Sun et al. (2026) A New Vegetation Health Index Based on Vegetation Optical Depth: Development and Application in Vegetated Australia

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Geophysical Research Atmospheres
• Year: 2026
• Date: 2026-06-27
• Authors: Shanlei Sun, Aoge Ma, Qianxue Zu, Qianrong Ma, Yi Liu, Yibo Liu, Mengyuan Mu, Yang Zhou, Wenjian Hua, Botao Zhou, Haishan Chen
• DOI: 10.1029/2026jd046923

Research Groups

• Australian National University (ANU) Climate Science Centre
• Commonwealth Scientific and Industrial Research Organisation (CSIRO) Land and Water Division

Short Summary

This study develops a Vegetation Optical Depth (VOD)-based Vegetation Health Index (VHI) to improve vegetation drought monitoring in Australia, demonstrating its potential for representing vegetation conditions under changing hydroclimatic conditions.

Objective

• Investigate the limitations of the Normalized Difference Vegetation Index (NDVI) in accurately representing vegetation conditions and develop an alternative approach using VOD data.

Study Configuration

• Spatial Scale: National scale with a focus on vegetated areas across Australia.
• Temporal Scale: 1990–2024, divided into two sub-periods: 1990–2001 and 2002–2024.

Methodology and Data

• Models used: VOD data sets from multiple sources were integrated into the conventional VHI framework to develop the VHI VOD.
• Data sources: Long-term harmonized VOD data sets, Gross Primary Production, and soil moisture observations.

Main Results

• The VHI VOD outperformed the NDVI-based VHI across over 70% of vegetated Australia at both national and biome levels.
• A significant breakpoint occurred in 2002, with annual VHI VOD increasing during 1990–2001 but declining during 2002–2024.
• Weakening drought conditions were observed in both sub-periods, with over 70% of vegetated areas experiencing declines in severity, intensity, and duration.

Contributions

• The study provides an improved approach to vegetation drought monitoring using VOD data, addressing the limitations of NDVI-based methods.
• The findings highlight the potential of VHI VOD for representing vegetation conditions under changing hydroclimatic conditions.

Funding

• This research was supported by the Australian Research Council (ARC) and the CSIRO's Climate Adaptation Program.

Citation

@article{Sun2026New,
  author = {Sun, Shanlei and Ma, Aoge and Zu, Qianxue and Ma, Qianrong and Liu, Yi and Liu, Yibo and Mu, Mengyuan and Zhou, Yang and Hua, Wenjian and Zhou, Botao and Chen, Haishan},
  title = {A New Vegetation Health Index Based on Vegetation Optical Depth: Development and Application in Vegetated Australia},
  journal = {Journal of Geophysical Research Atmospheres},
  year = {2026},
  doi = {10.1029/2026jd046923},
  url = {https://doi.org/10.1029/2026jd046923}
}