Risk of Cascading natural disasters is on rise

Recent commentary has identified some costly and fatal disasters that exacerbate the effects of natural disasters and increase the risk of “cascade” events turning into disasters. Multi-hazard events that act like a series of falling dominoes, such as floods and landslides that occur after rain wildfires are considered cascading. These increasing risks include decision makers, city planners and risk analysts, civil engineers like us, and other stakeholders including hurricanes, wildfires, extreme precipitation, melting snow, migration and drought. The United States has recently experienced more than $1 billion in natural disasters than ever before, and climate models predict that the intensity and frequency of these events will increase in the future.

Melting snow dramatically increases the likelihood of a dry season and can make forests and vegetation more vulnerable to fire. Wildfires cloud the landscape, making it more vulnerable to landslides and flooding. For example, as reported in 2004 in Japan, severe tree damage and vegetation loss from hurricanes increases the likelihood of landslides and flooding.

Most risk studies and case studies focus on assessing the likelihood of a variety of individual extreme events, such as hurricanes, floods, and droughts. For example, two physically independent events, such as a wildfire and next season`s rainfall, are only linked by how the fire increases the likelihood of landslides and flooding. As civil engineers, we know that we need to better understand the overall severity of these catastrophes and their impact on communities and the built environment. You also need a reliable risk assessment method.

References:

AghaKouchak, A. and Vahedifard, F. (n.d.). The risk of “cascading” natural disasters is on the rise. [online] The Conversation. Available at: https://theconversation.com/the-risk-of-cascading-natural-disasters-is-on-the-rise-104192