AGU News:

In recent decades, a striking number of countries have suffered from consecutive disasters: events whose impacts overlap both spatially and temporally, while recovery is still under way.

The risk of consecutive disasters will increase due to growing exposure, the interconnectedness of human society and the increased frequency and intensity of non‐tectonic hazard.

This paper provides an overview of the different types of consecutive disasters, their causes and impacts. The impacts can be distinctly different from disasters occurring in isolation (both spatially and temporally) from other disasters, noting that full isolation never occurs.

We use existing empirical disaster databases to show the global probabilistic occurrence for selected hazard types. Current state‐of‐the art risk assessment models and their outputs do not allow for a thorough representation and analysis of consecutive disasters. This is mainly due to the many challenges that are introduced by addressing and combining hazards of different nature, and accounting for their interactions and dynamics. Disaster risk management needs to be more holistic and co‐designed between researchers, policy makers, first responders, and companies.

Plain Language Summary

Many communities around the world are hit by different disasters following each other over a relatively short time. For example, in March and April of 2019, Mozambique was hit by two cyclones only weeks apart. The consequences of a sequential disaster can be, for example, that a government does not have funds anymore to address a second event if the first event was very costly. The consequences of these sequential disasters are difficult to model, and it is challenging to design good policies to address the impacts of sequential disasters. In our study, we explain how these sequential disasters occur and why it is important that we address them better in our models but also in the way we design our policies.

Key Points

• The number of countries suffering from consecutive disasters is increasing and their impacts can be distinctly different from single disasters
• An overview is provided of the state‐of‐the‐art in the understanding of consecutive disasters as discussed in the literature
• As current scientific models and policy settings do not allow to properly assess the risk of consecutive disasters and their impacts, we identify a roadmap for the future