Drought under climate change
See how the NSW Combined Drought Indicator could look by mid to the end of the current century.
The Climate Vulnerability Assessment looked at the impacts of climate change on 38 commodities and biosecurity risks. An important element of understanding the impacts and risks associated with climate change on primary industries is understanding how drought frequency and duration will change as a result of global warming. Drought has a significant impact on the annual productivity of land based primary industries and causes significant regional economic stress when prolonged drought occurs.
Assessing the duration and frequency of droughts is complicated because there are many factors that contribute to drought conditions. Normal seasonal variations, annual and shorter-range variability in climate drivers and local weather systems, as well as the agricultural landscape all interact to give a region its drought footprint.
How a region’s drought footprint will evolve as global temperatures warm in the coming decades adds to this complexity. The scientific community have advised for over two decades that there is likelihood that the nature of drought events will change going forward.
Summary of findings
Finding 1: Adverse changes to future drought characteristics across most of NSW
Under the intermediate greenhouse gas emissions scenario (SSP245) in the medium-term future (2050), drought events are likely to be 50-200 days longer. There will also tend to be 1-3 more events over a 20-year management window, and the time spent in drought will likely increase by 10-20 percent for much of the state.
Finding 2: Limited change to drought characteristics in some NSW regions
The generally adverse scenarios described above do not hold for all regions of the state. Even in the far future (2090) and under the high emissions scenario, drought characteristics are likely to remain unchanged or may improve slightly for some parts of NSW.
Finding 3: Global Climate Model quality assessment is important at a regional level
Local level (farm to regional) drought projections can vary dramatically when the ability of climate models to track recent drought history is included in the assessment.
These findings are provided with a medium level of confidence. They are consistent with previous studies of drought in a changing climate completed for Australia, where the nature of future droughts shifts towards greater risk. Like these studies, this work has distinct limitations, and it is important for readers to review and consider these in the main report.
Download the full report here.
