Lesson 2：Six steps of disaster risk assessment

Summary

This lesson covers the critical steps involved in disaster risk assessment, particularly for compound and cascading hazards. It introduces a six-step process: hazard analysis, exposure assessment, vulnerability assessment, risk mapping, risk scenario development, and resources and capacity mapping. The course explains how to assess complex hazards, considering their spatial and temporal dimensions, and the expanded scope of risk due to cascading impacts. By identifying hazards, vulnerable elements, and available resources, communities can better prepare for disasters. The lesson provides practical tools and examples, helping learners understand the importance of comprehensive risk assessment in disaster management.

Takeaways

• 😀 The risk assessment process for compound and cascading disasters is more complex than for single hazards, requiring additional steps to assess interconnected risks.
• 😀 The six-step process for disaster risk assessment includes: hazard analysis, exposure assessment, vulnerability assessment, risk mapping, scenario development, and resource/capacity mapping.
• 😀 Hazard analysis examines spatial and temporal patterns of compound and cascading hazards, which can impact local, national, and even global areas.
• 😀 Exposure assessment involves identifying which people, infrastructure, or assets are at risk from potential hazards, expanding the scope to include critical infrastructure and global supply chains.
• 😀 Vulnerability assessment evaluates how susceptible a community or asset is to disaster impacts, considering both tangible and intangible damage.
• 😀 Risk mapping visualizes the relationship between hazards, exposure, and vulnerability, categorizing areas into high, medium, or low risk levels.
• 😀 Risk scenarios describe potential future disaster events, showing how hazards can interact and create cascading impacts. These scenarios help with future planning.
• 😀 Climate change must be factored into hazard assessments, as it can alter the frequency, intensity, and seasonality of hazards, making historical data alone insufficient.
• 😀 Vulnerability is closely linked to a community's capacity to respond and recover, and understanding these capacities is key to reducing damages.
• 😀 Resource and capacity mapping helps identify gaps in available resources and readiness, ensuring that a community can respond effectively to disasters.
• 😀 A multi-layered hazard map, like the one used in Japan, helps stakeholders visualize multiple disaster risks in a given area, though it should also include technological and biological hazards for a comprehensive approach.

Q & A

What is the main objective of the course presented by Eric Zussman?

The main objective of the course is to discuss how to add the concept of compound and cascading disasters into the risk assessment process, helping communities better understand and manage the risks associated with such disasters.

How does risk assessment differ between single disasters and compound or cascading disasters?

Risk assessment for single disasters focuses on analyzing a single hazard event, whereas compound or cascading disasters require a more complex assessment due to their interconnected nature, considering how multiple hazards interact and affect each other over time and space.

What are the six key steps in assessing risks from compound and cascading disasters?

The six key steps are: 1) Hazard analysis, 2) Exposure assessment, 3) Vulnerability assessment, 4) Risk assessment and mapping, 5) Risk scenario development, and 6) Resources and capacity mapping.

What is hazard analysis, and why is it crucial in assessing compound and cascading disasters?

Hazard analysis involves identifying and understanding the spatial and temporal patterns of hazards. It's crucial because compound and cascading hazards can evolve in complex ways, and recognizing these patterns helps in managing responses more effectively.

What are the three spatial patterns of multi-hazards mentioned in the course?

The three spatial patterns are: 1) Local origin, where hazards occur at the local level and might spread regionally or globally; 2) External origin, where hazards originate at a distant location and impact local areas; 3) Distributed or complex origins, where multiple hazards occur at different locations and interact in complex ways.

How does temporal dimension impact the assessment of compound and cascading disasters?

The temporal dimension refers to the timing, seasons, or years in which hazards occur. Different hazards manifest at different times, such as floods during the rainy season or wildfires during the dry season. Understanding this helps identify patterns of cascading impacts over time.

What role does climate change play in hazard assessment?

Climate change significantly affects hazard patterns, making it impossible for communities to rely solely on historical data. Tools like ImpactViewer and Climocast are useful in assessing the impact of climate change on hazards.

What is the difference between exposure and vulnerability in disaster risk assessment?

Exposure refers to the presence of people, infrastructure, or assets that could be affected by a hazard, while vulnerability is the degree to which these elements are susceptible to damage, considering their ability to recover and respond.

How did the 2018 disaster in Okayama, Japan illustrate the concept of exposure and vulnerability?

In Okayama, Japan, the factory's location near a river made it vulnerable to flooding, which contributed to the explosion when the heavy rain caused river overflow. The exposure included the factory, people, and infrastructure, while vulnerability was related to the inadequate response capacity to deal with the compounded disaster.

What is the purpose of developing risk scenarios in the context of disaster risk assessment?

Risk scenarios are used to describe potential future events and their outcomes. They help communities visualize how cascading hazards may unfold and allow for better planning, resource allocation, and risk reduction strategies.