Australia’s future terrestrial carbon sinks
Alison Bennett
1. Introduction and scientific context
Australia’s terrestrial carbon cycle is highly dynamic, responding to a broad range of climate modes and extremes, that are rapidly changing. It is critical to study the future evolution of Australia’s carbon sinks under a changing climate to determine their capacity to support Australia’s net-zero objectives and to identify optimal placement of nature-based solutions.
2. Methodology/project summary
We simulated Australia’s future terrestrial carbon cycle (2015 to 2100) under low (SSP1-2.6) and high (SSP3-7.0) emissions scenarios using the CABLE-POP land surface model, forced with climate projections from seven CMIP6 global climate models (GCMs). We examined changes in Net Biome Productivity (NBP) across the continent, between bioclimatic regions, and assessed the importance of climate and CO2 in influencing changes.
3. Results
Australia’s land will act as a carbon sink under SSP3-7.0 (2070-2099 mean: 0.12; range:-0.07 to 0.47 Pg C yr-1) but this is less certain under SSP1-2.6 (2070-2099 mean: 0.02; range:-0.22 to 0.31 Pg C yr-1) and if future climatic conditions are substantially drier than today. Declining rates of carbon uptake were consistently simulated for the southwest, southeast and east coast suggesting these regions be avoided for nature-based solutions. Interannual variability in NBP was predicted to increase, particularly in the sparsely-vegetated region, and precipitation predominantly influenced change in NBP.
4. Audience
Land-surface modellers, climate modellers, CABLE users, scientists and policy makers interested in net-zero and nature-based solutions
5. Keywords
Terrestrial carbon cycle, climate change, future, net-zero, CABLE, land surface model
Please use this thread for discussion about this plenary talk.