Winds of above 300 kilometers per hour battered a two-story timber house, pulling the roof from the walls and ripping the roof from the walls. After that, there's the water. The building is engulfed by a 6-meter-high wave, which knocks the home off its base and washes it away.
Researchers developing a new state-of-the-art facility to re-create the devastation inflicted by the world's most destructive storms have a horrifying vision. Researchers were given a $12.8 million grant by the National Science Foundation in January to develop a facility that can imitate wind speeds of at least 290 km/h while also producing catastrophic, towering storm surges.
There is no facility that can create such a powerful combination of severe wind and water. But it's an idea whose time has come — and it couldn't have come at a better time.
Disaster researcher Richard Olson, head of severe events research at Florida International University in Miami, says, "It's a race against time."
Hurricanes are becoming larger, wetter, stronger, and slower as a result of human-caused climate change. The 2022 Atlantic Ocean hurricane season, which runs from June 1 to November 30, is expected to be the sixth consecutive season with more hurricanes than usual, according to scientists. Hurricanes have been quickly strengthening in recent seasons, which has been related to warming ocean waters .
According to academics, these tendencies are predicted to continue as the Earth warms even more. And coastal cities all around the world need to know how to prepare: how to create infrastructure that can withstand such strong winds and waves, such as buildings, bridges, roads, water, and electricity systems.
FIU academics are heading a team of wind and structural engineers, coastal and ocean engineers, computer modelers, and resilience specialists from all around the country to figure out how to effectively replicate these behemoths. According to Ioannis Zisis, a wind engineer at FIU, combining strong wind and water surges into one facility is unexplored ground. "It's important to push the boundaries," Zisis adds. However, "the solution" to how to accomplish it is "the answer."
Getting ready for "Category 6"
It's not as though such violent storms haven't occurred before on Earth. Hurricanes Dorian (2019) and Irma (2017) in the Atlantic Ocean, as well as super Typhoon Haiyan (2013) in the Pacific Ocean, have all recently produced storms with wind speeds above 290 km/h. Though it isn't an official title, such severe storms are commonly referred to as "category 6" hurricanes.
Hurricanes in the Atlantic and eastern Pacific oceans are rated on a scale of 1 to 5 by the National Oceanic and Atmospheric Administration, or NOAA, based on their wind speeds and potential damage. Each category is divided into 30 km/h increments.
With wind speeds of 119 to 153 km/h, Category 1 storms do "some damage," such as pulling down power lines, falling trees, and maybe ripping roof tiles or vinyl siding off a house. Catastrophic damage is caused by Category 5 hurricanes, which have gusts of up to 252 km/h and can bulldoze buildings and make areas uninhabitable for weeks or months.
But, on the official scale, a 5 is the maximum; after all, what could be more terrible than catastrophic damage? Even monster storms like Hurricane Dorian, which destroyed the Bahamas in 2019 with wind gusts of around 300 km/h, are still classified as category 5 (SN: 9/3/19).
"Strictly speaking," Olson continues, "I understand why [NOAA] does not see the necessity for a category 6." He claims, however, that there is a difference in public perception. "I view it as a new kind of storm, one that is just more terrifying."
And, labels aside, the necessity to prepare for these more powerful storms is obvious, according to Olson. "I don't believe anyone wants to be justifying why we didn't do this in 20 years," he adds. "We've put nature to the test." "Welcome to retaliation."
Simulation of a Superstorm
FIU already has the Wall of Wind, a big storm simulator situated in a vast hangar with an arc of 12 massive yellow fans anchored at one end. The fans produce a loud, disturbing hum even at moderate wind speeds — say, approximately 50 km/h. Those fans can create wind speeds of up to 252 km/h at full blast, which is equal to a low-grade category 5 hurricane.Inside the hangar, researchers build buildings that resemble skyscrapers, houses, and trees, as well as forms that simulate bumps and dips in the ground surface. Engineers from all over the world come to the site to test the wind resistance of their own designs, watching as the winds wreak havoc on their structures.
It's one of eight sites that make up the U.S. Natural Hazards Engineering Research Infrastructure, or NHERI, a nationwide network of laboratories that research the effects of wind, water, and seismic hazards.
The Wall of Wind is a wind tunnel that may be used to test complete constructions at full scale. Another wind machine, located at the University of Florida in Gainesville, can zoom in on turbulent wind behavior directly at the atmosphere-ground boundary. Then there are the massive water wave tanks at Oregon State University in Corvallis that simulate tsunamis and storm surges.
The new facility will stand on the shoulders of these titans, as well as other experimental laboratories around the country. The design phase is expected to take four years, as the team considers how to increase wind speeds — maybe with more or more powerful fans than the Wall of Wind's — and how to combine gale-force winds and enormous water tanks in a single experimental environment.
Existing labs that research wind and waves together, albeit on a much smaller size, can provide some insight into that part of the design, according to Forrest Masters, a wind engineer and the director of the University of Florida's NHERI facility.As part of the design process, a scaled-down prototype of the future lab will be built as a proof of concept. A fresh round of funding and several additional years will be required to complete the full-scale facility.
Making field observations of the aftermath of a given storm, building experimental facilities to re-create storms, and using computational simulations to visualize how those impacts might play out over large geographical regions have all been used in the past to study the impacts of strong wind storms. According to Tracy Kijewski-Correa, a catastrophe risk engineer at the University of Notre Dame in Indiana, each of these techniques has advantages and disadvantages.
"We want to put all of these techniques together in this facility," Kijewski-Correa adds, "to come as near as possible to reproducing what Mother Nature can achieve."
It's a difficult technical challenge, but one that's also intriguing. "In the larger scientific community, there's a lot of enthusiasm for this," Masters adds. "Nothing like it will exist if it is built."
