Modelling pathways to inform Australia’s 2035 Nationally Determined Contribution 

In 2025, CSIRO was commissioned by the Climate Change Authority to support the development of Australia’s 2035 Nationally Determined Contribution (NDC) and inform the country’s broader net-zero emissions by 2050 strategy. The work responded to a parliamentary request for a comprehensive assessment of emissions reduction pathways across six major sectors: electricity and energy, transport, industry and resources, land and agriculture, waste, and the built environment. 

The analysis explored alternative decarbonisation pathways under different global climate contexts, including a world limiting warming to below 2°C and a more ambitious 1.5°C pathway. Within these global scenarios, multiple domestic pathways were assessed reflecting different levels of Australian ambition, including net-zero timelines ranging from 2050 to 2035. Additional sensitivity analyses tested the resilience of the energy system under constraints on renewable energy deployment. 

A multi-model framework was used to assess interactions between energy systems, the economy, and land use. Results show that the pace and scale of emissions reductions depend strongly on both domestic policy ambition and global transition dynamics. The analysis highlights the central role of rapid electricity decarbonisation, large-scale deployment of low-emissions technologies across sectors, and contributions from land-sector sequestration and negative emissions options in achieving more ambitious targets.