Abstract
Reducing surface ozone to meet the European Union’s target for human health has proven challenging despite stringent controls on ozone precursor emissions over recent decades. The most extreme ozone pollution episodes are linked to heatwaves and droughts, which are increasing in frequency and intensity over Europe, with severe impacts on natural and human systems. Here, we use observations and Earth system model simulations for the period 1960–2018 to show that ecosystem–atmosphere interactions, especially reduced ozone removal by water-stressed vegetation, exacerbate ozone air pollution over Europe. These vegetation feedbacks worsen peak ozone episodes during European mega-droughts, such as the 2003 event, offsetting much of the air quality improvements gained from regional emissions controls. As the frequency of hot and dry summers is expected to increase over the coming decades, this climate penalty could be severe and therefore needs to be considered when designing clean air policy in the European Union.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
Data availability
Ozone flux measurements, the ozone climate penalty factors derived from observations and model simulations generated in this study are archived at a public data repository at NOAA GFDL (ftp://data1.gfdl.noaa.gov/users/Meiyun.Lin/Nature2020/). Ozone deposition velocities from LM4.0 are archived at ftp://data1.gfdl.noaa.gov/users/Meiyun.Lin/GBC2019/GFDL‐LM4/. Source data for Figs. 1–6 and Extended Data Figs. 1–10 are provided with the paper.
Code availability
The computer code for the standard versions of GFDL’s atmospheric and land models is publicly available at https://www.gfdl.noaa.gov/atmospheric-model/. Other codes used in this study are available from the corresponding author upon reasonable request.
Change history
17 June 2020
A Correction to this paper has been published: https://doi.org/10.1038/s41558-020-0839-4
References
Vestreng, V. et al. Evolution of NOx emissions in Europe with focus on road transport control measures. Atmos. Chem. Phys. 9, 1503–1520 (2009).
Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on Ambient Air Quality and Cleaner air for Europe (European Union, 2008).
Communication from the Commission to the Council, the European Parliament, the European Economic and Social Committee and the Committee of the Regions—A Clean Air Programme for Europe (European Commission, 2013).
Directive 2016/2284/EC of the European Parliament and of the Council of 14 December 2016 on the Reduction of National Emissions of Certain Atmospheric Pollutants, Amending Directive 2003/35/EC and Repealing Directive 2001/81/EC (European Union, 2016).
Granier, C. et al. 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 (2011).
Monks, P. S. et al. Tropospheric ozone and its precursors from the urban to the global scale from air quality to short-lived climate forcer. Atmos. Chem. Phys. 15, 8889–8973 (2015).
Hoesly, R. M. et al. Historical (1750–2014) anthropogenic emissions of reactive gases and aerosols from the Community Emissions Data System (CEDS). Geosci. Model Dev. 11, 369–408 (2018).
Georgoulias, A. K., van der A., R. J., Stammes, P., Boersma, K. F. & Eskes, H. J. Trends and trend reversal detection in 2 decades of tropospheric NO2 satellite observations. Atmos. Chem. Phys. 19, 6269–6294 (2019).
Logan, J. A. et al. Changes in ozone over Europe: analysis of ozone measurements from sondes, regular aircraft (MOZAIC) and alpine surface sites. J. Geophys. Res. 117, D09301 (2012).
Parrish, D. D. et al. Long-term changes in lower tropospheric baseline ozone concentrations at northern mid-latitudes. Atmos. Chem. Phys. 12, 11485–11504 (2012).
Air Quality in Europe—2018 Report Report No. 12/2018 (European Environment Agency, 2018).
Exceedance of Air Quality Standards in Urban Areas (European Environment Agency, 2019).
Lelieveld, J. & Dentener, F. J. What controls tropospheric ozone? J. Geophys. Res. 105, 3531–3551 (2000).
Koumoutsaris, S. & Bey, I. Can a global model reproduce observed trends in summertime surface ozone levels? Atmos. Chem. Phys. 12, 6983–6998 (2012).
Colette, A. et al. Air quality trends in Europe over the past decade: a first multi-model assessment. Atmos. Chem. Phys. 11, 11657–11678 (2011).
Fusco, A. C. & Logan, J. A. Analysis of 1970–1995 trends in tropospheric ozone at Northern Hemisphere midlatitudes with the GEOS-CHEM model. J. Geophys. Res. 108, 4449 (2003).
Wild, O. et al. Modelling future changes in surface ozone: a parameterized approach. Atmos. Chem. Phys. 12, 2037–2054 (2012).
Lamarque, J. F. et al. Historical (1850–2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application. Atmos. Chem. Phys. 10, 7017–7039 (2010).
Parrish, D. D. et al. Long-term changes in lower tropospheric baseline ozone concentrations: comparing chemistry–climate models and observations at northern midlatitudes. J. Geophys. Res. 119, 5719–5736 (2014).
Lin, M. et al. Revisiting the evidence of increasing springtime ozone mixing ratios in the free troposphere over western North America. Geophys. Res. Lett. 42, 8719–8728 (2015).
Lin, M., Horowitz, L. W., Payton, R., Fiore, A. M. & Tonnesen, G. US surface ozone trends and extremes from 1980 to 2014: quantifying the roles of rising Asian emissions, domestic controls, wildfires, and climate. Atmos. Chem. Phys. 17, 2943–2970 (2017).
Fischer, E. M., Seneviratne, S. I., Luthi, D. & Schar, C. Contribution of land–atmosphere coupling to recent European summer heat waves. Geophys. Res. Lett. 34, L06707 (2007).
Seneviratne, S. I., Luthi, D., Litschi, M. & Schar, C. Land–atmosphere coupling and climate change in Europe. Nature 443, 205–209 (2006).
Hirschi, M. et al. Observational evidence for soil-moisture impact on hot extremes in southeastern Europe. Nat. Geosci. 4, 17–21 (2011).
Miralles, D. G., Teuling, A. J., van Heerwaarden, C. C. & de Arellano, J. V. G. Mega-heatwave temperatures due to combined soil desiccation and atmospheric heat accumulation. Nat. Geosci. 7, 345–349 (2014).
Rasmijn, L. M. et al. Future equivalent of 2010 Russian heatwave intensified by weakening soil moisture constraints. Nat. Clim. Change 8, 381–385 (2018).
Samaniego, L. et al. Anthropogenic warming exacerbates European soil moisture droughts. Nat. Clim. Change 8, 421–426 (2018).
Teuling, A. J. Climate hydrology: a hot future for European droughts. Nat. Clim. Change 8, 364–365 (2018).
Gerosa, G. et al. Comparison of seasonal variations of ozone exposure and fluxes in a Mediterranean holm oak forest between the exceptionally dry 2003 and the following year. Environ. Pollut. 157, 1737–1744 (2009).
Fowler, D. et al. Atmospheric composition change: ecosystems–atmosphere interactions. Atmos. Environ. 43, 5193–5267 (2009).
Rydsaa, J. H., Stordal, F., Gerosa, G., Finco, A. & Hodnebrog, O. Evaluating stomatal ozone fluxes in WRF-Chem: comparing ozone uptake in Mediterranean ecosystems. Atmos. Environ. 143, 237–248 (2016).
Hardacre, C., Wild, O. & Emberson, L. An evaluation of ozone dry deposition in global scale chemistry climate models. Atmos. Chem. Phys. 15, 6419–6436 (2015).
Silva, S. J. & Heald, C. L. Investigating dry deposition of ozone to vegetation. J. Geophys. Res. Atmos. 123, 559–573 (2018).
Morgenstern, O. et al. Review of the global models used within phase 1 of the Chemistry–Climate Model Initiative (CCMI). Geosci. Model Dev. 10, 639–671 (2017).
Wesely, M. L. Parameterization of surface resistances to gaseous dry deposition in regional-scale numerical models. Atmos. Environ. 23, 1293–1304 (1989).
Kavassalis, S. C. & Murphy, J. G. Understanding ozone–meteorology correlations: a role for dry deposition. Geophys. Res. Lett. 44, 2922–2931 (2017).
Andersson, C. & Engardt, M. European ozone in a future climate: importance of changes in dry deposition and isoprene emissions. J. Geophys. Res. Atmos. 115, D02303 (2010).
Emberson, L. D., Kitwiroon, N., Beevers, S., Buker, P. & Cinderby, S. Scorched Earth: how will changes in the strength of the vegetation sink to ozone deposition affect human health and ecosystems? Atmos. Chem. Phys. 13, 6741–6755 (2013).
Huang, L., McDonald-Buller, E. C., McGaughey, G., Kimura, Y. & Allen, D. T. The impact of drought on ozone dry deposition over eastern Texas. Atmos. Environ. 127, 176–186 (2016).
Lin, M. et al. Sensitivity of ozone dry deposition to ecosystem–atmosphere interactions: a critical appraisal of observations and simulations. Glob. Biogeochem. Cycles 33, 1264–1288 (2019).
Clifton, O. E., Fiore, A. M., Munger, J. W. & Wehr, R. Spatiotemporal controls on observed daytime ozone deposition velocity over northeastern U.S. forests during summer. J. Geophys. Res. Atmos. 124, 5612–5628 (2019).
Lombardozzi, D., Levis, S., Bonan, G., Hess, P. G. & Sparks, J. P. The influence of chronic ozone exposure on global carbon and water cycles. J. Clim. 28, 292–305 (2015).
Sadiq, M., Tai, A. P. K., Lombardozzi, D. & Martin, M. V. Effects of ozone–vegetation coupling on surface ozone air quality via biogeochemical and meteorological feedbacks. Atmos. Chem. Phys. 17, 3055–3066 (2017).
Bloomer, B. J., Stehr, J. W., Piety, C. A., Salawitch, R. J. & Dickerson, R. R. Observed relationships of ozone air pollution with temperature and emissions. Geophys. Res. Lett. 36, L09803 (2009).
Rasmussen, D. J. et al. Surface ozone–temperature relationships in the eastern US: a monthly climatology for evaluating chemistry–climate models. Atmos. Environ. 47, 142–153 (2012).
Paulot, F. et al. Representing sub-grid scale variations in nitrogen deposition associated with land use in a global Earth system model: implications for present and future nitrogen deposition fluxes over North America. Atmos. Chem. Phys. 18, 17963–17978 (2018).
Lin, M., Horowitz, L. W., Oltmans, S. J., Fiore, A. M. & Fan, S. Tropospheric ozone trends at Mauna Loa Observatory tied to decadal climate variability. Nat. Geosci. 7, 136–143 (2014).
Jarvis, P. G. Interpretation of variations in leaf water potential and stomatal conductance found in canopies in field. Phil. Trans. R. Soc. Lond. B 273, 593–610 (1976).
von Schneidemesser, E., Monks, P. S. & Plass-Duelmer, C. Global comparison of VOC and CO observations in urban areas. Atmos. Environ. 44, 5053–5064 (2010).
Barriopedro, D., Fischer, E. M., Luterbacher, J., Trigo, R. & Garcia-Herrera, R. The hot summer of 2010: redrawing the temperature record map of Europe. Science 332, 220–224 (2011).
Russo, S., Sillmann, J. & Fischer, E. M. Top ten European heatwaves since 1950 and their occurrence in the coming decades. Environ. Res. Lett. 10, 124003 (2015).
Fischer, E. M., Seneviratne, S. I., Vidale, P. L., Luthi, D. & Schar, C. Soil moisture–atmosphere interactions during the 2003 European summer heat wave. J. Clim. 20, 5081–5099 (2007).
Sheffield, J. & Wood, E. F. Drought: Past Problems and Future Scenarios (Earthscan, 2011).
Mora, C. et al. Global risk of deadly heat. Nat. Clim. Change 7, 501–506 (2017).
Robine, J. M. et al. Death toll exceeded 70,000 in Europe during the summer of 2003. C. R. Biol. 331, 171–178 (2008).
Dear, K., Ranmuthugala, G., Kjellstrom, T., Skinner, C. & Hanigan, I. Effects of temperature and ozone on daily mortality during the August 2003 heat wave in France. Arch. Environ. Occup. Health 60, 205–212 (2005).
Christidis, N., Jones, G. S. & Stott, P. A. Dramatically increasing chance of extremely hot summers since the 2003 European heatwave. Nat. Clim. Change 5, 46–50 (2015).
Horton, D. E. et al. Contribution of changes in atmospheric circulation patterns to extreme temperature trends. Nature 522, 465–469 (2015).
Jacob, D. J. & Winner, D. A. Effect of climate change on air quality. Atmos. Environ. 43, 51–63 (2009).
Fiore, A. M., Naik, V. & Leibensperger, E. M. Air quality and climate connections. J. Air Waste Manage. Assoc. 65, 645–685 (2015).
Sillman, S. & Samson, F. J. Impact of temperature on oxidant photochemistry in urban, polluted rural and remote environments. J. Geophys. Res. Atmos. 100, 11497–11508 (1995).
Pusede, S. E., Steiner, A. L. & Cohen, R. C. Temperature and recent trends in the chemistry of continental surface ozone. Chem. Rev. 115, 3898–3918 (2015).
Guenther, A. B. et al. The Model of Emissions of Gases and Aerosols from Nature version 2.1 (MEGAN2.1): an extended and updated framework for modeling biogenic emissions. Geosci. Model Dev. 5, 1471–1492 (2012).
Yienger, J. J. & Levy, H. Empirical-model of global soil-biogenic NOx emissions. J. Geophys. Res. Atmos. 100, 11447–11464 (1995).
Hudman, R. C., Russell, A. R., Valin, L. C. & Cohen, R. C. Interannual variability in soil nitric oxide emissions over the United States as viewed from space. Atmos. Chem. Phys. 10, 9943–9952 (2010).
Oikawa, P. Y. et al. Unusually high soil nitrogen oxide emissions influence air quality in a high-temperature agricultural region. Nat. Commun. 6, 8753 (2015).
Jaffe, D. & Wigder, N. L. Ozone production from wildfires: a critical review. Atmos. Environ. 51, 1–10 (2012).
Demetillo, M. A. G. et al. Observing severe drought influences on ozone air pollution in California. Environ. Sci. Technol. 53, 4695–4706 (2019).
Begueria, S., Vicente-Serrano, S. M., Reig, F. & Latorre, B. Standardized Precipitation Evapotranspiration Index (SPEI) revisited: parameter fitting, evapotranspiration models, tools, datasets and drought monitoring. Int. J. Clim. 34, 3001–3023 (2014).
Sheffield, J., Goteti, G. & Wood, E. F. Development of a 50-year high-resolution global dataset of meteorological forcings for land surface modeling. J. Clim. 19, 3088–3111 (2006).
Hoerling, M. et al. On the increased frequency of Mediterranean drought. J. Clim. 25, 2146–2161 (2012).
Seager, R. et al. Climate variability and change of Mediterranean-type climates. J. Clim. 32, 2887–2915 (2019).
Dai, A. G. Increasing drought under global warming in observations and models. Nat. Clim. Change 3, 52–58 (2013).
Sheffield, J., Wood, E. F. & Roderick, M. L. Little change in global drought over the past 60 years. Nature 491, 435–438 (2012).
Milly, P. C. D. & Dunne, K. A. Potential evapotranspiration and continental drying. Nat. Clim. Change 6, 946–949 (2016).
Derwent, R. G., Simmonds, P. G., Manning, A. J. & Spain, T. G. Trends over a 20-year period from 1987 to 2007 in surface ozone at the atmospheric research station, Mace Head, Ireland. Atmos. Environ. 41, 9091–9098 (2007).
Zhang, Y. H., Seidel, D. J. & Zhang, S. D. Trends in planetary boundary layer height over Europe. J. Clim. 26, 10071–10076 (2013).
Konovalov, I. B., Beekmann, M., Kuznetsova, I. N., Yurova, A. & Zvyagintsev, A. M. Atmospheric impacts of the 2010 Russian wildfires: integrating modelling and measurements of an extreme air pollution episode in the Moscow region. Atmos. Chem. Phys. 11, 10031–10056 (2011).
Porter, W. C., Heald, C. L., Cooley, D. & Russell, B. Investigating the observed sensitivities of air-quality extremes to meteorological drivers via quantile regression. Atmos. Chem. Phys. 15, 10349–10366 (2015).
Climate Change and the US Energy Sector: Regional Vulnerabilities and Resilience Solutions (DOE, 2015).
Report from the Commission to the European Parliament, the European Economic and Social Committee and the Committee of the Regions—“The First Clean Air Outlook” (European Commission, 2018).
European Monitoring and Evaluation Program (EMEP) Measurement Data (EMEP, 2019); https://projects.nilu.no/CCC/emepdata.html
European Air Quality Portal (European Environment Agency, 2020); http://discomap.eea.europa.eu/map/fme/AirQualityExport.htm
Schultz, M. G. et al. Tropospheric ozone assessment report: database and metrics data of global surface ozone observations. Elementa 5, 58 (2017).
Harris, I., Jones, P. D., Osborn, T. J. & Lister, D. H. Updated high-resolution grids of monthly climatic observations—the CRU TS3.10 Dataset. Int. J. Clim. 34, 623–642 (2014).
Donat, M. et al. Global land-based datasets for monitoring climatic extremes. Bull. Amer. Meteor. Soc. 94, 997–1006 (2013).
Pilegaard, K., Jensen, N. O. & Hummelshoj, P. Seasonal and diurnal variation in the deposition velocity of ozone over a spruce forest in Denmark. Water Air Soil Pollut. 85, 2223–2228 (1995).
Webb, E. K., Pearman, G. I. & Leuning, R. Correction of flux measurements for density effects due to heat and water vapour transfer. Q. J. R. Meteorol. Soc. 106, 85–100 (1980).
Vickers, D. & Mahrt, L. Quality control and flux sampling problems for tower and aircraft data. J. Atmos. Ocean Technol. 14, 512–526 (1997).
Shevliakova, E. et al. Carbon cycling under 300 years of land use change: importance of the secondary vegetation sink. Global Biogeochem. Cycles 23, Gb2022 (2009).
Malyshev, S., Shevliakova, E., Stouffer, R. J. & Pacala, S. W. Contrasting local versus regional effects of land-use-change-induced heterogeneity on historical climate: analysis with the GFDL Earth system model. J. Clim. 28, 5448–5469 (2015).
Zhao, M. et al. The GFDL global atmosphere and land model AM4.0/LM4.0:2. Model description, sensitivity studies, and tuning strategies. J. Adv. Model. Earth Syst. 10, 735–769 (2018).
Zhao, M. et al. The GFDL global atmosphere and land model AM4.0/LM4.0:1. Simulation characteristics with prescribed SSTs. J. Adv. Model. Earth Syst. 10, 691–734 (2018).
Hurtt, G. C. et al. Harmonization of land-use scenarios for the period 1500–2100: 600 years of global gridded annual land-use transitions, wood harvest, and resulting secondary lands. Climatic Change 109, 117–161 (2011).
Zhang, L. M., Brook, J. R. & Vet, R. A revised parameterization for gaseous dry deposition in air-quality models. Atmos. Chem. Phys. 3, 2067–2082 (2003).
Massman, W. J. Toward an ozone standard to protect vegetation based on effective dose: a review of deposition resistances and a possible metric. Atmos. Environ. 38, 2323–2337 (2004).
Weng, E. S. et al. Scaling from individual trees to forests in an Earth system modeling framework using a mathematically tractable model of height-structured competition. Biogeosciences 12, 2655–2694 (2015).
Milly, P. C. D. et al. An enhanced model of land water and energy for global hydrologic and Earth-system studies. J. Hydrometeorol. 15, 1739–1761 (2014).
Lammertsma, E. I. et al. Global CO2 rise leads to reduced maximum stomatal conductance in Florida vegetation. Proc. Natl Acad. Sci. USA 108, 4035–4040 (2011).
Lin, M. et al. Transport of Asian ozone pollution into surface air over the western United States in spring. J. Geophys. Res. 117, D00V07 (2012).
Lin, M. et al. Climate variability modulates western US ozone air quality in spring via deep stratospheric intrusions. Nat. Commun. 6, 7105 (2015).
van der Werf, G. R. et al. Global fire emissions estimates during 1997–2016. Earth Syst. Sci. Data 9, 697–720 (2017).
Horowitz, L. W. Past, present, and future concentrations of tropospheric ozone and aerosols: methodology, ozone evaluation, and sensitivity to aerosol wet removal. J. Geophys. Res. 111, D22211 (2006).
Hassler, B. et al. Analysis of long-term observations of NOx and CO in megacities and application to constraining emissions inventories. Geophys. Res. Lett. 43, 9920–9930 (2016).
Duncan, B. N. et al. A space-based, high-resolution view of notable changes in urban NOx pollution around the world (2005–2014). J. Geophys. Res. 121, 976–996 (2016).
Acknowledgements
This report was prepared by M. Lin under awards NA14OAR4320106 and NA18OAR4320123 from the National Oceanic and Atmospheric Administration (NOAA), US Department of Commerce. The statements, findings, conclusions and recommendations are those of the authors and do not necessarily reflect the views of NOAA. We thank GFDL internal reviewers, K. Dixon and J. Krasting, for constructive comments, which have helped to strengthen the article.
Author information
Authors and Affiliations
Contributions
M.L. conceived this study, performed the model experiments and analysis, and wrote the article. M.L., L.W.H. and E.S. designed the model experiments. Y.X. performed the ozone–temperature regression analysis under the supervision of M.L. F.P., M.L., S.M. and E.S. developed the dry deposition scheme. A.F., G.G. and K.P. provided ozone flux measurements. D.K. provided surface ozone measurements at Hohenpeissenberg. All authors contributed to discussions and edited the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Peer review information Nature Climate Change thanks Elena McDonald-Buller and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Extended data
Extended Data Fig. 1 Ozone-temperature relationships.
Scatter plots of observed June-August mean MDA8 ozone anomalies (relative to 1980–2000) at Hohenpeissenberg and Zugspitze and observed June-August mean Tmax anomalies averaged over 42°–53°N and 0°–15°E, with linear regression fits using the Ordinary Least Squares (OLS, blue) and Reduced Major Axis (RMA, red) methods, respectively. The OLS regression slopes are reported in Fig. 1 in the main article.
Extended Data Fig. 2 Trends in ozone precursor emissions.
a, b, Trends in anthropogenic emissions of carbon monoxide and non-methane volatile organic compounds (NMVOCs) in Europe (40–60N; 10W–25E) from the CMIP6 historical dataset used by the model. c, Observed trends in global average methane mixing ratios used by the model. d, Model estimated trends in biogenic isoprene emissions over Europe (40°–60°N;10°W–25°E).
Extended Data Fig. 3 Surface ozone trends.
Maps of the 1990–2015 trends in daily MDA8 ozone for the 95th and 50th percentiles in July and August from observations (top) and IAVDEPV simulations (bottom). Results are shown for EMEP sites with at least 20 years of data, with larger circles indicating sites with significant ozone trends (p < 0.05). The percentage of sites with significant trends are reported at the top-left corner of each graph.
Extended Data Fig. 4 Ozone pollution during the 2015 and 2018 heatwaves.
(Top) Maps of observed daily maximum temperature anomalies in June-August of 2015 and 2018 relative to the base period 1961–1990, with dots indicating area in drought (SPEI06 <−1). (Middle) The annual 4th highest MDA8 ozone concentrations from all available observations gridded at 0.5° resolution, with values above 70 ppb implying an exceedance of the health limit set by the U.S. Environmental Protection Agency. (Bottom) The annual 26th highest MDA8 ozone concentrations, with values above 60 ppb implying an exceedance of the health limit set by the European Union.
Extended Data Fig. 5 Evolution of drought events.
The Standardized Precipitation-Evapotranspiration Index (SPEI) integrated over the preceding 6 months, 2 months, and 1 month for August 2003, July 1994 and July 2006.
Extended Data Fig. 6 Land use.
a, Fraction of the four land use categories in each grid cell averaged over 2000–2015: Natural forests (lands undisturbed by human activities), secondary vegetation (lands harvested at least once, including managed forests and abandoned cropland and pasture), croplands, and pastures. b, Changes in 2000–2015 relative to the 1960s. The box denotes the area used for averaging in Extended Data Fig. 7.
Extended Data Fig. 7 Declining ozone removal by vegetation due to stomatal closure under soil drying as opposed to land use changes.
a, b, Evolution of land use over western Europe (5°W–25°E and 40°–55°N): total land areas and area-weighted leaf area indices for natural forests (dark green), secondary vegetation (green), croplands (orange), and pastures (blue). c, Evolution of June-August mean daytime ozone deposition velocities for the four land use types (area-weighted). d, Total (solid green lines) and stomatal (dashed green lines) ozone deposition velocities averaged over natural and secondary vegetation land areas. The vertical bars show the percentage of land areas in drought (SPEI06<−1; right axis).
Extended Data Fig. 8 Climate-driven trends in surface ozone over Europe.
Maps of the 1979–2014 and 1990–2014 trends in the 95th and 50th percentile MDA8 ozone concentrations for July (a) and August (b), simulated by the IAVDEPV_FIXEM experiment with anthropogenic emissions held constant at 1980 levels. Stippling denotes areas where the change is statistically significant at the 95% confidence level (p < 0.05).
Extended Data Fig. 9 Observed trends in hot extremes over Europe.
Maps of the 1979–2019 trends in the frequency of warm days (that is, those above the 90th percentile for the base period 1961–1990) in July (a) and August (b), respectively, obtained from the Global Land-Based Datasets for Monitoring Climate Extremes (Methods). Stippling denotes areas where the change is statistically significant (p < 0.05).
Extended Data Fig. 10 Drivers of decadal mean ozone trends in Europe.
Changes in decadal mean ozone levels during spring (March-May) and summer (June-August) from 1979–1989 to 2001–2010 as inferred from surface observations at Hohenpeissenberg (985 m altitude, MDA8 values), from alpine observations at Zugspitze (2962 m altitude, 24-hour mean), and from 1990–2000 to 2001–2010 at 52 EMEP sites over 40°N–55°N with continuous observations (MDA8 values). For observations, both changes in decadal mean (grey bars) and median (circles) values are shown, with the error bars indicating the range of the mean change at the 95% confidence level. Model results are shown for the BASE (total; red bars) and IAVDEPV_FIXEM (climate-driven trends; green bars) experiments and the contributions from changes in Asian anthropogenic emissions (purple bars), global methane concentrations (cyan bars), and wildfire emissions (yellow bars). For comparisons with free tropospheric observations at the Zugspitze, model results are sampled at 700 hPa.
Source data
Source Data Fig. 1
Statistical source data.
Source Data Fig. 2
Statistical source data.
Source Data Fig. 3
Statistical source data.
Source Data Fig. 4
Statistical source data.
Source Data Fig. 5
Statistical source data.
Source Data Extended Data Fig. 1
Statistical source data.
Source Data Extended Data Fig. 2
Statistical source data.
Source Data Extended Data Fig. 3
Statistical source data.
Source Data Extended Data Fig. 7
Statistical source data.
Source Data Extended Data Fig. 10
Statistical source data.
Rights and permissions
About this article
Cite this article
Lin, M., Horowitz, L.W., Xie, Y. et al. Vegetation feedbacks during drought exacerbate ozone air pollution extremes in Europe. Nat. Clim. Chang. 10, 444–451 (2020). https://doi.org/10.1038/s41558-020-0743-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s41558-020-0743-y
This article is cited by
-
Air quality improvements can strengthen China’s food security
Nature Food (2024)
-
Recent PM2.5 air quality improvements in India benefited from meteorological variation
Nature Sustainability (2024)
-
A novel semi data dimension reduction type weighting scheme of the multi-model ensemble for accurate assessment of twenty-first century drought
Stochastic Environmental Research and Risk Assessment (2024)
-
Air Pollution Interactions with Weather and Climate Extremes: Current Knowledge, Gaps, and Future Directions
Current Pollution Reports (2024)
-
A cautious note advocating the use of ensembles of models and driving data in modeling of regional ozone burdens
Air Quality, Atmosphere & Health (2024)