Quantifying catastrophic and climate impacted hazards based on local expert opinions

Area of Science:

• Environmental Science
• Risk Management
• Climate Change Adaptation

Background:

• Quantifying catastrophic and climate-impacted hazards presents significant challenges due to high damage and uncertainty.
• Local areas often lack sufficient data on rare extreme events to accurately model frequency and severity distributions.

Purpose of the Study:

• To discuss and illustrate a method for quantifying catastrophic risks using local assessments and expert elicitation.
• To enable local government decision-makers to better estimate and manage the severity distribution of climate-impacted hazards.

Main Methods:

• Utilizing expert elicitation to obtain distribution parameters for rare extreme events.
• Employing heavy-tailed distributions to model the severity of climate-impacted hazards.
• Requiring local experts to specify two percentiles of the loss distribution for severity estimation.

Main Results:

• Demonstrated a simple approach for estimating severity distribution parameters using limited local data.
• Applied the method to quantify property losses from bushfires in a specific local area.
• Showcased the impact of variables like discount rates, climate change, and adaptation on loss estimates.

Conclusions:

• The proposed expert elicitation method provides a practical way to estimate parameters for extreme event severity distributions.
• This approach supports local decision-making in quantifying and managing catastrophic risks associated with climate change.
• The method effectively focuses on extreme losses and the tail of the distribution, crucial for effective risk management.