There is now a consensus on climate change and its human causes¹. Multiple studies published in peer-reviewed scientific journals show that human activities are the primary cause of the observed climate-warming trend over the past century.

We know the earth is warming and that we now face inevitable change that can no longer be completely mitigated, with even the best-case scenario limiting the globe to an average 1.5 degree Celsius increase.

Climate science and data

The Intergovernmental Panel on Climate Change (IPCC) is currently in its 6th Assessment cycle and has recently released a series of working group reports based on the latest science, and  finalised the Synthesis Report in March 2023. It calls for immediate and rapid decarbonisation if we hope to limit global warming to 1.5 degree Celsius.

For South Australia, the State Government has partnered with NSW  in the "NSW and Australian Regional Climate Modelling" (NARCLiM) program. Led by the NSW Government in partnership with the ACT, SA and WA governments, and with contributions from UNSW and Murdoch University, regional projections will be expanded across Australia, becoming a product that can be used by governments, climate specialists in industry and researchers across Australia. Updated projections (NARCliM1.5) are now available, while NARCLiM2.0 will be based on the IPCC 6th assessment (AR6), and planned for release later in 2023.

Climate change projections

The Climate Change in Australia resource page presents past observational data from the Australian Bureau of Meteorology. Projections are focused on mid-century (2040-2059) relative to 1986-2005 (unless otherwise stated), in line with baselines used by the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5). Projections are based on a high emissions scenario (RCP8.5), and averages refer to the average of projected changes across the whole State.

South Australia is already experiencing the impacts of climate change.

1. All of South Australia has warmed since 1910. Average annual temperature has increased by 1.6 Celsius since 1910.
2. Since 1900, winter rainfall has declined and summer rainfall has increased over most of southern Australia. There has been a persistent decline in rainfall in the state’s southern agricultural areas².
3. The number of days with dangerous weather conditions for bushfires has increased across the region.

The climate of South Australia is projected to continue to change over the coming decades. By mid-century (2050), the following changes are projected³.

	Higher temperatures Warmer spring temperatures Hotter and more frequent hot days	Maximum, minimum and average temperatures will increase. Warming in spring is likely to be greater than in any other season. The frequency of very hot days will continue to increase, and periods of hot weather will get longer and hotter.
	Fewer frosts	The frequency of frost events will remain comparable until 2030. In the longer-term, frosts are expected to decrease as the climate warms.
	Declining rainfall Lower spring rainfall More drought	Average annual rainfall will decline. Spring rainfall declines will be greater than any other season. Time spent in drought will increase.
	More intense heavy rainfall events	The number and intensity of heavy rainfall events will increase.
	Increased potential evapotranspiration	Potential evapotranspiration is projected to increase across all seasons.
	Wind	Wind speeds will remain comparable until 2030. In the longer-term, a pattern of winter wind speed decrease is likely.
	More dangerous fire weather	Harsher fire weather will be experienced, and fuels will be drier and more ready to burn.
	Rising sea levels	Sea levels will continue to rise.
	Warmer and more acidic ocean waters	Sea surface temperatures will continue to rise, and acidity will continue to increase.

Further information of projected changes for temperature, rainfall, fire weather, and sea level, as well as detailed regional projections for Adelaide, Clare, Coober Pedy, Keith, Mount Gambier, Port Augusta, Renmark, Whyalla, Woomera and Wudinna, can be found in the South Australian Government's Guide to climate projections for risk assessment and planning in South Australia 2022.

Source

¹   The ‘97% climate consensus’ is over. Now it’s well above 99% (and the evidence is even stronger than that)

²  Tracking changes in South Australia’s environment – trend and conditions report cards 2018, Government of South Australia Department for Environment and Water

³ Guide to climate projections for risk assessment and planning in South Australia 2022