Figure 9. Vertical tropospheric profiles over St. Louis at ~18:30 to 19:30 UTC for selected test cases 21 August 2013 and 30 August 2013. Labels P1 to P6 correspond to plume information in Table 3. Ozone measured from the ozonesonde in ppb are shown as a black line. Panel (a) and (d), the green line RH %. Panel (b) and (e), the blue line represents the GEOS-5 modeled Potential Vorticity 106 PVU. Panel (c) and (f), the FLEXPART-WRF modeled CO biomass burning g cm-3, for each simulation the PYRO simulation is red, and BASELINE simulation in gray. Refer to Figure 2 for corresponding ozonesonde curtain plots.
Three ozone enhanced layers are visible on 21 August (Table 3, Figure 9). None of these enhancements are deemed of stratospheric origins, as there was no significant PVU present in these layers. Plume P3 at 11 km was initially considered to be a stratospheric intrusion related but are ruled out as the NARR data and sonde thermal tropopause indicate that the tropopause was lowered (15 km to ~9 km) possibly by wave breaking from the cut-off low. The lower- and upper-middle tropospheric ozone enhancements at P1 (2 to 5.5 km) and P2 (7 to 9 km), respectively, are determined to be of biomass burning origin. The lower-tropospheric plume P1 was determined to be from the Idaho Beaver Creek plume ~6 days earlier. The upper-middle tropospheric plume P2 originated 2 days prior from high-altitude injection plumes from the Yellowstone National Park Emigrant cluster fires. The contribution of 21 August tropospheric ozone layers from biomass burning was 10 to 25 ppbv. The pyroCb from the Idaho Pony Elk Fire (16 Aug at 23:41 UTC) reached the St. Louis area; But, the polluted air remained in the lower stratospheric air and did not mix with the lower layers. The incorporation of the high-altitude injection plumes allowed for the two middle- and upper- tropospheric polluted plumes to be characterized which contributed ~15 to 30% to layers in the total ozone column. This upper level pollution was later advected down to the surface and contributed to the exceedance on the 23 August.
4.5.2. 25-30 August 2013: Evidence of stratospheric air mixing with aged biomass burning during anticyclonic flow
The meteorological map provided in Figure 6d-f indicates aged biomass burning transported into a stratospheric intrusion by a high pressure system that became well-established over Missouri 25 August 00:00 UTC. The high pressure system began developing a week prior over the southcentral U.S. The high remained quasi-permanent as it sat over Missouri reaching its maximum strength on 26 August 06:00 UTC until a mid-level (500 hPa) shortwave trough moved into the area on 29 August 12:00 UTC moving the system eastward. The near surface reflection of the shortwave reaches Eastern North Dakota 29 August 18:00 UTC as the trough extends south to Oklahoma where it penetrates deeper into the ridge. Figure 7b and 7d presents a cross section and plane view of the resulting high. Due to the high pressure system the trajectory analysis indicated that smoke flowed from various fire locations in additional to stratospheric intrusion impacts to the St. Louis area (see Figure 8). Figure 9d-f depicts the vertical ozone and meteorological profiles representative of this time period (30 August). Further evidence of this trough effects on elevated ozone aloft in the sonde measurements (see Figure 2) remained until 30 August 18:00 UTC (Figure 9d-f). Thereafter a shortwave passes the area slightly to the east and cleared out the excess ozone.
Three ozone enhanced layers are present during the high pressure event as evident on 30 August (Table 3, P4 to P6). Stratospheric air descended into the middle troposphere ~500 hPa on two occasions during this time period (28 Aug and 30 Aug) from shortwaves (Figure 7d). Stratospheric impacts are indicated at ~7 to 9 km and >12 km layers with high PVU values and low RH values (Figure 9d-f, P5 and P6). NARR PVU analysis provided further proof that these are in fact stratospheric in origin. Figure 7d depicts lowering dry stratospheric air and ascending moist tropospheric air. The near surface plume (0 to 3.5 km) was traced back to southeastern agricultural fires ~5 days prior (see Figure 8), indicating a likely recirculation of air by the high pressure system. The middle-tropospheric plume P5 was determined to be from an unknown source, potentially a recirculation of summertime ozone precursors (Cooper et al., 2006, 2007). Evidence of this layer is present in previous soundings for the week 25-29 August where all sondes show a single well-defined plume at ∼5 to 9 km. The GEOS-5 and NARR potential vorticity also give no indication of what the cause for this layer is. Our hypothesis is supported by the vertical wind profiles for the week being relatively stagnant— the ozonesonde launched that day landed within 50 m of the launch site — signifying air circulation over St. Louis for the entire week increasing photochemical effects. An alternative theory is that wind shear caused the layer and it’s a part of the larger plume above. The layer between the unknown plume and above (~6 to 8 km) is a layer of moist and clean air (see Figure 7d). The upper-tropospheric layer plume P6 is a combination of both a biomass burning plume and a stratospheric intrusion air mass. The lower half of the plume P6 (8 to 10 km) is dominated by stratospheric air, while the above portion of P6 (10 to 12 km) is primarily biomass burning. There is another layer of clean air above prior to reaching the tropopause. The upper-tropospheric plume P6 originated 5 days prior from high-altitude injection plumes from the California Rim Fire (25 August). The contribution of 30 August tropospheric ozone layers from Biomass burning was 10 to 80 ppbv and stratospheric air masses contributed 10 to 40 ppbv. The incorporation of high-altitude smoke injection allowed for the two mid- and upper- tropospheric polluted plumes to be characterized which contributed ~15 to 60% to layers in the total ozone column.
5 Summary and Conclusions
By incorporating balloon-borne ozonesonde observations with models, this study has quantitatively examined sources for tropospheric ozone enhancements due to Non-Controllable Ozone Sources (NCOS). In particular, the pollution impacts from stratospheric intrusions and biomass burning contributions to background tropospheric and surface ozone levels in the Midwest United States were characterized. Additionally, emphasis is placed on partitioning the contribution from western U.S. fires, central U.S. fires, and other areas to St. Louis background ozone. A chemical transport model and trajectory model were run to quantify source contribution to ozone in St. Louis, Missouri. For the region and time period of this study, 10 to 15% of the ozone enhancements stems from a stratospheric airmass contribution and 15 to 30% from biomass burning. These NCOS contributions and ozonesonde profiles can be considered as baseline ranges for the Midwest U.S. area if direct ozone measurements (sondes, airplane, ground-based) are not available. Considering U.S. fires only, 70% of the biomass burning plumes originated from the western parts of the U.S. and only 3% came from the local central U.S. emissions. Moreover, it was demonstrated that a redistribution of the biomass burning emissions injection height, with part of the emissions above the boundary layer led to a reduction of model predicted surface ozone.
In agreement with earlier studies (e.g., Fishman et al., 2014), this study has identified a generally increasing relationship between background ozone and transported pollution. We followed the definition of background ozone described in Jaffe et al. (2018) as NCOS such as lingering biomass burning and long-range transported international sources. The major contributions below 3 km were from the central U.S. fires. While 80 to 90% of the high-altitude injection smoke (above 3.5 km) originated in the western U.S. During this campaign period only 5 to 10% of the biomass burning emissions reaching St. Louis originated from the southeast and other regions.
This study identified that biomass burning plumes in the western U.S. can have impacts on the daily atmospheric ozone column in the Midwest (10 to 80 ppbv of ozone) at a greater frequency and intensity than stratospheric intrusion (10 to 25 ppbv of ozone). We show the background ozone to be 55 ppbv, which was near the 30 to 50 ppbv range mentioned in Jaffe et al. (2018) which is typical for the U.S. We identified a relationship between smoke plume age and ozone enhancement where the high-altitude injection smoke plumes above 3.5 km generally were associated with higher amounts of CO concentrations but fresher smoke regarding ozone levels. In addition, we recognized that the high-altitude smoke had a higher tendency to mix with stratospheric intrusions, which together doubled the ozone enhancement in the tropospheric column.
An investigation of several individual smoke plumes has shown the importance of incorporating high-altitude smoke injection in model simulations in addition to ensuring that accurate biomass burning locations and temporal allocation of intensity are included in model emissions. Up to 60% of the smoke plume lies above 3.5 km, and this needs to be simulated as it can later be mixed down to the surface and lead to ozone exceedances days later. In addition, it was shown that the incorporation of satellite-based detections of high-altitude smoke injection (e.g., pyroCb activity, Peterson et al., 2014, 2017a,b) can be helpful for improve modeling results and explain ozone enhancements aloft and at the surface.
The individual cases were selected because they are associated with common meteorological situations in the Midwest leading to ozone exceedances. Evidence from the first case where biomass burning is advected by a cutoff low is an example of a common flow pattern that transports air masses from the west. Summertime occurrences of this synoptic situation in conjunction with large wildfires in the western U.S. can lead to increases in ozone in the Midwest of 10 to 80 ppbv or greater. In the second case a stratospheric air mass was shown to mix with an aged wildfire plume during anticyclonic flow, a pattern that was previously found to occur 40% of the time for the southcentral U.S. (Texas and the Gulf of Mexico area, Brioude et al., 2007). Additionally, the test cases showed that the surface impacts were connected to mechanisms causing air parcels to move downward (e.g. shortwave on 30 August). Likewise, strong vertical motion was evident in bringing simulated air within the boundary to the middle and upper portions of the troposphere.
While the results in this study highlight that Non-Controllable Ozone Sources can contribute significantly to local tropospheric ozone in the Midwest, future studies must combine satellite data and model integration techniques with meteorological information for a longer time period, both within and outside the Midwest to better characterize NCOS contribution to U.S. ozone. Good examples of how an air quality model could be used to assess NCOS has been shown in Baker et al. (2016, 2018). More specifically, Baker et al. (2016, 2018) address the question of regional-scale pyrogenic ozone sources. In particular, Baker et al. (2018) investigated the Rim Fire, using non-sonde data, which occurred during our study period with a photochemical model and their findings were similar to ours. Furthermore, as shown by individual plume cases and several earlier studies (e.g. Morris et al., 2006; Brioude et al., 2007; Jaffe, 2011; Lin et al., 2012; Hess and Zbinden, 2013), high-altitude smoke injection from a fire can lead to long distance transport depending on weather conditions and hence impact surface ozone and NAAQS attainment. Plume rise and plume injection heights are a key source of uncertainty (Paugam et al., 2016), which can be reduced considerably using plume height information from remote sensing tools (e.g. Peterson et al., 2017a,b; Val Martin et al., 2018). Improved modeling techniques will be required to better characterize biomass burning transport and hence better simulate long range impacts and the possibility of unhealthy surface concentrations far from the biomass burning sources.
Acknowledgments
The authors would like to thank the SEAC4RS and SEACIONS team members who gave input and guidance. A special thanks to Saint Louis University student participants in ozonesonde launches, Tim Barbeau, William Iwasko, Jackie Ringhausen, Patrick Walsh, and Jason Welsh. We also like to thank our Valparaiso University ozonesonde launch trainers Alex Kotsakis and Mark Spychala. We would also like to thank Dr. Jacky Rosati-Rowe at the U.S. EPA for editorial contributions. The data sets used in this work are publicly accessible and archived at https://tropo.gsfc.nasa.gov/seacions/ (ozonesonde data and trajectories) and https://www.nasa.gov/mission_pages/seac4rs/index.html (mission data e.g., fire emissions and flight information). This work was supported in part from NASA Grant NNX11AJ63G to Saint Louis University through its AQAST Program. D. Peterson was supported by the NASA New Investigator Program 80HQTR18T0073.
References
Baker, K. R., Woody, M. C., Tonnesen, G. S., Hutzell, W., Pye, H. O. T., Beaver, M. R., Pouliot, G., & Pierce, T. (2016). Contribution of regional-scale fire events to ozone and PM2.5 air quality estimated by photochemical modeling approaches. Atmos. Environ. , 140 , 539-554. doi:10.1016/j.atmosenv.2016.06.032
Baker, K. R., Woody, M. C., Valin, L., Szykman, J., Yates, E., Iraci, L., Choi, H., Soja, A., Koplitz, S., & Zhou, L. (2018). Photochemical model evaluation of 2013 California wild fire air quality impacts using surface, aircraft, and satellite data. Sci. Total Environ.,637 , 1137–1149.
Brioude, J., Arnold, D., Stohl, A., Cassiani, M., Morton, D., Seibert, P., et al. (2013). The Lagrangian particle dispersion model FLEXPART-WRF version 3.1. Geosci. Model Dev. , 6 (6), 1889-1904. doi: 10.5194/gmd-6-1889-2013
Brioude, J., Cooper, O. R., Trainer, M., Ryerson, T., Holloway, J. S., Baynard, T., et al. (2007). Mixing between a stratospheric intrusion and a biomass burning plume. Atmos. Chem. and Phys., (7), 4229-4235.
Colarco, P. R. (2004). Transport of smoke from Canadian forest fires to the surface near Washington, D.C.: Injection height, entrainment, and optical properties. J. Geophys. Res. , 109 (D6). doi: 10.1029/2003jd004248.
Cooper, O. R., Langford, A. O., Parrish, D. D., & Fahey, D. W. (2015). Challenges of a lowered US ozone standard. Science, 348 , 1096–1097.
Cooper, O. R., Stohl, A., Trainer, M., Thompson, A. M., Witte, J. C., Oltmans, S. J., et al. (2006). Large upper tropospheric ozone enhancements above midlatitude North America during summer: In situ evidence from the IONS and MOZAIC ozone measurement network. J. Geophys. Res. , 111 (D24). doi: 10.1029/2006jd007306
Cooper, O. R., Trainer, M., Thompson, A. M., Oltmans, S. J., Tarasick, D. W., Witte, J. C., et al. (2007). Evidence for a recurring eastern North America upper tropospheric ozone maximum during summer. J. Geophys. Res. , 112 (D23). doi: 10.1029/2007jd008710
Granier, C., Bessagnet, B., Bond, T., D’Angiola, A., van der Gon, H. D., Frost, G. J., et al. (2011). Evolution of anthropogenic and biomass burning emissions of air pollutants at global and regional scales during the 1980–2010 period. Climatic Change , 109 , 163-190. doi:10.1007/s10584-011-0154-1
Hess, P. G. & Zbinden, R. (2013) Stratospheric impact on tropospheric ozone variability and trends: 1990-2009. Atmos. Chem. Phys. ,13 , 649–674.
Hurst, D. F., Hall, E. G., Jordan, A. F., Miloshevich, L. M., Whiteman, D. N., Leblanc, T., et al. (2011). Comparisons of temperature, pressure and humidity measurements by balloon-borne radiosondes and frost point hygrometers during MOHAVE-2009. Atmos. Meas. Tech. , 4 , 2777–2793. doi:10.5194/amt-4-2777-2011
Davison, P. S. (2004). Estimating the direct radiative forcing due to haze from the 1997 forest fires in Indonesia. J. Geophys. Res. ,109 (D10). doi: 10.1029/2003jd004264
de Foy, B., Wilkins, J. L., Lu, Z., Streets, D. G., & Duncan, B. N. (2014). Model evaluation of methods for estimating surface emissions and chemical lifetimes from satellite data. Atmos. Environ. ,98 , 66-77. doi: 10.1016/j.atmosenv.2014.08.051
Fann, N., Alman, B., Broome, R. A., Morgan, G. G., Johnston, F. H., Pouliot, G., & Rappold, A. G. (2018). The health impacts and economic value of wildland fire episodes in the US: 2008–2012. Sci. Total Environ., 610 , 802-809. doi: 10.1016/j.scitotenv.2017.08.024
Fann, N., Fulcher, C.M., & Baker, K. (2013). The recent and future health burden of air pollution apportioned across U.S. Sectors.Environ. Sci. Technol. , 47 , 3580-9. doi: 10.1021/es304831q
Ferek, R. J., Reid, J. S., Hobbs, P. V., Blake, D. R., & Liousse, C. (1998). Emission factors of hydrocarbons, halocarbons, trace gases and particles from biomass burning in Brazil. J. Geophys. Res. ,103 (D24), 32107. doi: 10.1029/98jd00692
Fishman, J., Belina, K. M., & Encarnación, C. H. (2014). The St. Louis Ozone Gardens: Visualizing the Impact of a Changing Atmosphere.Bull. Amer. Meteor. Soc. , 95 , 1171-1176.
Fromm, M., et al. (2010). The untold story of pyrocumulonimbus.Bulletin of the American Meteorological Society , 91, 1193-1209.
Fromm, M., D. Peterson, & Di Girolamo, L. (2019). The Primary Convective Pathway for Observed Wildfire Emissions in the Upper Troposphere and Lower Stratosphere: A Targeted Reinterpretation.J. Geophys. Res. Atmos. , n/a.
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood, R. B., & Pfister, L. (1995). Stratosphere-troposphere exchange. Rev. Geophys., 33 (4), 403. doi: 10.1029/95rg02097
Jaffe, D. (2011) Relationship between surface and free tropospheric ozone in the Western U.S. Environ. Sci. Technol. , 45 , 432–438.
Jaffe, D. A., Cooper, O. R., Fiore A. M., Henderson, B. H., Tonnesen, G. S., Russell, A. G., et al. (2018). Scientific assessment of background ozone over the U.S.: Implications for air quality management.Elem. Sci. Anth. , 6 (56). doi: https://doi.org/10.1525/elementa.309
Jaffe, D. A., & Wigder, N. L. (2012). Ozone production from wildfires: A critical review. Atmos Environ. , 51 , 1-10. doi: 10.1016/j.atmosenv.2011.11.063
Jaffe, D. A., Wigder, N., Downey, N., Pfister, G., Boynard, A., & Reid, S. B. (2013). Impact of wildfires on ozone exceptional events in the western US. Environ. Sci. Technol. , 47 , 11065–11072.
Kley, D., Crutzen, P. J., Smit, H. G. J., Vömel, H., Oltmans, S. J., Grassl, H., & Ramanathan, V. (1996). Observations of near-zero ozone concentrations over the convective Pacific: Effects on air chemistry.Science , 274 , 230–233. https://doi.org/10.1126/science.274.5285.230.
Komhyr, W. D., Barnes, R. A., Brothers, G. B., Lathrop, J. A., & Opperman, D. P. (1995). Electrochemical concentration cell ozonesonde performance evaluation during STOIC 1989. J. Geophys. Res.,100 (D5), 9321-9244.
Komhyr, W. D., Oltmans, S., & Grass, R. D. (1986). Atmospheric Ozone at South Pole, Antarctica, in 1986. J. Geophys. Res., 93 (D5), 5167-5184. Doi:10.1029/JD093iD05p05167
Kuang, S., Newchurch, M. J., Burris, J., Wang, L., Knupp, K., & Huang, G. (2012). Stratosphere-to-troposphere transport revealed by ground-based lidar and ozonesonde at a midlatitude site. J. Geophys. Res.-Atmos. , 117 (D18), n/a-n/a. doi: 10.1029/2012jd017695
Lahoz, W. A., Errera, Q., Swinbank, R., & Fonteyn, D. (2007), Data assimilation of stratospheric constituents: A review, Atmos. Chem. Phys. , 7 , 5745–5773. doi:10.5194/acp-7-5745-2007.
Lal, S., Venkataramani, S., Chandra, N., Cooper, O.R., Brioude, J., & Naja, M. (2014) Transport effects on the vertical distribution of tropospheric ozone over western India. J. Geophys. Res. Atmos., 119 (16), 10012–10026. DOI: https://doi. org/10.1002/2014jd021854
Langford, A. O., Aikin, K. C., Eubank, C. S. & Williams, E. J. (2009). Stratospheric contribution to high surface ozone in Colorado during springtime. Geophys. Res. Lett. , 36 , L12801.
Langford, A. O., Alvarez, R. J., Brioude, J., Evan, S., Iraci, L. T., Kirgis, G., et al. (2018). Coordi­nated profiling of stratospheric intrusions and trans­ported pollution by the Tropospheric Ozone Lidar Network (TOLNet) and NASA Alpha Jet experiment (AJAX): Observations and comparison to HYSPLIT, RAQMS, and FLEXPART. Atmos. Environ. ,174 , 1–14. DOI: https://doi.org/10.1016/j. atmosenv.2017.11.031
Langford, A. O., Senff, C. J., Alvarez, R. J., Brioude, J., Cooper, O. R., Holloway, J. S., et al. (2015). An overview of the 2013 Las Vegas Ozone Study (LVOS): Impact of stratospheric intrusions and long-range transport on surface air quality. Atmos. Environ., 109 , 305–322. DOI: https:// doi.org/10.1016/j.atmosenv.2014.08.040
Larkin, N. K., Raffuse, S. M., & Strand, T. M. (2014). Wildland fire emissions, carbon, and climate: US emissions inventories. For. Ecol. Manag. , 317, 61–69. doi:10.1016/J.FORECO.2013.09.012
Li, K., Jacob, D.J., Liao, H., Shen, L., Zhang, Q., & Bates, K.H. (2019). Anthropogenic drivers of 2013-2017 trends in summer surface ozone in China. Proceedings of the National Academy of Sciences ,116 (2), 422–427. https://doi.org/10.1073/pnas.1812168116
Lin, M., Fiore, A. M., Horowitz, L. W., Langford, A. O., Oltmans, S. J., Tarasick, D., & Rieder, H. E. (2015) Climate variability modulates western US ozone air quality in spring via deep stratospheric intrusions. Nature Comm. , 6 , 7105, doi:10.1038/ncomms8105.
Liousse, C., Penner, J. E., Chuang, C., Walton, J. J., Eddleman, H., & Cachier, H. (1996). A global three-dimensional model study of carbonaceous aerosols. J. Geophys. Res., 101 (D14), 19411. doi: 10.1029/95jd03426
Liu, J. C., Pereira, G., Uhl, S. A., Bravo, M. A. & Bell, M. L. (2015). A systematic review of the physical health impacts from non-occupational exposure to wildfire smoke. Environ. Res. , 136 , 120–132. https://doi.org/10.1016/j.envres.2014.10.015
Liu, J. C., Mickley, L. J., Sulprizio, M. P., Yue, X., Peng, R. D., Dominici, F. & Bell M. L. (2016). Future respiratory hospital admissions from wildfire smoke under climate change in the Western US.Environ. Res. Lett. , 11 (10.1088), 1748-9326.
Liu, J. C., Wilson, A., Mickley, L. J., Dominici, F., Ebisu, K., Wang, Y., et al. (2017). Wildfire-specific Fine Particulate Matter and Risk of Hospital Admissions in Urban and Rural Counties. Epidemiology ,28 (1), 77–85. https://doi.org/10.1097/EDE.0000000000000556
Liu, XX, Zhang, Y, Huey, L. G., Yokelson, R. J., Wang, Y., Jimenez, J.L., et al. (2016). Agricultural fires in the southeastern US dur­ing SEAC4RS: Emissions of trace gases and particles and evolution of ozone, reactive nitrogen, and organic aerosol. J. Geophys. Res. Atmos. ,121 (12): 7383– 7414. DOI: https://doi.org/10.1002/2016jd025040
McCarty, J.L., Justice, C.O., & Korontzi, S. (2007). Agri­cultural burning in the Southeastern United States detected by MODIS.Remote Sens. Environ. , 108(2), 151– 162. DOI: https://doi.org/10.1016/j.rse.2006.03.020
McClure, C. D. & Jaffe, D. A. (2018). US particulate matter air quality improves except in wildfire-prone areas. Proceedings of the National Academy of Sciences , 115(31), 7901–7906. https://doi.org/10.1073/pnas.1804353115
Mesinger, F., DiMego, G., Kalnay, E., Mitchell, K., Shafran, P. C., Ebisuzaki, W., et al. (2006). North American Regional Reanalysis.Bull. Am. Meteorol. Soc. , 87(3), 343-360. doi: 10.1175/bams-87-3-343
Moeini, O., Tarasick, D. W., McElroy, C. T., Liu, J., Osman, M., Thompson, A. M., Parrington, M., Palmer, P. I., Johnson, B. J., Oltmans, S. J., Merrill, J. (2020). Estimating wildfire-generated ozone over North America using ozonesonde profiles and a differential back trajectory technique, Atmos. Environ.: X , 7, 100078, https://doi.org/10.1016/j.aeaoa.2020.100078.
Morris, G. A., Hersey, S., Thompson, A. M., Pawson, S., Nielsen, J. E., Colarco, P. R., et al. (2006). Alaskan and Canadian forest fires exacerbate ozone pollution over Houston, Texas, on 19 and 20 July 2004.J. Geophys. Res. , 111 (D24). doi: 10.1029/2006jd007090
Ott, L. E., Duncan, B. N., Thompson, A. M., Diskin, G., Fasnacht, Z., Langford, A. O., et al. (2016). Frequency and impact of summertime stratospheric intrusions over Maryland during DISCOVER-AQ (2011): New evi­dence from NASA’s GEOS-5 simulations. J. Geophys. Res. Atmos., 121 (7), 3687–3706. DOI: https://doi. org/10.1002/2015jd024052
Parrish, D. D., Aikin, K. C., Oltmans, S. J., Johnson, B. J., Ives, M., & Sweeny, C. (2010). Impact of transported background ozone inflow on summertime air qual­ity in a California ozone exceedance area.Atmos. Chem. Phys ., 10 (20), 10093–10109. DOI: https://doi. org/10.5194/acp-10-10093-2010
Parrish, D. D., Lamarque, J. F., Naik, V., Horowitz, L., Shindell, D. T., Staehelin, J., et al. (2014). Long-term changes in lower tropospheric baseline ozone concentrations: Comparing chem­istry-climate models and observations at northern midlatitudes. J. Geophys. Res. Atmos., 119 (9), 5719– 5736. DOI: https://doi.org/10.1002/2013jd021435
Parrish, D. D., Law, K. S., Staehelin, J., Derwent, R., Cooper, O. R., Tanimoto, et al. (2012). Long-term changes in lower tropospheric baseline ozone concentrations at northern mid-latitudes. Atmos. Chem. Phys., 12 , 11485–11504. DOI: https://doi.org/10.5194/acp-12-11485-2012
Paugam R., Wooster M., Freitas S., & Val Martin M. (2016) A review of approaches to estimate wildfire plume injection height within large-scale atmospheric chemical transport models. Atmos. Chem. Phys. , 16 , 907-925. doi: 10.5194/acp-16-907-2016
Peterson, D. A., Campbell, J. R., Hyer, E., Fromm, M., Kablick, G., Cossuth, J., & DeLand, M. (2018). Wildfire-driven thunderstorms cause a volcano-like stratospheric injection of smoke. NPJ Clim. Atmos. Sci. , 1 (30). doi:10.1038/s41612-018-0039-3
Peterson, D. A., Hyer, E. J., Campbell, J. R., Fromm, M. D., Hair, J. W., Butler, C. F., & Fenn, M. A. (2015). The 2013 Rim Fire: Implications for Predicting Extreme Fire Spread, Pyroconvection, and Smoke Emissions. Bull. Am. Meteorol. Soc. , 96, 229-247 . doi: 10.1175/bams-d-14-00060.1
Peterson, D. A., M. D. Fromm, J. E. Solbrig, E. J. Hyer, M. L. Surratt, & Campbell, J. R. (2017a). Detection and Inventory of Intense Pyroconvection in Western North America using GOES-15 Daytime Infrared Data. J. Appl. Meteorol. Climatol. , 56, 471-493.
Peterson, D. A., Hyer E. J., Campbell, J. R., Solbrig, J. E., & Fromm, M. D. (2017b) A conceptual model for development of intense pyrocumulonimbus in western north america.Mon. Weather Rev. , 145, 2235-2255. doi: 10.1175/mwr-d-16-0232.1
Peterson, D., Hyer, E., & Wang, J. (2014). Quantifying the potential for high-altitude smoke injection in the North American boreal forest using the standard MODIS fire products and subpixel-based methods.J. Geophys. Res.-Atmos , 119 , 2013JD021067.
Rappold, A. G., Reyes, J., Pouliot, G., Cascio, W. E., & Diaz-Sanchez, D. (2017) Community vulnerability to health impacts of wildland fire smoke exposure. Environ. Sci. Technol. , 51 , 6674-6682. doi: 10.1021/acs.est.6b06200
Reid, C. E., Brauer, M., Johnston, F. H., Jerrett, M., Balmes, J. R., & Elliott, C. T. (2016). Critical review of health impacts of wildfire smoke exposure. Environ. Health Perspect. , 124 , 1334.
Reid, J. S., Hyer, E., Prins, E. M., Westphal, D. L., Zhang, J., Wang, J., et al. (2009). Global Monitoring and Forecasting of Biomass-Burning Smoke: Description of and Lessons from the Fire Locating and Modeling of Burning Emissions (FLAMBE) Program. IEEE J. Sel. Top. Appl. ,2 (3), 144–162. Doi:10.1109/JSTARS.2009.2027443.
Rienecker, M. M., Suarez, M. J., Todling, R., Bacmeister, J., Takacs, L., Liu, H.-C., et al. (2008). The GEOS-5 Data Assimilation System—Documentation of Versions 5.0.1, 5.1.0, and 5.2.0. Technical Report Series on Global Modeling and Data Assimilation, 27.
Silva, R. A., West, J. J., Zhang, Y., Anenberg, S. C., Lamarque, J.-F., Shindell, D. T., et al. (2013). Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change. Environ. Res. Lett., 8 (3). DOI: https://doi. org/10.1088/1748-9326/8/3/034005
Simon, H., Reff, A., Wells, B., Xing, J., & Frank, N. (2015). Ozone trends across the United States over a period of decreasing NOx and VOC emissions. Envi­ron. Sci. Technol. , 49 (1), 186–195. DOI: https://doi. org/10.1021/es504514z
Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Duda, M. G., et al. (2008). A description of the Advanced Research WRF Version 3. Technical Note NCAR/TN-475+STR, National Center for Atmospheric Research, Boulder, Colorado, 113 pp.
Stajner, I., Wargan, K., Pawson, S., Hayashi, H., Chang, L.-P., Hudman, R. C., et al. (2008). Assimilated ozone from EOS-Aura: Evaluation of the tropopause region and tropospheric columns. J. Geophys. Res. ,113 (D16). doi: 10.1029/2007jd008863
Stauffer, R. M., Morris, G. A., Thompson, A. M., Joseph, E., Coetzee, G. J. R., & Nalli, N. R. (2014). Propagation of radiosonde pressure sensor errors to ozonesonde measurements. Atmos. Meas. Tech. , 7 , 65–79. doi:10.5194/amt-7-65-2014.
Stocks, B. J., Fosberg, M. A., Lynham, T. J., Mearns, L., Wotton, B. M., Yan, F., et al. (1998) Climate change and forest fire potential in russian and canadian boreal forest. Climate Change , 38 , 1-13.
Stohl, A. (2003). A backward modeling study of intercontinental pollution transport using aircraft measurements. J. Geophys. Res. , 108 (D12). doi: 10.1029/2002jd002862
Strode, S. A., Rodriguez, J. M., Logan, J. A., Cooper, O. R., Witte, J. C., Lamsal, L. N., et al. (2015). Trends and variability in surface ozone over the United States. J. Geophys. Res.-Atmos. ,120 (17), 9020–9042. DOI: https://doi.org/10.1002/2014JD022784
Sullivan, J. T., McGee, T. J., Thompson, A. M., Pierce, R. B., Sumnicht, G. K., Twigg, L., Eloranta, E., & Hoff, R. M. (2015). Characterizing the lifetime and occur­rence of stratospheric-tropospheric exchange events in the rocky mountain region using high-resolution ozone measurements. J. Geophys. Res.-Atmos., 120 (24), 12410–12424. DOI: https://doi. org/10.1002/2015jd023877
Thompson, A. M., Allen, A. L., Lee, S., Miller, S. K., & Witte, J. C. (2011a). Gravity and Rossby wave signatures in the tropical troposphere and lower stratosphere based on Southern Hemisphere Additional Ozonesondes (SHADOZ), 1998–2007. J. Geophys. Res. ,116 (D5). doi: 10.1029/2009jd013429
Thompson, A. M., Oltmans, S. J., Tarasick, D. W., von der Gathen, P., Smit, H. G. J., & Witte, J. C. (2011b). Strategic ozone sounding networks: Review of design and accomplishments. Atmos. Environ. ,45 (13), 2145-2163. doi: 10.1016/j.atmosenv.2010.05.002
Thompson, A. M., Smit, H. G., Witte, J. C., Stauffer, R. M., Johnson, B. J., Morris, G., et al. (2019). Ozonesonde Quality Assurance: The JOSIESHADOZ (2017) Experience. Bull. Amer. Meteor. Soc. ,100 , 155–171. https://doi.org/10.1175/BAMS-D-17-0311.1.
Thompson, A. M., Stone, J. B., Witte, J. C., Miller, S. K., Oltmans, S. J., Kucsera, T. L., et al. (2007). Intercontinental Chemical Transport Experiment Ozonesonde Network Study (IONS) 2004: 2. Tropospheric ozone budgets and variability over northeastern North America. Journal of Geophysical Research, 112(D12). doi: 10.1029/2006jd007670
Toon, O. B., Maring, H., Dibb, J., Ferrare, R., Jacob, D. J., Jensen, E. J., et al. (2016). Planning, implementation, and scientific goals of the studies of emissions and atmospheric composition, clouds and climate coupling by regional surveys (SEAC4RS) field mission. J. Geophys. Res.-Atmos. , 121 , 4967–5009.
Travis, K. R., Jacob, D. J., Fisher, J. A., Kim, P. S., Marais, E. A., Zhu, L., et al. (2016). Why do models overestimate surface ozone in the Southeast United States? Atmos. Chem. Phys. , 16 , 13561–13577, https://doi.org/10.5194/acp-16-13561-2016.
U.S. Environmental Protection Agency (US EPA). (2013). Integrated Science Assessment (ISA) of Ozone and Related Photochemical Oxidants (Final Report, Feb 2013). Washington, DC: U.S. Environmental Protection Agency. EPA/600/R-10/076F. Available at: https://cfpub.epa.gov/ncea/isa/recordisplay. cfm?deid=247492 Accessed October 27, 2019.
U.S. Environmental Protection Agency (US EPA). (2015). Implementation of the 2015 Primary Ozone NAAQS: Issues Associated with Background Ozone, White Paper for Discussion. Washington, DC: U.S. Environmental Protection Agency. Avail­able at: https://www.epa.gov/sites/production/ files/2016–03/documents/whitepaper-bgo3-final. pdf Accessed October 27, 2019.
Val Martin, M., Kahn, R. A., Logan, J. A., Paugam, R., Wooster, M., & Ichoku, C. (2012). Space-based observational constraints for 1-D fire smoke plume-rise models. J. Geophys. Res.-Atmos. ,117 (D22), n/a-n/a. doi: 10.1029/2012jd018370
Val Martin M., Kahn R. A., & Tosca M. G. (2018) A Global Analysis of Wildfire Smoke Injection Heights Derived from Space-Based Multi-Angle Imaging. Remote Sens. , 10 , 1609. doi:10.3390/rs10101609.
Wagner, N. L., Brock, C. A., Angevine, W. M., Beyersdorf, A., Campuzano-Jost, P., Day, D., et al. (2015). In situ vertical profiles of aerosol extinction, mass, and composition over the southeast United States during SENEX and SEAC4RS: observations of a modest aerosol enhancement aloft. Atmos. Chem. Phys. , 15 , 7085–7102. https://doi.org/10.5194/acp-15-7085-2015.
Wargan, K., Pawson, S., Olsen, M. A., Witte, J. C., Douglass, A. R., Ziemke, J. R., et al. (2015). The global structure of upper troposphere-lower stratosphere ozone in GEOS-5: A multiyear assimilation of EOS Aura data. J. Geophys. Res.-Atmos. , 120 , 2013-2036. doi: 10.1002/2014jd022493
Waugh, D. W., & Funatsu, B. M. (2003). Intrusions into the Tropical Upper Troposphere: Three-Dimensional Structure and Accompanying Ozone and OLR Distributions. J. Atmos. Sci. , 60, 637-653.
Westerling, A. L., Hidalgo, H. G., Cayan, D. R. & Swetnam, T. W. (2006). Warming and earlier spring increase western US forest wildfire activity. Science , 313 (5789), 940–943.
Westerling, A. L. (2016) Increasing western US forest wildfire activity: Sensitivity to changes in the timing of spring. Philos. Trans. R. Soc. B. Biol. Sci., 371 (1696):20150178.
Wilkins, J. L., Pouliot, G., Foley, K., Appel, W., & Pierce, T. (2018). The impact of US wildland fires on ozone and particulate matter: a comparison of measurements and CMAQ model predictions from 2008 to 2012.Int. J. Wildland Fire , 27 , 684–698. https://doi.org/10.1071/WF18053, 2018.
Zhu, L., Jacob, D. J., Kim, P. S., Fisher, J. A., Yu, K., Travis, K. R., et al. (2016) Observing atmospheric formaldehyde (HCHO) from space: validation and intercomparison of six retrievals from four satellites (OMI, GOME2A, GOME2B, OMPS) with SEAC4RS aircraft observations over the southeast US. Atmos. Chem. Phys. , 16 , 13477–13490. https://doi.org/10.5194/acp-16-13477-2016, 2016.