data
 Airport operations
 Profiler Site
 Mesonet Meteorology
Intensive Operating Periods
(IOPs)
 Operational forecasts


Elevated ozone events likely
Trigger Intensive Operating Periods (IOPs)
 IOP Measurement Objectives

Determine structure of atmosphere during high ozone
events:





How shallow is the inversion?
What does the vertical ozone profile look like?
What differences exist between Jonah, Boulder, Daniel?
Determine spatial variability of ozone concentrations
around Upper Green River Basin
Determine VOC and Carbonyl concentrations
IOP
Measurements
 Tetheredsondes and
VOC/Carbonyl at
Boulder, Jonah and
Daniel South
 Rawin/ozonesondes at
Airport
 Mesonet Ozone
 Aircraft measurements
2007 Field Study Results
Jonah
Station and
surrounding
area
3/17/07
Station
Mean 500 mb Wind Speeds
Feb-Mar 2005, 2006
Feb-Mar 2007
Substantially stronger upper level winds during 2007 field study
Mean Surface Temperatures
Feb-Mar 2005, 2006
Feb-Mar 2007
Warmer temperatures during 2007 field study
ppb
Jonah 8-Hour O3
Consistently lower
O3 in 2007
March
Maximum Ozone Concentration
Ozone (ppb)
140
120
100
Boulder
Jonah
Daniel
80
60
40
20
0
Hourly Max
8-Hourly Max
2005-2006
Hourly Max
8-Hourly Max
2007
Aerial Measurements
17 March Morning Flight
NO titration and
elevated PM under
inversion
Haystack
Butte
17 March Afternoon Flight
- Uniform O3
- Low PM
- No inversion
Boulder
Rawinsonde/Ozonesonde
72 ppb
O3 layer
aloft
O3 depletion
below inversion
Inversion
Morning
Afternoon
No
Inversion
Ground-level Measurements
Hourly Ozone at Selected Sites
O3 at upwind
location
60
Ozone (ppb)
50
40
30
Ozone
depletion due
to NO titration
20
10
Cora
Jonah
Simpsons Gulch
0
0
2
4
6
8
10 12 14
Hour(MST)
16
18
20
22
UV Albedo
0.9
Albedo
UV Insolation
0.8
400
Daily Avg.
350
07:00 – 19:00 MST
0.7
Albedo
0.6
250
0.5
200
0.4
150
0.3
UV Insolation (W/m2)
300
2 March: Albedo = 0.81 (snow)
100
0.2
0.1
50
0.0
0
2/28
3/15
3/30
4/14
4/29
23 March: Albedo = 0.04 (bare
ground)
VOCs: Mean Concentration
ppbC
Total Identified
5000
4000
3000
2000
1000
0
Boulder
Daniel
Paraffins
ppbC
ppbC
3000
2000
1000
0
Boulder
Daniel
Jonah
Jonah
Olefins
40
30
20
10
0
Boulder
Daniel
Jonah
Median VOC Concentrations:
Top
Six
120
100
Boulder
Daniel
Jonah
60
40
20
ne
nt
a
nPe
ne
i-P
en
ta
an
ut
i-B
ta
Bu
n-
e
ne
e
an
op
Pr
ha
ne
0
Et
ppbV
80
et
h
yl
E
M 2- cyc th
et M lo en
hy e he e
l t thy xa
er lh n
t b ex e
C uty an
3- yclo l et e
M p h
2- eth ent er
2, Me ylh an
2- th e e
D y xa
im lh n
et ep e
hy ta
lb ne
n- uta
M
H ne
et
ex
hy
a
2- lcy To ne
M clo lue
et p n
2- hyl en e
M -1 tan
et he e
hy x
lp en
e
n- nta e
H n
ep e
Be tan
nz e
en
e
M
ppbV
Median VOC Concentrations:
Remainder
of
Top
21
8
7
6
5
4
3
2
1
0
Boulder
Daniel
Jonah
Carbonyl Analysis
12 Samples at Each Site
Not Detected
2,5Dimethylbenzaldehyde,
Hexaldehyde,
Isovaleraldehyde, m,o,pTolualdehyde,
Propionaldehyde,
Valeraldehyde,
Sometimes
Detected
Buteraldehyde
(roughly half of all
samples),
Crotonaldehyde (2
samples)
Detected in all
or nearly all
samples
Acetaldehyde, Acetone,
Benzaldehyde,
Formaldehyde
Formaldehyde
Max
9
Jonah
Boulder
Daniel
8
Mean
7
•Several formaldehyde
sources near Jonah (high
early morning
concentrations)
6
ppbV
5
4
3
Tentative Conclusions:
• Possibility of some
midday photochemical
production at Boulder
Min
2
•Need more sampling!
1
0
0400-0700
0900-1200
Time (MST)
1400-1700
Summary
 Weather conditions associated with high ozone
events in 2005-2006 did not occur during 2007


Warmer temperatures, lack of snow cover
Morning surface inversions did not persist
 Observed “background” O3 in 50 – 55 ppb range
 Increases in NOx and reduced O3 at Jonah
compared to 2005-2006

Need site downwind to observe results of O3 formation
 Need more information on VOC/carbonyl
Lessons Learned
 Difficult to forecast high O3 events
 Lack of reliability, and low humidities
limited usefulness of profilers
 Importance of local personnel to help with
troubleshooting equipment, downloading
data and coordinating logistics
Recommendations
for 2008 Field Study
 Start operations by mid-January
 Maintain wind & temperature obs at 8 mesonet sites
(equipment has been purchased)
 Allow for potentially more IOPs by limiting cost of
each






Reduce number of mesonet sites with O3
Eliminate tethersondes
Focus on aircraft for horizontal and vertical distributions
of ozone, PM, temperature
Simplify continuous upper air (SODAR or miniSODAR)
Use leftover ozone/rawinsondes
More VOC/carbonyl sampling
Questions
Cara Keslar
Field Study
Project Manager
307-777-8684
Darla Potter
Acting Modeling Study
Project Manager
307-777-7346