How do we measure disaster risk?

How do we measure disaster risk?

Identifying, assessing and understanding disaster risk is critical to reducing it.

We can measure disaster risk by analysing trends of, for instance, previous disaster losses. These trends can help us to gauge whether disaster risk reduction is being effective. We can also estimate future losses by conducting a risk assessment.

A comprehensive risk assessment considers the full range of potential disaster events and their underlying drivers and uncertainties. It can start with the analysis of historical events as well as incorporating forward-looking perspectives, integrating the anticipated impacts of phenomena that are altering historical trends, such as climate change. In addition, risk assessment may consider rare events that lie outside projections of future hazards but that, based on scientific knowledge, could occur. Anticipating rare events requires a range of information and interdisciplinary findings, along with scenario building and simulations, which can be supplemented by expertise from a wide range of disciplines.

Data on hazards, exposures, vulnerabilities and losses enhance the accuracy of risk assessment, contributing to more effective measures to prevent, prepare for and financially manage disaster risk (OECD, 2012). Modern approaches to risk assessment include risk modelling, which came into being when computational resources became more powerful and available (GFDRR, 2014a). Risk models allow us to simulate the outcomes and likelihood of different events.

Risk assessments are produced in order to estimate possible economic, infrastructure, and social impacts arising from a particular hazard or multiple hazards (GFDRR, 2014b).