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The severity and extent of the Australia 2019–20 Eucalyptus forest fires are not the legacy of forest management

Matters Arising to this article was published on 14 April 2022


The 2019–20 wildfires in eastern Australia presented a globally important opportunity to evaluate the respective roles of climatic drivers and natural and anthropogenic disturbances in causing high-severity fires. Here, we show the overwhelming dominance of fire weather in causing complete scorch or consumption of forest canopies in natural and plantation forests in three regions across the geographic range of these fires. Sampling 32% (2.35 Mha) of the area burnt we found that >44% of the native forests suffered severe canopy damage. Past logging and wildfire disturbance in natural forests had a very low effect on severe canopy damage, reflecting the limited extent logged in the last 25 years (4.5% in eastern Victoria, 5.3% in southern New South Wales (NSW) and 7.8% in northern NSW). The most important variables determining severe canopy damage were broad spatial factors (mostly topographic) followed by fire weather. Timber plantations affected by fire were concentrated in NSW and 26% were burnt by the fires and >70% of the NSW plantations suffered severe canopy damage showing that this intensive means of wood production is extremely vulnerable to wildfire. The massive geographic scale and severity of these Australian fires is best explained by extrinsic factors: an historically anomalous drought coupled with strong, hot dry westerly winds that caused uninterrupted, and often dangerous, fire weather over the entire fire season.

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Fig. 1: Geographic extent of the 2019–20 east coast Australian fires that burnt in the temperate Eucalyptus forest domain.
Fig. 2: Relative importance of variable in driving fire severity.
Fig. 3: Marginal effects of forest history on fire severity.
Fig. 4: Map of plantations and 2019/20 fire boundaries, with relative proportion of canopy impact classes.
Fig. 5: Daily McArthur Forest Fire Danger Index (FFDI) for the three case-study fire areas.

Data availability

Satellite-based fire severity mapping based on Sentinel-2 satellite imagery38 was obtained for the Victorian fires from the Victorian Department of Environment, Land, Water and Planning and is available on the Victoria government spatial data portal ( Severity classes were calculated for the NSW fires using the fire extent and severity algorithm (FESM) developed by Gibson et al.39 and are available on the NSW SEED data portal ( Forest harvest date for Victoria was obtained from the Victorian Department of Environment, Land, Water and Planning and is available on the Victoria government spatial data portal ( Forest harvest date for NSW was obtained from NSW Forestry Corp on request, with data for older age classes within NSW supplemented with statewide land cover and trees study (SLATS) data provided by NSW Department of Planning, Industry and Environment. The 2017 NSW Landuse mapping was obtained from the NSW seed data portal ( Fire history and fire progression isochrons were obtained from the Victorian Department of Environment, Land, Water and Planning ( and were provided by the NSW Rural Fire Service for NSW. Gridded FFDI data are available from the Bureau of Meteorology60. TPI was calculated from the NASA Shuttle Radar Topography Mission 90-m digital elevation model with a window of 250 m (ref. 62). Vegetation type was derived from the National Vegetation Inventory System 4.1 ( for Victoria and from the state vegetation formation dataset for NSW (

Code availability

Code for the analyses is available on FigShare at the following URL:


  1. Bowman, D. M. J. S. et al. Fire in the Earth system. Science 324, 481–484 (2009).

    CAS  PubMed  Google Scholar 

  2. Davis, K. T. et al. Wildfires and climate change push low-elevation forests across a critical climate threshold for tree regeneration. Proc. Natl Acad. Sci. USA 116, 6193–6198 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  3. Enright, N. J., Fontaine, J. B., Bowman, D. M. J. S., Bradstock, R. A. & Williams, R. J. Interval squeeze: altered fire regimes and demographic responses interact to threaten woody species persistence as climate changes. Front. Ecol. Environ. 13, 265–272 (2015).

    Google Scholar 

  4. Abatzoglou, J. T. & Williams, A. P. Impact of anthropogenic climate change on wildfire across western US forests. Proc. Natl Acad. Sci. USA 113, 11770–11775 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  5. Bowman, D. M. J. S. et al. Vegetation fires in the Anthropocene. Nat. Rev. Earth Environ. 1, 500–515 (2020).

    Google Scholar 

  6. Keeley, J. E., van Mantgem, P. & Falk, D. A. Fire, climate and changing forests. Nat. Plants 5, 774–775 (2019).

    PubMed  Google Scholar 

  7. Lindenmayer, D. B., Kooyman, R. M., Taylor, C., Ward, M. & Watson, J. E. Recent Australian wildfires made worse by logging and associated forest management. Nat. Ecol. Evol. 4, 898–900 (2020).

    PubMed  Google Scholar 

  8. Murphy, B. P. et al. Fire regimes of Australia: a pyrogeographic model system. J. Biogeogr. 40, 1048–1058 (2013).

    Google Scholar 

  9. Poulos, H. M., Barton, A. M., Slingsby, J. A. & Bowman, D. M. J. S. Do mixed fire regimes shape plant flammability and post-fire recovery strategies? Fire 1, 39 (2018).

    Article  Google Scholar 

  10. Cawson, J. G. et al. Exploring the key drivers of forest flammability in wet eucalypt forests using expert-derived conceptual models. Landsc. Ecol. 35, 1775–1798 (2020).

    Google Scholar 

  11. Thomas, P. B., Watson, P. J., Bradstock, R. A., Penman, T. D. & Price, O. Modelling surface fine fuel dynamics across climate gradients in eucalypt forests of south‐eastern Australia. Ecography 37, 827–837 (2014).

    Google Scholar 

  12. Bennett, L. T. et al. Mortality and recruitment of fire-tolerant eucalypts as influenced by wildfire severity and recent prescribed fire. For. Ecol. Manag. 380, 107–117 (2016).

    Google Scholar 

  13. Fairman, T. A., Bennett, L. T., Tupper, S. & Nitschke, C. R. Frequent wildfires erode tree persistence and alter stand structure and initial composition of a fire‐tolerant sub‐alpine forest. J. Veg. Sci. 28, 1151–1165 (2017).

    Google Scholar 

  14. Prior, L. D., Williamson, G. J. & Bowman, D. M. J. S. Impact of high-severity fire in a Tasmanian dry eucalypt forest. Aust. J. Bot. 64, 193–205 (2016).

    Google Scholar 

  15. Bassett, O. D., Prior, L. D., Slijkerman, C. M., Jamieson, D. & Bowman, D. M. J. S. Aerial sowing stopped the loss of alpine ash (Eucalyptus delegatensis) forests burnt by three short-interval fires in the Alpine National Park, Victoria, Australia. For. Ecol. Manag. 342, 39–48 (2015).

    Google Scholar 

  16. Bowman, D. et al. Wildfires: Australia needs national monitoring agency. Nature 584, 188–191 (2020).

    CAS  PubMed  Google Scholar 

  17. King, A. D., Pitman, A. J., Henley, B. J., Ukkola, A. M. & Brown, J. R. The role of climate variability in Australian drought. Nat. Clim. Change 10, 177–179 (2020).

    Google Scholar 

  18. Sharples, J. J. et al. Natural hazards in Australia: extreme bushfire. Clim. Change 139, 85–99 (2016).

    Google Scholar 

  19. Bowman, D. M. J. S., Williamson, G. J., Price, O. F., Ndalila, M. N. & Bradstock, R. A. Australian forests, megafires and the risk of dwindling carbon stocks. Plant, Cell Environ. 44, 347–355 (2020).

  20. Khaykin, S. et al. The 2019/20 Australian wildfires generated a persistent smoke-charged vortex rising up to 35 km altitude. Commun. Earth Environ. 1, 22 (2020).

    Google Scholar 

  21. Borchers Arriagada, N. et al. Unprecedented smoke-related health burden associated with the 2019–20 bushfires in eastern Australia. Med. J. Aust. 213, 282–283 (2020).

  22. Johnston, F. H. et al. Unprecedented health costs of smoke-related PM2.5 from the 2019–20 Australian megafires. Nat. Sustain. 4, 42–47 (2021).

    Google Scholar 

  23. Ward, M. et al. Impact of 2019–2020 mega-fires on Australian fauna habitat. Nat. Ecol. Evol. 4, 1321–1326 (2020).

    PubMed  Google Scholar 

  24. Bowman, D. M. J. S., Williamson, G. J., Prior, L. D. & Murphy, B. P. The relative importance of intrinsic and extrinsic factors in the decline of obligate seeder forests. Glob. Ecol. Biogeogr. 25, 1166–1172 (2016).

    Google Scholar 

  25. Povak, N. A., Kane, V. R., Collins, B. M., Lydersen, J. M. & Kane, J. T. Multi-scaled drivers of severity patterns vary across land ownerships for the 2013 Rim Fire, California. Landsc. Ecol. 35, 293–318 (2020).

    Google Scholar 

  26. Parks, S. A. et al. High-severity fire: evaluating its key drivers and mapping its probability across western US forests. Environ. Res. Lett. 13, 044037 (2018).

    Google Scholar 

  27. Fang, L., Yang, J., Zu, J., Li, G. & Zhang, J. Quantifying influences and relative importance of fire weather, topography, and vegetation on fire size and fire severity in a Chinese boreal forest landscape. For. Ecol. Manag. 356, 2–12 (2015).

    Google Scholar 

  28. Thompson, J. R. & Spies, T. A. Vegetation and weather explain variation in crown damage within a large mixed-severity wildfire. For. Ecol. Manag. 258, 1684–1694 (2009).

    Google Scholar 

  29. Stephens, S. L. et al. Fire and climate change: conserving seasonally dry forests is still possible. Front. Ecol. Environ. 18, 354–360 (2020).

    Google Scholar 

  30. Dieleman, C. M. et al. Wildfire combustion and carbon stocks in the southern Canadian boreal forest: implications for a warming world. Glob. Change Biol. 26, 6062–6079 (2020).

    Google Scholar 

  31. Nolan, R. H. et al. Causes and consequences of eastern Australia’s 2019–20 season of mega‐fires. Glob. Change Biol. 26, 1039–1041 (2020).

  32. Boer, M. M., Resco de Dios, V. & Bradstock, R. A. Unprecedented burn area of Australian mega forest fires. Nat. Clim. Change 10, 171–172 (2020).

    Google Scholar 

  33. van Oldenborgh, G. J. et al. Attribution of the Australian bushfire risk to anthropogenic climate change. Nat. Hazards Earth Syst. Sci. 21, 941–960 (2021).

    Google Scholar 

  34. Adams, M. A., Shadmanroodposhti, M. & Neumann, M. Letter to the Editor. Causes and consequences of Eastern Australia’s 2019‐20 season of mega‐fires: a broader perspective. Glob. Change Biol. 26, 3756–3758 (2020).

  35. Lindenmayer, D. B. & Taylor, C. New spatial analyses of Australian wildfires highlight the need for new fire, resource, and conservation policies. Proc. Natl Acad. Sci. USA 117, 12481–12485 (2020).

    CAS  PubMed  PubMed Central  Google Scholar 

  36. Lindenmayer, D. B., Hobbs, R. J., Likens, G. E., Krebs, C. J. & Banks, S. C. Newly discovered landscape traps produce regime shifts in wet forests. Proc. Natl Acad. Sci. USA 108, 15887–15891 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  37. Taylor, C., McCarthy, M. A. & Lindenmayer, D. B. Nonlinear effects of stand age on fire severity. Conserv. Lett. 7, 355–370 (2014).

    Google Scholar 

  38. Collins, L., Griffioen, P., Newell, G. & Mellor, A. The utility of Random Forests for wildfire severity mapping. Remote Sens. Environ. 216, 374–384 (2018).

    Google Scholar 

  39. Gibson, R., Danaher, T., Hehir, W. & Collins, L. A remote sensing approach to mapping fire severity in south-eastern Australia using sentinel 2 and random forest. Remote Sens. Environ. 240, 111702 (2020).

    Google Scholar 

  40. Collins, L., Bradstock, R. & Penman, T. Can precipitation influence landscape controls on wildfire severity? A case study within temperate eucalypt forests of south-eastern Australia. Int. J. Wildland Fire 23, 9–20 (2014).

    Google Scholar 

  41. Price, O. F. & Bradstock, R. A. The efficacy of fuel treatment in mitigating property loss during wildfires: insights from analysis of the severity of the catastrophic fires in 2009 in Victoria, Australia. J. Environ. Manag. 113, 146–157 (2012).

    Google Scholar 

  42. Storey, M., Price, O. & Tasker, E. The role of weather, past fire and topography in crown fire occurrence in eastern Australia. Int. J. Wildland Fire 25, 1048–1060 (2016).

    Google Scholar 

  43. Bradstock, R. A., Hammill, K. A., Collins, L. & Price, O. Effects of weather, fuel and terrain on fire severity in topographically diverse landscapes of south-eastern Australia. Landsc. Ecol. 25, 607–619 (2010).

    Google Scholar 

  44. Taylor, C., Blanchard, W. & Lindenmayer, D. B. Does forest thinning reduce fire severity in Australian eucalypt forests? Conserv. Lett. (2020).

  45. Lydersen, J. M. et al. Evidence of fuels management and fire weather influencing fire severity in an extreme fire event. Ecol. Appl. 27, 2013–2030 (2017).

    PubMed  Google Scholar 

  46. Gómez-González, S., Ojeda, F. & Fernandes, P. M. Portugal and Chile: longing for sustainable forestry while rising from the ashes. Environ. Sci. Policy 81, 104–107 (2018).

    Google Scholar 

  47. Bowman, D. M. J. S. et al. Human–environmental drivers and impacts of the globally extreme 2017 Chilean fires. Ambio 48, 350–362 (2019).

    PubMed  Google Scholar 

  48. Jackson, W. Fire, air, water and earth–an elemental ecology of Tasmania. Proc. Ecol. Soc. Aust. 3, 9–16 (1968).

    Google Scholar 

  49. Tolhurst, K. G. & McCarthy, G. Effect of prescribed burning on wildfire severity: a landscape-scale case study from the 2003 fires in Victoria. Aust. For. 79, 1–14 (2016).

    Google Scholar 

  50. Gammage, B. The Biggest Estate on Earth: How Aborigines Made Australia (Allen & Unwin, 2011).

  51. Dargavel, J. Views and perspectives: why does Australia have ‘forest wars’? Int. Rev. Environ. Hist. 4, 33–51 (2018).

    Google Scholar 

  52. Kanowski, P. J. Australia’s forests: contested past, tenure-driven present, uncertain future. For. Policy Econ. 77, 56–68 (2017).

    Google Scholar 

  53. Australian Forest and Wood Products Statistics Mar-Jun 2019 (Australian Bureau of Agricultural and Resource Economics and Sciences, 2019).

  54. Ferguson, I. Australian plantations: mixed signals ahead. Int. For. Rev. 16, 160–171 (2014).

    Google Scholar 

  55. Raison, R. & Squire, R. Forest Management in Australia: Implications for Carbon Budgets Technical Report 32 (Australian Greenhouse Office, 2008).

  56. Proctor, E. & McCarthy, G. Changes in fuel hazard following thinning operations in mixed-species forests in East Gippsland, Victoria. Aust. For. 78, 195–206 (2015).

    Google Scholar 

  57. NSW Regional Forest Agreements Assessment of Matters Pertaining to Renewal of Regional Forest Agreements (NSW Department of Primary Industries, 2018).

  58. Evans, J. spatialEco_. R package version 1.3-1 (2020).

  59. Farr, T. G. et al. The shuttle radar topography mission. Rev. Geophys. (2007).

  60. Dowdy, A. J. Climatological variability of fire weather in Australia. J. Appl. Meteorol. Climatol. 57, 221–234 (2018).

    Google Scholar 

  61. Hodges, J. S. & Reich, B. J. Adding spatially-correlated errors can mess up the fixed effect you love. Am. Stat. 64, 325–334 (2010).

    Google Scholar 

  62. Rabus, B., Eineder, M., Roth, A. & Bamler, R. The shuttle radar topography mission—a new class of digital elevation models acquired by spaceborne radar. ISPRS J. Photogramm. Remote Sens. 57, 241–262 (2003).

    Google Scholar 

  63. Kuhn, M. et al. caret: Classification and regression training. R package version 6.0-77 (2018).

  64. De Reu, J. et al. Application of the topographic position index to heterogeneous landscapes. Geomorphology 186, 39–49 (2013).

    Google Scholar 

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We thank the New South Wales Government’s Department of Planning, Industry & Environment for providing funds to support this research via the NSW Bushfire Risk Management Research Hub.

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Authors and Affiliations



D.M.J.S.B. conceptualized and directed the the study and led the writing. G.J.W. undertook the analyses, produced the visualization and contributed to the writing. R.K.G. prepared data and contributed to the analysis and writing. R.A.B. and R.J.K. contributed to the writing and analysis.

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Correspondence to David M. J. S. Bowman.

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Extended data

Extended Data Fig. 1 Marginal effect of topographic position index (TPI) in fire severity for the three study regions.

Marginal effect of topographic position index (TPI) in fire severity for the three study regions.

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Bowman, D.M.J.S., Williamson, G.J., Gibson, R.K. et al. The severity and extent of the Australia 2019–20 Eucalyptus forest fires are not the legacy of forest management. Nat Ecol Evol 5, 1003–1010 (2021).

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