RENO, Nev. — Geoscientists have published a large review paper in the journal Science that highlights the capacity of current models to link landscape-altering events and calls for further studies of cascading natural hazards impacting the Earth’s surface. The paper focuses on high-magnitude sediment mobilization events, such as catastrophic floods, landslides, debris flows and tsunamis, triggered by intense storm events, wildfire, earthquakes, and volcanic eruptions. In major catastrophes, there are often multiple related natural disasters taking place, and as these events move sediment downstream, they create a cascade of dominoes where one event triggers the next to come crashing down. In nature, as the dominoes fall, the events often amplify so the impacts grow larger and cover a greater area than a single event triggered in isolation.
It’s not a far reach to suggest that an earthquake along the active Mt. Rose fault could trigger landslides along the I-80 corridor, especially if that area had experienced wildfires in recent years, leading to destabilization of the soil in that area. That landslide could drop significant amounts of sediment into the Truckee River, blocking river channels. A normal rain event could then become a severe flood as the blocked channel forces the water over the riverbanks into communities. Beyond the cost of infrastructure and water resources, there are also massive ecological costs. These hypothetical events, rather than being studied individually, should be studied as a linked series of events, the researchers argue.
“No longer can we understand these events in isolation,” Scott McCoy, a coauthor on the Science paper and the Peter Vardy Endowed Professor in Engineering Geology at the University of Nevada, Reno, said. “An earthquake changes the probability of a landslide, which changes the probability of flooding.”
Scientists researching geohazards often work in silos, studying a single type of geohazard like landslides or earthquakes. A holistic approach to understanding the cascade of hazards is well worth exploring, McCoy said…