March 13, 2020 | Published by | ,

Picture (above): Forest view near Albany, WA. Credit: Harry-Cunningham (Unsplash)

During the period from 1997 to 2009, Australia experienced a severe and persistent drought known as the Millennium Drought. Given uncertain projections of future drought conditions in South-East Australia, an analysis of the Millennium Drought presented a valuable opportunity to assess the possible impacts of these future trends.

In this study, CLEX researchers and colleagues analysed the magnitude and sensitivity of vegetation responses to the Millennium Drought with satellite-derived information including the fraction of photosynthetically absorbed radiation (FPAR), photosynthetic vegetation cover (PVC), canopy density derived from vegetation optical depth (VOD) and aboveground biomass carbon (ABC).

The analysis showed cultivated lands and grasslands experienced the most severe impacts of the Millennium Drought and showed the highest drought sensitivity.

Drought sensitivity of natural vegetation tended to increase from humid to arid settings whereas biomass saw decreased sensitivity.

This high drought sensitivity of aboveground biomass carbon in forest ecosystems indicates a sizeable risk of carbon release with future droughts.

  • Paper: Jiao, T., Williams, C. A., Rogan, J., Medlyn, B. E. and De Kauwe, M. G. (2020) Drought impacts on Australian vegetation during the Millennium Drought measured with multi-source spaceborne remote sensing. Journal of Geophysical Research: Biogeosciences, DOI: 10.1029/2019JG005145