this was from old page - assessimgn coastal cliamte risks as a local scale

Climate change is already affecting Australia’s coasts, communities, infrastructure and ecosystems. Observed impacts include rising sea levels, increasing coastal inundation risk, coastal erosion, more intense rainfall, marine heatwaves and compound extreme events.

These combine to increase the likelihood of impacts on community health and wellbeing, loss or degradation of coastal ecosystems, disruption to essential services, damage to public and private assets etc.

Climate change risk assessment helps organisations understand what could be affected, how, and when, so they can make informed, defensible decisions about adaptation. For local governments and other place-based organisations, it provides a structured way to move from general awareness of climate change to clear priorities for action.

Risk assessment does not remove uncertainty, nor does it predict the future. Instead, it supports better decisions under uncertainty by identifying what matters most, where vulnerabilities lie, and which risks warrant further investigation or action.

In a climate change context, risk refers to the potential for adverse consequences where something of value is at stake and the outcome is uncertain. In climate science (i.e., IPCC 2022), risk arises from the interaction between hazards, exposure and vulnerability, and is shaped by the adaptive capacity of affected systems.

Risk arises from the interaction of four key elements:

• hazard – a climate-related event or trend that may cause harm, such as coastal inundation, erosion, heatwaves or extreme rainfall.
• exposure – the people, assets, services or ecosystems that are located where a hazard may occur.
• Vulnerability – the propensity of those exposed elements to be harmed, influenced by sensitivity and the capacity to cope or adapt.
• Adaptive capacity – the ability of a system, organisation or community to adjust to climate change, reduce potential damage or manage consequences.

Vulnerability and adaptive capacity are not fixed and may change over time due to social, economic, environmental or governance factors. Vulnerability is influenced by both sensitivity and adaptive capacity, meaning that vulnerability and adaptive capacity can change over time due to social, economic, environmental or governance factors.

Risk is often expressed by considering both the likelihood of a hazard occurring and the consequences if it does. For example, a low-lying coastal road may face increasing flood hazard as sea levels rise. If that road provides the only access to essential services, the consequences of disruption may be high, resulting in a high-risk rating.

Climate change can generate a wide range of risks that differ in timing, scale, pathways and severity.

Understanding these distinctions between these types of risks helps organisations avoid focusing only on immediate hazards and instead consider how climate risks may interact, evolve and intensify over time, progressively altering risk profiles over decades.

These risks can be understood in difference ways.

• Acute risks arise from discrete extreme events such as storm surge, flooding or heatwaves.
• Chronic risks develop gradually as climate conditions change, for example through sea-level rise or long-term shoreline erosion.

• Direct risks occur when climate hazards directly damage assets, infrastructure or ecosystems.
• Indirect risks arise through disruptions to interconnected systems, such as transport, energy water services, supply chains, economic activity or social systems.
• Climate risks can also interact. Compounding and cascading risks (also aggregate and protracted risks), occur when multiple hazards occur together, or when impacts in one system trigger consequences in another, amplifying overall impacts and potentially creating system-wide disruptions.

In addition to the above impact pathways, climate-related risks can be grouped into three broad categories that reflect the sources of risk faced by organisations and economies:

• Physical risks, resulting from the direct impacts of climate hazards (such as extreme weather events, sea-level rise or long-term changes in climate patterns).
• Transition risks, that arise from economic, technological, policy or social changes associated with the transition to a low-emissions economy.
• Liability risks, that may occur if organisations face legal or regulatory consequences for failing to adequately manage, disclose or respond to climate-related risks.

Climate change risks vary significantly from place to place. Local geography, coastal processes, land use, demographics, governance arrangements and economic activities all influence how hazards translate into impacts.

Local-scale risk assessment allows organisations to:

• account for place-specific characteristics and values
• understand how climate change interacts with existing local risks
• identify which communities, assets, services or ecosystems are most at risk
• support locally relevant adaptation decisions.

This differs from national or regional assessments, which are designed to inform policy directions and funding priorities rather than site-specific decisions. For councils and service providers, local-scale assessment is essential for practical planning and investment decisions

Not all risk assessments need the same level of detail. CoastAdapt uses a three-level approach that allows assessments to be proportionate to the decision being supported, the level of risk, and available resources.

First-pass risk assessment

A first-pass assessment is a rapid, low-cost screening that provides an overview of exposure to climate change risks. It typically uses readily available data and local knowledge to determine whether risks are likely to be significant and whether further assessment is warranted.

Second-pass risk assessment

A second-pass assessment follows a standard risk management approach, using national datasets, local information and expert judgement. It is commonly undertaken through structured workshops and results in a risk register that supports prioritisation of risks and identification of adaptation options.

Third-pass (detailed) risk assessment

A third-pass assessment is used where high-priority risks require more detailed investigation. It may involve targeted data collection, modelling or specialist studies to quantify impacts, define thresholds and inform major investment or engineering decisions.

Importantly, organisations do not need to progress automatically to the most detailed level. Many decisions can be supported effectively through first- or second-pass assessments.

A common misconception is that climate change risk assessment requires large volumes of high-resolution data. In practice, the data needs depend on the purpose of the assessment and the level of risk being explored.

• First- and second-pass assessments often rely on existing datasets, published projections and expert judgement.
• Detailed data and modelling are generally only required where decisions involve high-cost or irreversible actions.

Uncertainty is an inherent feature of climate change. Rather than attempting to eliminate uncertainty, good risk assessment makes assumptions explicit, explores plausible futures and avoids false precision.

Risk assessment helps organisations make robust decisions despite deep uncertainty about future climate conditions.

Risk assessment is a foundational component of adaptation planning, not a stand-alone activity. Within the CoastAdapt decision support framework (C-CADS), risk assessment supports the early stages of identifying challenges and assessing risks and vulnerabilities.

The outputs of a risk assessment tend to include priority risks and risk registers, which inform:

• identification of adaptation options
• sequencing of actions over time
• development of adaptation pathways
• monitoring and review as conditions change

Effective climate change risk assessment requires more than technical analysis. Common challenges include:

• over-scoping assessments beyond available resources
• focusing on hazards without considering consequences
• confusing risk assessment with risk treatment
• presenting overly complex results that are difficult to use in decision-making

Good practice involves being clear about purpose, keeping assessments proportionate, involving relevant expertise, and communicating results in a way that supports action.

• Climate change risk assessment supports informed decision-making under uncertainty.
• Risk arises from the interaction of hazard, exposure, vulnerability and adaptive capacity.
• Local-scale assessments are essential for practical adaptation planning.
• A tiered approach allows effort to be matched to risk and decision needs.
• Risk assessment is a starting point for adaptation, not an end in itself.