Australia Climate Resilience Policy Indicator

Temperature

Australia’s weather and climate continue to change at the same time as the global climate becomes warmer. Its average temperature has increased by 1.47 ± 0.24°C since national record-keeping began in 1910, with most warming occurring since 1950 and every decade since then being warmer than the previous one. Temperature rise has affected the entire country and all seasons, and in the past two decades the warming rate was more than 0.042°C per year (+0.011°C above the world average), increasing the number of cooling degree days (CDDs) and reducing heating degree days (HDDs). Australia’s warmest year on record was 2019, and the seven years from 2013 to 2019 were among the top nine warmest ones. This long-term warming trend means that most years are now warmer than almost any in the 20th century.

Rising temperatures are also accompanied by an increase in the number of extremely warm days, which totalled 43 in 2019 – more than triple the number in any year before 2000. The number of days with a national daily average maximum temperature higher than 39°C was 33 in 2019, which exceeds the combined total of 24 days recorded from 1960 to 2018. Plus, Australia’s temperature is likely to continue rising.

Extreme heat is considered one of the greatest stresses on Australia’s energy systems, since it affects energy demand and supply simultaneously. High temperatures could not only spur cooling-load increases but reduce electricity network capacity, decreasing thermal generation ratings and causing equipment failures. For instance, the combination of high electricity demand and lower electricity supply availability caused by extreme heat in South Australia and Victoria on 24-25 January 2019 prompted load-shedding, which left 200 000 people without access to electricity.

Nevertheless, some cooler years do occur due to Australia’s inherently high climate variability, mostly resulting from natural climate drivers such as El Niño and La Niña in the tropical Pacific Ocean and phases of the Indian Ocean Dipole. As Australia’s general warming trend is additional to its pre‑existing natural climate variability, it can modify the impact of these regional influences on the country’s climate.

Precipitation

Average precipitation has decreased in the past two decades, although above-average rainfall was recorded in some years owing to other natural causes (such as La Niña in 2010-2011). The overall decrease results mainly from a significant drop in April to October precipitation in Southern Australia, despite an increase in northern regions. May to July rainfall in southwestern Australia has decreased the most – by around 20% since 1970.

Long-term rainfall reductions across southern Australia also threaten water availability. Three-quarters of hydrologic reference stations around Australia have recorded declining streamflow trends, increasing the risk of droughts. Australia’s climate model (ACCESS) therefore projects that Australia will spend more time in drought in upcoming decades due to lower cool-season rainfall.

Furthermore, the combination of increasing dryness and rising temperatures could intensify the probability of wildfires. The number of fire weather days has increased in recent decades, especially in southern and eastern Australia, and the fire season has become longer. Indeed, in December 2019 when the fire weather index was the highest on record, wildfires were burning throughout New South Wales and Victoria. Wildfires in 2019-2020 caused unplanned power outages, mainly because flames damaged transmission and distribution lines. In New South Wales alone, the two main electricity suppliers reported the destruction of 4 000 power poles, leaving 158 000 people without electricity. Australia’s fire weather season is projected to begin earlier, and fire weather days are expected to become more frequent. In fact, in southern and eastern Australia, the frequency of fire-conducive days may increase by up to 30% by 2050.

Despite an overall increase in dryness and declining precipitation, the intensity of heavy rainfall events in Australia has risen by over 10% in some regions in recent decades. As the climate warms, heavy rainfalls are expected to become more intense because a warmer atmosphere can hold more water vapour than a cooler one. The possibility of flash flooding is also expected to increase, which may damage energy infrastructure in flood-prone areas.

Tropical cyclones and storms

Tropical cyclone activities vary substantially from year to year.1 Although Australia is expected to experience fewer in upcoming decades, more of them are projected to be of high intensity. Intense tropical cyclones may threaten the country’s energy supply by causing physical damage to energy infrastructure and assets. For instance, tropical cyclone Seroja, which hit Australia’s west coast in April 2021, cut electricity to over 30 000 people.

In 2012, the then Council of Australian Governments (COAG), consisting of representatives from all Australian governments, agreed on climate change adaptation roles and responsibilities for each level of government. All levels of government, businesses, communities and individuals have important differentiated but complementary roles in adapting to the impacts of climate change. In line with these responsibilities, all levels of government have plans to adapt to climate change.

In 2021, the Australian Government released its new National Resilience and Adaptation Strategy 2021-2025, building on the first Strategy of 2015. The new Strategy’s three objectives to enable more effective adaptation across Australia are to: drive investment and action through collaboration; improve climate information and services; and assess progress and improvements. The Strategy’s goal is to help governments, communities and businesses adapt effectively to climate change, recognising that adaptation is a shared responsibility that requires sustained action.

The Strategy aims to advance climate change adaptation in the natural, built, social and economic domains. While it considers the energy sector as part of the built environment, some state-level plans prescribe actions specific to energy sector climate resilience (e.g. Queensland’s Built Environment and Infrastructure Sector Adaptation Plan). The National Adaptation Policy Office (NAPO) is responsible for co‑ordinating adaptation advice for all industries and governments to implement the new National Resilience and Adaptation Strategy.

Australia’s first Adaptation Communication also includes examples of energy sector adaptation and resilience actions taken domestically at all levels of government, as well as action abroad.

In the broader context of natural disaster resilience, the Australian Government established a Royal Commission into National Natural Disaster Arrangements in 2020 and a National Recovery and Resilience Agency in 2021. The Agency supports communities impacted by disasters such as floods, bushfires, cyclones and droughts, combining expertise in natural disaster response, recovery and resilience. Australia’s government has also introduced an overarching Critical Infrastructure Resilience Strategy with its accompanying laws and regulations. It broadly aims to fortify energy system resilience to potential threats, including natural disasters, cyber-attacks and other human and environmental hazards.

Although Australia’s national plans on energy (e.g. the Energy White Paper, the National Energy Productivity Plan 2015-2030 and the 2021 Australian Infrastructure Plan) do not feature climate change adaptation and energy sector resilience as focus areas, their proposed actions (e.g. improved energy efficiency of buildings) may consequently enhance climate resilience regardless of the primary objectives.

Some states have incorporated climate considerations into state-level energy and infrastructure plans. For instance, the State of New South Wales’s 2018 Critical Infrastructure Resilience Strategy recognises that climate change is a challenge to infrastructure resilience and covers various aspects of the energy sector, such as the electricity grid.

Ongoing efforts also address the adverse impacts of climate change at the sectoral level. For instance, the Integrated System Plan (ISP) for the National Electricity Market is a biennial publication released in 2018 and updated in 2020 by the Australian Energy Market Provider (AEMO) to identify the optimal development path for the National Electricity Market. By considering vulnerabilities and climate factors (including temperature, irradiance, wind and dam inflow projections and the frequency and severity of extreme weather events), it proposes actions to enhance energy system resilience. To make the electricity market more climate-resilient, it suggests concrete measures such as incorporating climate change trends into energy system planning and exploring implications of extreme weather events. The Draft 2022 ISP was published in December 2021 and is under consultation.

Climate information and tools to support such plans are well established in Australia, with national science institutions providing many of them. In fact, the Australian Government established the Australian Climate Service on 1 July 2021 to gather Australia’s extensive climate and natural hazard data and socioeconomic information together in one place to make it easier to anticipate and adapt to climate change impacts. The Australian Climate Service draws on world-leading expertise from its four partner agencies: the Bureau of Meteorology, Geoscience Australia, the Commonwealth Scientific and Industrial Research Organisation (CSIRO), and the Australian Bureau of Statistics (ABS).

CSIRO, a government research agency, supports the Australian government by producing in-depth climate change analyses and developing emergency situation awareness software to help manage natural disaster impacts.

In addition, the national government funds the collection of new information and database development. For instance, the Climate Change in Australia website presents a number of climate change projections for the country and hosts the Australian Climate Futures tool, which provides regional climate projections for impact assessment and adaptation planning. The government also funded the Electricity Sector Climate Information (ESCI) project to help electricity sector decision makers enhance resilience to extreme weather events. These climate databases and tools could provide the foundation for a national-level plan on energy sector climate resilience, laying out future steps for national energy sector climate resilience as well as guiding and accelerating co‑ordinated interstate action.