Indianapolis, Indiana – Extreme weather events are no longer rare outliers. Storms are growing stronger, wildfires are burning larger areas, and floods are reaching places once thought safe. But scientists warn that the damage does not always end when the storm clouds clear or the flames die down. Instead, one disaster often sets the stage for another, a phenomenon researchers call “cascading hazards.”
In 2024, Hurricane Helene delivered a painful lesson in North Carolina. The storm’s record rainfall not only caused flash flooding but also destabilized mountain slopes, leading to a series of landslides that wiped out roads and homes. This chain reaction has made it harder for insurance companies and local governments to assess risk accurately. As climate change drives more intense weather, these linked hazards are becoming a critical area of study.
The urgency of new science
Indiana University Bloomington professor Brian Yanites has made it his mission to better understand these complex chains of events. A geomorphologist by training, Yanites studies how the shape of the Earth’s surface shifts over time. For him, examining a hillside or riverbank is like reading a story written into the land.
“There’s an urgency to what we’re doing as earth scientists,” Yanites said. “We’re recognizing that we really need to understand all the processes that work together to create natural hazards and disasters. These processes are changing, and rapidly. We need to do a better job of forecasting and predicting when and where these things will happen.”
Yanites is one of five principal investigators leading the Center for Land Surface Hazards (CLaSH), a new research hub supported by a $15 million award from the U.S. National Science Foundation. The center brings together experts in geology, engineering, atmospheric science, and related fields to build a clearer picture of how disasters cascade. The aim is simple but daunting: to give communities the tools they need to prepare not just for the first blow of a storm but also for the aftershocks it may unleash on the landscape.
How the land remembers
To understand cascading hazards, it helps to think about how the landscape itself reacts to disturbances. Yanites often takes his students on hikes in Indiana’s Griffy Woods Nature Preserve to demonstrate this point. Pointing to a shallow depression, he explains that it was formed decades ago when a tree blew over in a storm. The ground still bears the mark.
“The landscape remembers what happens to it,” he said.
That memory can take the form of slow changes—like a river cutting deeper into its banks—or sudden ones, such as a slope collapsing after heavy rainfall. Sediment plays a starring role in these shifts. Normally, streams carry it grain by grain, carving valleys over centuries. But during a major storm, torrents of water can move massive amounts all at once, raising streambeds and altering flow patterns.
These rapid transformations can turn a once-manageable stream into a serious flood hazard. And the effects don’t always appear immediately. After wildfires, for example, charred soil becomes unstable, leaving hillsides prone to collapse even years later.
Pressure on insurers and homeowners
The slow-burning risks of cascading hazards create major challenges for the insurance industry. A wildfire might be over in weeks, but the debris flows and landslides it triggers can remain a threat for years. Companies must decide whether to price that risk into premiums—or leave the market entirely.
“What’s happening in Southern California with insurance companies dealing with post-wildfire debris flows might be sort of the watershed moment,” Yanites said. “We have to start thinking beyond the immediate landscapes changes that come in the wake of a storm. Once we can do a better job of forecasting how those landscapes change over time and for how long, then the insurance companies will have better data to work with.”
Already, many homeowners in California are finding themselves without affordable coverage as major insurers scale back. That leaves residents more exposed and local governments scrambling to fill the gap.
Building the ‘science of scenery’
Yanites and his colleagues believe the solution lies in what he calls the “science of scenery.” Geomorphology, though still a relatively young discipline, is developing fast thanks to satellite imagery, drones, and advanced computer modeling. These tools allow scientists to track shifts in the Earth’s surface with unprecedented detail.
“Our models are still a little bit immature because we are such a young field,” Yanites said. “We want the sort of models that will eventually enable communities in places where cascading hazards happen frequently to be able to make better decisions during natural disasters.”
The CLaSH project will knit together knowledge from multiple disciplines. Atmospheric scientists can project rainfall intensity, engineers can study infrastructure vulnerability, and geomorphologists can map how slopes or riverbeds are likely to respond. By layering this information, researchers hope to generate forecasts that not only warn of the first hazard but also anticipate what comes after.
From theory to practice
For Yanites, the long-term vision is not confined to academic journals. He imagines teams of scientists working directly with communities after disasters—helping them prepare for the next hazard before it arrives. If a wildfire burns through a valley, for instance, experts could assess the risk of mudslides in the following seasons and guide local planners on where to reinforce infrastructure or relocate residents.
“That’s why we want to change the field,” Yanites said. “We want to show people the things that might happen because their landscape has changed. That is our goal and our motivation: to build general awareness and potentially help these communities that might be impacted by repeated events be better prepared.”
A growing need for awareness
Communities across the United States are already experiencing the effects of cascading hazards, from landslides in Appalachia to flooding along the Gulf Coast. Yet public awareness of these layered risks often lags behind the science. People understand hurricanes, floods, or wildfires on their own, but not always the way one disaster creates conditions for the next.
Yanites hopes that the work of CLaSH and similar initiatives will close this gap. By making the science accessible and practical, he believes communities can take proactive steps—whether through zoning decisions, infrastructure investment, or emergency planning.
Looking forward
As climate extremes intensify, the urgency of this research only grows. The stakes are not just financial but deeply human: lives lost, homes destroyed, communities fractured. Better forecasting of cascading hazards may not prevent every disaster, but it can give people a chance to act before the worst unfolds.
For Yanites, every slope, stream, and valley tells a story. The challenge now is to read those stories quickly enough to protect the people who live among them. The landscape remembers, but it also warns—and scientists are working to make sure we know how to listen.
