As reported in SoE 2011, climate change continues to be a global problem. A major development since the 2011 report has been international cooperation to address the global issue, with 195 countries, including Australia, agreeing to the Paris Agreement, which aims to limit the increase in global temperatures to 2 °C above pre-industrial levels. International climate science has also advanced significantly. The Intergovernmental Panel on Climate Change, in its Fifth Assessment Report, confirmed (with between 95 and 100 per cent certainty) that humans have been the dominant cause of increases in greenhouse gas concentrations since the 1950s (Stocker et al. 2013a).
As in SoE 2011, Australia’s greenhouse gas (GHG) emissions per person remain the largest of any country in the Organisation for Economic Co-operation and Development (OECD). However, emissions per person have decreased from 24.1 tonnes in 2011 to 22.2 tonnes in 2015. The energy sector continues to dominate GHG emissions, increasing from 74 per cent of net emissions in SoE 2011 to 76 per cent in 2015.
Since SoE 2011, the globe has experienced the hottest year on record (2015), and Australia has experienced its hottest year (2013). Since the 2011 La Niña that helped break the millennium drought, drought has re-emerged across large parts of Australia, especially western Queensland, northern New South Wales and western Victoria. The 2015 El Niño was associated with below average rainfall across large areas of eastern Australia.
Australian governments have continued to implement policies to reduce GHG emissions, and, in the 5 years since SoE 2011, 2 major federal programs have been established. In 2012, a cap-and-trade emissions trading scheme started. This included a carbon price and the Carbon Farming Initiative, which provided incentives to reduce emissions in the land sector. This was repealed in 2014 and replaced with the Australian Government’s Direct Action Plan, including the Emissions Reduction Fund, which continues to operate.
The climate change projections for Australia, which model how Australia’s climate is likely to evolve during the next century, are also new in SoE 2016. These projections suggest that mean temperatures and extreme temperatures are likely to increase, with more hot days and fewer cold days. Increased risk of heatwaves will lead to increased risk of wildfire incidence and health problems (heat stress). Other risks are longer droughts with greater geographic coverage, flooding from more intense storm activity, sea level rise leading to coastal damage, and loss of ecosystems.