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.

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

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

AcknowledgmentsThis 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.

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. (SE-US), 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 FLEXPART-WRF models; for fire detection the Fire Locating And Modeling of Burning Emissions (FLAMBE).

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.

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.

Saint Louis, MO – STLHuntsville, AL – UAHIdabel, OK – IOKTallahassee, FL – FSUHouston, TX – ETXBoulder, CO – BCOSocorro, NM – SNM

Fig. 1

STL

UAH

FSU

IOK

ETX

BCO

SNM

Fig. 3: Median, IQR, and min/max range of O3 profiles from SLU data (28 launches).

Fig. 2: STL Ozonesonde Tropospheric profiles, ozone daily values are averaged vertically every 500m.

O3 ppb

NASA AURA’s OMI satellite retrievalsare validated using SEACIONS Data

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.

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.

A large ridge of high pressure exist over the SC-US during the week prior, and it remains quasi-permanent 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.

Three Case Studies With Elevated Ozone Over STL

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.

(B) 30-Aug-2013 (C) 12-Sep-2013

21 Aug 2013 30 Aug 2013 12 Sep 2013

(A) 21-Aug-2013

Cut-off Low Fire Plume Stagnant Ridge (Fire+STE) Plume Frontal passage STE Plume

1A

2A

1B

2B

1C

2C

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.

B) Transported Plume Ages

Fig. 7: Transport from FLAMBE emissions within the pbl (0-3500m) is combined with identified pyro-cb injections (> pbl+500m) inside FLEXPART-WRF runs.

CO (µg/cm

^-3)CO

Particle Age (days)

Hei

ght (

km)

Hei

ght (

km)

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) Biomass Burning CO Transport

SEACIONS Data can be found athttp://croc.gsfc.nasa.gov/seacions/

Relative Humidity (%)

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.

8/28 8/30

8/27

UAH 8/27 sonde

UAH 8/28 sonde

UAH 8/30 sonde

90+ ppb 4-7km 5-7km layer

cleaner air

During SEACIONS mid-level elevated O3 layers are captured by UAH O3 DIAL and Sondes

8/28 8/30

8/19 8/218/20 8/22

UAH 8/20 sonde

UAH 8/21 sonde

UAH 8/22 sonde

UAH 8/19 sonde

PBL height raises, pollution layer >4km

Summary

Table 1. Ozone Enhancement plume info.

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)).

12-Sep-13

30-Aug-13

21-Aug-13

P1

P2

P1

P2

P3

P1

Origin: UT/LS

Origin: UT/LS + Wildfire

Origin: Wildfire

Conclusions/Future Work