Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Impacts of the 2019–2020 Black Summer Drought on Eastern Australian Forests

Arampola, Nuwanthi LU ; Medlyn, Belinda ; Hislop, Samuel ; Choat, Brendan ; Olin, Stefan LU ; Mansourian, Ali LU orcid ; Zhao, Pengxiang LU and Smith, Benjamin LU (2025) In Remote Sensing 17(5).
Abstract

Droughts present a significant global challenge, particularly to forest ecosystems in regions such as eastern New South Wales, Australia, which is known for its dry climate and frequent, intense droughts. Recent studies have indicated a notable increase in tree mortality and canopy browning across this area, especially during the recent extreme drought period culminating in the Black Summer of 2019–2020. Our study investigates the impacts of drought on eucalypt forests by leveraging remote sensing and field observation data to detect and analyse vegetation health and stress indicators. Utilising data from Sentinel-2, alongside historical Landsat observations, we applied multiple spectral vegetation indices, namely the Normalized... (More)

Droughts present a significant global challenge, particularly to forest ecosystems in regions such as eastern New South Wales, Australia, which is known for its dry climate and frequent, intense droughts. Recent studies have indicated a notable increase in tree mortality and canopy browning across this area, especially during the recent extreme drought period culminating in the Black Summer of 2019–2020. Our study investigates the impacts of drought on eucalypt forests by leveraging remote sensing and field observation data to detect and analyse vegetation health and stress indicators. Utilising data from Sentinel-2, alongside historical Landsat observations, we applied multiple spectral vegetation indices, namely the Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), Normalized Burn Ratio (NBR), and Tasseled Cap Transformation, to assess the extent of drought impacts. We found NBR to show the most consistent agreement with ground-based observations of drought-related tree mortality. Additionally, by integrating ground-based data from the “Dead Tree Detective” citizen science project, we were able to validate the remote sensing outcomes with a 90.22% consistency, providing confirmation of the extensive spatial distribution and severity of the inferred impacts. Our findings reveal that 13.16% of eucalypt forests and woodlands across eastern New South Wales experienced severe stress associated with drought during the 2019–2020 Black Summer drought. This study demonstrates the utility of satellite-derived drought indicators in monitoring forest health and highlights the necessity for continuous monitoring and research to understand the factors that trigger tree vitality loss.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Drought, Bioregions, Canopy Health Score, Tree browning, Eucalypt forests and woodlands, Mortality, Remote sensing, Climate Change
in
Remote Sensing
volume
17
issue
5
article number
910
pages
26 pages
publisher
MDPI AG
external identifiers
  • scopus:86000763644
ISSN
2072-4292
DOI
10.3390/rs17050910
language
English
LU publication?
yes
additional info
Publisher Copyright: © 2025 by the authors.
id
ca1448ea-3fa3-442a-a085-8fa2d1a6972a
date added to LUP
2025-05-07 09:55:31
date last changed
2025-05-08 14:37:11
@article{ca1448ea-3fa3-442a-a085-8fa2d1a6972a,
  abstract     = {{<p>Droughts present a significant global challenge, particularly to forest ecosystems in regions such as eastern New South Wales, Australia, which is known for its dry climate and frequent, intense droughts. Recent studies have indicated a notable increase in tree mortality and canopy browning across this area, especially during the recent extreme drought period culminating in the Black Summer of 2019–2020. Our study investigates the impacts of drought on eucalypt forests by leveraging remote sensing and field observation data to detect and analyse vegetation health and stress indicators. Utilising data from Sentinel-2, alongside historical Landsat observations, we applied multiple spectral vegetation indices, namely the Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), Normalized Burn Ratio (NBR), and Tasseled Cap Transformation, to assess the extent of drought impacts. We found NBR to show the most consistent agreement with ground-based observations of drought-related tree mortality. Additionally, by integrating ground-based data from the “Dead Tree Detective” citizen science project, we were able to validate the remote sensing outcomes with a 90.22% consistency, providing confirmation of the extensive spatial distribution and severity of the inferred impacts. Our findings reveal that 13.16% of eucalypt forests and woodlands across eastern New South Wales experienced severe stress associated with drought during the 2019–2020 Black Summer drought. This study demonstrates the utility of satellite-derived drought indicators in monitoring forest health and highlights the necessity for continuous monitoring and research to understand the factors that trigger tree vitality loss.</p>}},
  author       = {{Arampola, Nuwanthi and Medlyn, Belinda and Hislop, Samuel and Choat, Brendan and Olin, Stefan and Mansourian, Ali and Zhao, Pengxiang and Smith, Benjamin}},
  issn         = {{2072-4292}},
  keywords     = {{Drought; Bioregions; Canopy Health Score; Tree browning; Eucalypt forests and woodlands; Mortality; Remote sensing; Climate Change}},
  language     = {{eng}},
  number       = {{5}},
  publisher    = {{MDPI AG}},
  series       = {{Remote Sensing}},
  title        = {{Impacts of the 2019–2020 Black Summer Drought on Eastern Australian Forests}},
  url          = {{http://dx.doi.org/10.3390/rs17050910}},
  doi          = {{10.3390/rs17050910}},
  volume       = {{17}},
  year         = {{2025}},
}