An Analysis of SEACIONS Ozonesonde St. Louis, MO. Site in August-September 2013:
Insight into the Influences of Wildfires and Strat-Trop Exchange on Midwest Regional Air Quality
Joseph L. Wilkins1, Gary A. Morris2, Jack Fishman1, Benjamin de Foy1 , Charles Graves1 , Mike Newchurch3, Shi Kuang3, Ed Hyer4, David Peterson4, and Anne M. Thompson5
1.Saint Louis University , 2.Valparaiso University3. U. of Alabama-Huntsville 4. Naval research lab 5. NASA GSFC / Penn State
Saint Louis, MO
Huntsville, AL
Idabel, OK
Tallahassee, FL
Houston, TX
Boulder, CO
Socorro, NM
Fig. 1
SNM
– STL
– UAH
– IOK
– FSU
– ETX
– BCO
– SNM
STL
21 Aug 2013
Cut-off Low  Fire Plume
ETX
Fig. 1: FLEXPART-WRF model domain; rectangles mark the grids resolution, D1 is
12km and D2 is 4km. Also overlaid is a map of total smoke emissions mass (1 Gg =
10^9g) from FLAMBE database during 08 Aug to 22 Sept 2013. The emissions are
gridded per 0.25° cell with a minimum threshold of 2000kg. The triangle represent
Saint Louis, MO, with the rest of the SEACIONS location being marked by circles.
NASA AURA’s OMI
satellite retrievals
are validated using
SEACIONS Data
1C
1B
1A
8/19
UAH 8/27
sonde
2B
2A
2C
8/27
Relative Humidity (%)
Fig. 5: Test cases with varying meteorological situations driving ozone enhancements over SE-US. RH<30%
(shaded), pressure (black), and Potential Vorticity (blue). 1) 500hPa map 2) Cross section of 90° W meridian.
Evidence of a cut-off low presents
itself on 0817-00z at 500hPa over
central Missouri. The low remains
nearly stationary until 0819-00z, at
which time the trough fills in and
moves eastward. Due to the nature
of the quasi-stationary system, the
flow of air was expected to flow
along the contours rather cleanly
over the time periods. Persistent
flow allowed for fire plumes out
west to propagate over the SE-US.
(B) 30-Aug-2013
FLEXPART-WRF simulations are
driven by FLAMBE emissions within
the model domain (shown in Fig. 1),
Trajectory overpasses are binned
inside a 2.5°x 2.5° grid box over STL.
A large scale trough allowing for
Stratospheric air to extend down
slowly propagating eastward from
Idaho on 0909-00z. By 0910-12z the
system reaches the Dakotas and
continues east, moving over
Minnesota by 0911-12z. The system
then remains slightly north of STL and
stays nearly stationary. As the system
sits north of STL it then strengthens
and on 0912-12z it becomes fairly
prominent at 300hPa down to the
850hPa level.
This work was supported in part from NASA Grant NNX11AJ63G
to Saint Louis University through its AQAST Program. A special
thanks to data providers: FLAMBE Provided by: Ed Hyer, and
UAH for the O3 Lidar, OMI overpass data from Michael Yan.
8/22
8/30
UAH 8/28
sonde
UAH 8/30
sonde
5-7km layer
cleaner air
8/30
8/28
21-Aug-13
P2
P1
Origin: UT/LS + Wildfire
30-Aug-13
P3
P2
P1
Fig. 7: Transport from FLAMBE emissions within the
pbl (0-3500m) is combined with identified pyro-cb
injections (> pbl+500m) inside FLEXPART-WRF runs.
A) Biomass Burning CO Transport
Origin: UT/LS
12-Sep-13
P1
Height (km)
CO Particle Age (days)
Acknowledgments
Fig 6: FLAMBE emissions mass/time are converted to particle
numbers for FLEXPART-WRF input. Each particle = 500kg of mass.
Locations emitting <500kg only emit a single particle. Red lines are
for the Idaho Beaver Creek wildfire’s significant emissions start
(solid) and end (dotted). Blue lines are for the California Rim Fire.
8/28
Origin: Wildfire
O3 ppb
SEACIONS Data can be found at
http://croc.gsfc.nasa.gov/seacions/
Fig. 4: Daily OMI retrievals at ~18Z are
compared with estimated total sonde
column O3 using McPeters et al, 2007.
Sonde burst heights <26 km are excluded
and days with shortwave disturbances.
8/21
Table 1. Ozone Enhancement plume info.
B) Transported Plume Ages
Fig. 2: STL Ozonesonde Tropospheric
profiles, ozone daily values are
averaged vertically every 500m.
UAH 8/22
sonde
Fig. 8: UAH O3 DIAL, O3 Lidar measurement at Huntsville, AL summer 2013 during the SEACIONS mission.
Enhanced layers observed: 19-21 Aug 4-6km, 22 Aug 4-5 km, 27-28 Aug. ~5 km, and 30 Aug. 5-8 km.
(C) 12-Sep-2013
A large ridge of high pressure exist over the SCUS during the week prior, and it remains quasipermanent as it becomes well established over
Missouri on 0825-00z. The high pressure remains
stagnant reaching its max strength at 0826-06z
until a shortwave trough or weak front moves in
082912z, spotted at 500hPa. The near surface
portion of the shortwave reaches Eastern N.
Dakota 0829-18z as the trough extends down to
Oklahoma where it penetrates deeper into the
ridge. The shortwave caused the ridge to move
westward as it moved eastward. The flow within
the shortwave was relatively weak but still
strong enough to generate a small intrusion or
trop fold to accompany air from out west.
8/20
90+ ppb 47km
CO (µg/cm^-3)
Fig. 3: Median, IQR, and
min/max range of O3 profiles
from SLU data (28 launches).
UAH 8/21
sonde
UAH 8/20
sonde
PBL height
raises, pollution
layer >4km
(A) 21-Aug-2013
FSU
12 Sep 2013
Frontal passage STE Plume
UAH 8/19
sonde
UAH
IOK
30 Aug 2013
Stagnant Ridge  (Fire+STE) Plume
Height (km)
o The SouthEast American Consortium for Intensive Ozone Network Study
(SEACIONS) mission consisted of concurrent ozonesonde launches from
St. Louis, MO and six other locations across the South Eastern U.S. (SEUS), between Aug. 8 and Sep. 23 2013 (see Fig. 1).
o Primary science objectives: 1. Investigate convective and wave signatures
in ozone (O3) profiles 2. Further explore the interaction of fire generated
pollution and pyro-cumulonimbus (pyro-cbs) convective transport.
o During SEACIONS several sources of elevated O3 were detected. Three test
cases were chosen to display transport influences from wildfires out west,
SE-US agricultural fires, and subsiding air from the Upper Troposphere
and Lower Stratosphere (UT/LS).
o To interpret our ozonesonde observations, we used an O3 Lidar from
Huntsville, AL; trajectory calculations from the NASA GSFC, and FLEXPARTWRF models; for fire detection the Fire Locating And Modeling of Burning
Emissions (FLAMBE).
BCO
During SEACIONS mid-level elevated O3 layers
are captured by UAH O3 DIAL and Sondes
Three Case Studies With Elevated Ozone Over STL
Summary
Fig. 9: Ozonesonde O3 ppb (black) and RH % (green), GSFC-Model Potential Vorticity 10^-6 pvu (blue),
and FLEXPART-WRF CO BB(µg/cm^-3) normalized (shaded pbl (gray), pyro-cb (pink)).
Conclusions/Future Work
o SEAC4RS data allowed for identification of ~42 pyro-cb producing considerable O3 plumes
downwind over SE-US. Without the inclusion of pyro-cbs models will incorrectly place or
could miss pollution transport patterns.
o For satellite validation using ozonesondes, the climatology for burst height corrections
method updated by McPeters et al 2007 allows for more accurate results than pervious.
However comparisons were improved by 37% by retrofitting regional meteorological
influences (shortwaves, STE, convection, and other processes effecting the UT/LS)
producing outliers on a year to year basis.
o Using SEAC4RS/SEACIONS measurements we are able to further confirm a reoccurring
layer of ozone generated every summer during a high pressure system. Initially believed
to be primarily from lightening Nox, our data shows that there is more to the story as
little lightening was present during this experiment and we still captured the same layer.
o Future Work: Infer photochemical production of ozone rates based on FLEXPART-WRF CO
trajectories. Create a synthetic test of wildfire emissions to characterize and investigate
pyro-cb transport effects on ozone production.