EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Towards species-level forecasts of drought-induced tree mortality risk

Martin De Kauwe1, Manon Sabot2,3, Belinda Medlyn4, Andrew Pitman2,3, Patrick Meir5, Lucas Cernusak6, Rachael Gallagher4, Anna Ukkola2,3, Sami Rifai2,3, and Brendan Choat4
Martin De Kauwe et al.
  • 1University of Bristol, School of Biological Sciences, Bristol, United Kingdom of Great Britain – England, Scotland, Wales (
  • 2ARC Centre of Excellence for Climate Extremes, Sydney, NSW 2052, Australia
  • 3Climate Change Research Centre, University of New South Wales, Sydney, NSW 2052, Australia.
  • 4Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
  • 5School of Geosciences, The University of Edinburgh, Edinburgh, EH9 3FF, UK
  • 6College of Science and Engineering, James Cook University, Cairns, Qld 4814, Australia

Predicting species-level responses to drought at the landscape scale is critical to reducing future uncertainty in terrestrial carbon and water cycle projections. We embedded a stomatal optimisation model in the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model. We parameterised the model for 15 canopy dominant eucalypt tree species representative of a broad precipitation gradient across South East Australia (mean annual precipitation range: 344–1424 mm yr-1). We conducted three experiments: (i) applying CABLE to the 2017–2019 drought in South East Australia; (ii) a 20% drier drought; and (iii) a 20% drier drought with a doubling of atmospheric carbon dioxide (CO2). We identified several drought hotspots across the ranges of E.viminalis, E.obliqua, E.globulus, E.saligna, and E.grandis. By contrast, CABLE simulated drought resilience in species that are found predominately in semi-arid areas such as E.largiflorens and E.populnea. We identified several key model assumptions (e.g., the degree of stomatal control) and sensitivities (e.g., the role of CO2 in ameliorating drought) that require future research. Our results represent an important step forward in our capacity to forecast the resilience of individual tree species, providing an evidence base for decision-making around the resilience of restoration plantings or strategies associated with achieving net-zero emissions.

How to cite: De Kauwe, M., Sabot, M., Medlyn, B., Pitman, A., Meir, P., Cernusak, L., Gallagher, R., Ukkola, A., Rifai, S., and Choat, B.: Towards species-level forecasts of drought-induced tree mortality risk, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2419,, 2022.