The latest IPCC report was approved on Sunday, 27 February 2022, by 195 member governments of the IPCC, including Australia.
CSIRO's published science across our research domains has contributed to the latest report, which includes a chapter on climate change impacts, risk and adaptation for Australia and New Zealand.
The chapter notes that climate risks are projected to increase for a wide range of systems, sectors and communities, exacerbated by underlying vulnerabilities and exposures.
Expert commentary by CSIRO contributors to the report
Talking on climate change trends and key risks discussed in the report, Mr Kevin Hennessy, lead author and contributing author for CSIRO Oceans and Atmosphere says:
"Ongoing climate trends have affected many extreme events. The Australian trends include further warming and sea-level rise, with more hot days and heatwaves, less snow, more rainfall in the north, less April-October rainfall in the south-west and south-east, and more extreme fire weather days in the south and east. Extreme events include Australia's hottest and driest year in 2019 with a record-breaking number of days over 39oC, three widespread marine heatwaves during 2016-2020, three major floods in eastern Australia during 2019-2021, and major fires in southern and eastern Australia during 2019-2020.
"Ongoing warming is projected, with more hot days and fewer cold days, further sea-level rise, ocean warming and ocean acidification. Less winter and spring rainfall is projected in southern Australia, with more winter rainfall in Tasmania, less autumn rainfall in south-western Victoria and less summer rainfall in western Tasmania, and uncertain rainfall changes in northern Australia. More droughts and extreme fire weather are projected in southern and eastern Australia. Increased heavy rainfall intensity is projected, with fewer tropical cyclones and a greater proportion of severe cyclones.
"We found nine key risks. They include loss of coral reefs, kelp and alpine biodiversity, possible collapse of some forests in southern Australia, damage to low-lying coastal areas, a decline in agricultural production in southern and eastern Australia, an increase in heat-related deaths, cascading impacts for cities and infrastructure due to extreme events, and the inability of institutions and governance systems to manage climate risks.
"Adaptation progress across the globe is uneven, due to gaps, barriers and limits to adaptation.
"The good news is that a range of incremental and transformative adaptation options and pathways is available. These include co-ordinating our resilience plans and decisions across all levels of government, industry and community. Key enablers include proactive planning, integration and coordination across all sectors, with nationally consistent and accessible information, decision-support tools, adaptation funding and finance."
Talking on water management and flooding implications, Dr Francis Chiew, lead author, Senior Principal Research Scientist (Hydrologist), CSIRO Land and Water says:
"The projected decline in future winter and spring rainfall in south-eastern Australia will be amplified in the decline in water resources. This will continue to exacerbate the already complex challenges of managing water for competing demands in this important region of Australia.
"The future in the Murray-Darling Basin will be hotter and drier, but there is considerable uncertainty around how much and by when, compounding the management and adaptation challenges. The Murray-Darling Basin a highly variable system, and we'd continue to see long wet periods and dry periods, but climate change will increase the frequency of droughts that people, and the ecosystems, need to cope with and recover from.
"The impacts of droughts over the recent decades, and projections of a drier future, have accelerated significant water policy reforms in particular the Basin Plan. These are positive adaptations as they help buffer the system against drought. But they can also be maladaptive by perpetuating unsustainable water and land use under ongoing climate change. In any case, more will need to be done, with the projected decline in water resources being potentially greater than the water recovered for the environment.
"High extreme rainfall will become more intense under a warmer climate. This will increase flood risk in cities, in built-up urban areas, and in small catchments, where the high rainfall can quickly become flash pluvial floods. There are good examples of adaptation to changing flood risk, and they are mostly reactive and incremental in response to floods and heavy rainfall events.
"Recent initiatives like the Australian Climate Services, the National Recovery and Resilience Agency and Drought Resilience initiatives, are positive steps to helping address risks from floods, fires, droughts and other hazards. These are important because of the cascading and aggregated impacts from multiple hazards on people, infrastructure, services and supply chains."
Talking on climate change implications on food and fibre, Dr Uday Nidumolu, Principal Scientist, Agriculture and Food says:
"Australian crop yields are projected to decline due to hotter and drier conditions, including intense heat spikes. Interactions of heat and drought could lead to even greater losses than heat alone.
"Across all types of agriculture, drought and its physical flow-on effects have caused financial and emotional disruption and stress in farm households and communities. To manage drought, balancing near-term needs with long-term adaptation to increasing aridity is essential.
"Australian farmers, who are among the foremost risk managers globally, are adapting to drier and warmer conditions through more effective capture of non-growing season rainfall like stubble retention to store soil water, improved water use efficiency, and matching sowing times and cultivars to the environment to manage climate risk for their production.
"Australian farmers are also adapting to changing climate through application of new technologies that improve resource efficiencies, professional knowledge and skills development, new farmer and community networks, and diversification of business and household income."
"CSIRO has been contributing to climate change adaptation through contributing to improved understanding and communicating climate-based risks in forest and agricultural systems; delivering climate-smart solutions for grains and other sectors including enhanced weather and seasonal climate forecasting; building risk and reward information tools that combine climate, systems modelling and environmental data for farmers and agribusiness; On farm – improving water use efficiency in broad acre farming; developing and testing strategies to improve productivity and profit-risk outcomes for growers; Long coleoptile genetics to improve wheat establishment with deep sowing to access out of season rain among many other initiatives.
"CSIRO makes significant contributions to this area of work overseas as well (South – South-east Asia, Pacific Island countries in particular) working with Australian Government agencies such as Australian Centre for International Agricultural Research, Australian Water Partnership among others, sharing Australian expertise in managing climate risk in agriculture."
The IPCC reports can be accessed at IPCC — Intergovernmental Panel on Climate Change (www.ipcc.ch). This includes a Summary for Policymakers, Technical Summary, 18 chapters, and 11 factsheets.
A report from Working Group III AR6 Climate Change 2022: Mitigation of Climate Change is scheduled for release in late March 2022.
A Synthesis report, combining assessments in Working Groups I, II and III, will be the final of the Sixth Assessment Report products and is due for release in September 2022. The synthesis report will provide an overview of the state of knowledge of climate change – integrating findings from the physical sciences, adaptation and mitigation reports.
