Mitigation to reduce emissions of greenhouse gases is the surest way to reduce the impacts of climate change. Even with strong mitigation, however, some impacts of climate change are inevitable and reducing them will require adaptation.

There are many adaptation options that will provide benefits in excess of their cost. Adaptation to climate change is essential to protect communities, infrastructure and the natural environment from damaging impacts. Failure to act places all of these at risk.

While the need to act on climate change is increasingly accepted, there are still barriers to action.

• Perceptions and beliefs: psychological factors can lead to denial or underestimation of risk.
• Knowledge gaps: lack of understanding about how to act.
• Cultural and institutional barriers: established norms and systems may resist change.
• Social and economic constraints: limited resources or competing priorities.
• Governance and policy limitations: inadequate frameworks or unclear responsibilities.

Doing nothing is not neutral: not responding to climate-related risks is itself a decision. Choosing inaction leaves people, infrastructure and natural systems exposed to harm and missed opportunities.

Taking no action does not stop climate change from happening or slow its effects; instead, it increases the exposure of communities, assets and ecosystems to known climate risks and can lock in future losses that are more difficult and expensive to address later. Here we discuss some of these risks.

A number of reports provide estimates on the high financial cost of climate inaction.

Climate inaction poses severe economic risks. Since 2000, climate-related disasters have caused over $3.6 trillion in damages: costs have more than doubled from 2022-2024 (World Economic Forum 2024).

In Australia;

• Economic losses of failing to act for Australia are estimated at A$129 billion per year (Hutley, 2021)
• Australia’s GDP could be reduced by A$6.8 trillion cumulatively (−14% annually between 2024–2050) if the transition to renewables is delayed (IGCC).

Costs are not only economic. Inaction will also lead to very high social costs.

For instance: Floods are one of the most damaging impacts of climate change and are projected to increase under a changing climate. Therefore, it is informative to look at the costs of these types of events.

A 2023 review of the 2022 Northern NSW floods highlights the social impacts, which included:

• loss of life and trauma: nine deaths in the Northern Rivers event (Feb–Mar 2022); total 2022 flood toll across eastern Australia was higher (e.g., 23 deaths)
• displacement and homelessness: over 14,500 homes were damaged, with more than 5,000 rendered uninhabitable; nearly 8,000 people were in emergency accommodation by July 2022; nearly 1400, still in emergency accommodation in August 2022.
• mental health: the Northern NSW region experienced enduring trauma: there was a spike in demand for mental health and wellbeing services
• primary care: operations were disrupted from weeks to months due to damaged infrastructure, loss of communication and utilities, and limited access to essential supplies

Without adaptation, further changes in climate are projected to have substantial impacts on the natural environment. Rising ocean temperatures, more frequent extreme events and sea-level rise will continue to degrade coastal habitats.

Without proactive measures that help ecosystems adapt climate change will drive fundamental ecological changes and loss of biodiversity. For example: Tasmania’s 2024 State of the Environment report found 16 out of 29 environmental categories worsening, including sea surface temperature increases (+2.5–3.8 °C since 1944), severe declines in kelp forests, and over 76 vertebrate species now threatened.

Furthermore, with every extinction there is not just a direct loss of species but a further loss of cultural traditions and connections as well as scientific insights.

Decision makers are required to consider the best possible knowledge in making decisions about adaptation to climate change. This implies that the knowledge should be up-to-date and from reputable scientific sources. 

Increasingly, there is a range of authoritative sources that can supply scientific information about the types of impacts projected, making it relatively simple to find information on projected climate impacts. These range from:

• international reports from the Intergovernmental Panel on Climate Change (IPCC)
• national reports such as the biannual release of the State of the Climate by CSIRO and Bureau of Meteorology
• state and local government reports from your relevant jurisdiction

Climate change litigation is increasing in volume, scope and scale, particularly since the Paris Agreement in 2015. Continuing advancements in the science of climate attribution is also considered to increase climate change litigation in Australia over the next few years.

As climate change progresses, and damaging impacts occur more frequently, insurance for property and assets will become difficult to obtain at reasonable prices.  There are already escalating insurance challenges, with climate change reshaping insurance markets:

• Premiums in coastal and flood-prone areas continue to rise as insurers price in increasing hazard frequency and severity, squeezing household budgets and in some cases making coverage unaffordable.
• Major insurers have called for government co-investment in risk reduction (e.g. a national Flood Defence Fund) because doing nothing is making insurance less affordable and less available.
• Without adaptation (e.g. strategic retreat, building standards upgrades, protective infrastructure), insurance pressures will reduce financial resilience.

While there are lots of negatives from climate change, there are also many opportunities that can be realised through proactive adaptation. For instance, some industries will find new resources or markets.

• In cooler climates, for example in Tasmania, it may become possible to grow crops that require warmer temperatures and a longer growing season than is currently experienced. For example, Tasmania viticulture has been adapting to climate change for decades and using is it to drive innovation.
• Warm-water commercial fish varieties may migrate into more southerly waters and be accessible to Australian near-shore fishing fleets.