• Thu. Nov 26th, 2020

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Data collected during Hurricane Laura presents major benefits in engineering, atmospheric science fields

Data collected during Hurricane Laura presents major benefits in engineering, atmospheric science fields
Wind readings from Hurricane Laura. Credit: Texas Tech University

Hurricane Laura was the most documented hurricane to ever make landfall in the U.S.


In late August, Hurricane Laura, a Category 4 storm, made landfall in Louisiana. It was one of the strongest storms to make landfall in the U.S., as measured by maximum sustained winds.

Researchers from Texas Tech University’s Hurricane Research Team (TTUHRT), which consists of faculty and graduate students from Texas Tech’s Atmospheric Science Group and the National Wind Institute (NWI), were on the ground, tracking Hurricane Laura as it swept across the Gulf Coast.

The team deployed 48 StickNet platforms and two Ka-band Mobile Doppler Radar Trucks to take measurements and collect data from Hurricane Laura. The results? Hurricane Laura is now the most well-documented major hurricane that has made landfall in the U.S.

John Schroeder, senior director of the NWI and a professor of atmospheric science, expressed how proud he was of the TTUHRT and how perfect the deployment of their instruments was.

“We went with the limited crew due to COVID-19 restrictions, and we just absolutely nailed this event,” he said. “We were able to make a wonderful deployment that’s basically centered on the landfall point. We had 16 different monitoring systems that experienced the eyewall, the eye or some combination of the eye and the eyewall in the system. So, from a perspective of documenting the event, not only the core of it but also the extremities of it, too, we have a really good record of the wind field and the pressure field through this system. No one else has the capability to do what we do at the moment.”

Brian Hirth, a research professor at the NWI, echoed Schroeder’s sentiments.

“We did a really good, safe job of executing the plan, and we ended up collecting some of the highest wind speed and highest quality data that we’ve ever collected during a hurricane landfall,” Hirth said. “We’re excited because we know this data has the potential to really contribute, both the atmospheric science community and the wind engineering community. We’re really eager to see how we can use this data to advance our understanding of the structure of the wind in hurricanes.”

A unique storm

Schroeder noted that Hurricane Laura had several unique elements.

Data collected during Hurricane Laura presents major benefits in engineering, atmospheric science fields
StickNet platform. Credit: Texas Tech University

“Hurricane Laura was a unique storm for us in a couple of ways. We saw higher wind speeds across the fleet, in general, than we really have ever seen in our past deployments,” he said. “So, the storm was certainly a significant wind event.

“The other unique aspect of Laura was that the surge and inundation forecasts precluded us from making a deployment right by the coastal interface. The forecast was a 10- to 15-foot storm surge, and with the low-lying nature of the areas south of Lake Charles, we really used all available information to locate StickNet systems as far south as we could, but not place them in locations where they would be jeopardized. We’re always trying to ride that fine line between finding the edge of the inundation, pushing things to the coast, and yet not losing the systems. We tend to put the systems in perilous situations because that is where the science is most beneficial, but we don’t really want to lose many platforms either.”

Another unique aspect was the team also made two radar deployments in Port Arthur, one on a bridge and another on an overpass. Those instruments collected 10 hours of high-resolution data during the storm.

“That high spatiotemporal resolution enables the extraction of engineering-relevant turbulence information from the lowest levels,” Schroeder said. “We actually collect radar data focused on benefitting the engineering community first, and the atmospheric science community second, whereas most people use their radars to benefit the atmospheric science community.”

Hirth said the radar data collected was extraordinary for several reasons.

“Since the radars need to be manned during the operation, we didn’t want to be in a situation where there was a lot of wind and blowing debris that could be hazardous to the team and the trucks,” he said. “We intentionally stayed out of the very highest wind simply for safety, but we still experienced significant winds of 90 to 100 miles per hour where we deployed the radars on the west side of the storm’s circulation. We made really good decisions, both in where we deployed the StickNets and, from the radar side, where we ended up deploying. That, and the quality of data we got for the objectives, was excellent. We had about 10 consecutive hours of really high-quality radar data that will serve us for years to come.”

Stronger than Hurricane Katrina?

When reports came in stating Hurricane Laura was a stronger storm than Hurricane Katrina, a system that decimated New Orleans in August 2005, people were confused. How could Laura, a hurricane that didn’t cause nearly as much damage as Katrina, be stronger? It all comes down to the maximum sustained winds.

“Hurricane intensity is based on estimated maximum sustained wind, and sustained is sort of a misnomer,” Schroeder said. “It’s really the maximum estimated one-minute average wind speed at 10 meters that exists anywhere in that storm. It’s kind of like trying to find a needle in the haystack. It’s really hard to estimate that, especially when things are over the ocean and you don’t have a lot of measurements to work with. And then, even at landfall, if you take our measurements away and there’s just a handful, maybe less than five measurements, it’s very difficult to really identify that.

“Now, Hurricane Katrina certainly carried some damaging wind, but it carried a huge storm surge. Because of that, the intensity might have only been Category 3 at landfall, but that doesn’t mean the impact was less, because the storm surge was significantly stronger than what we had in Hurricane Laura.”

Data collected during Hurricane Laura presents major benefits in engineering, atmospheric science fields
Ka-band Mobile Doppler Radar truck. Credit: Texas Tech University

Another difference is where the storms came ashore, Schroeder said.

“If a storm comes ashore in a less-populated area, you might not hear about it quite as much,” he said. “There are a lot of rural areas where Hurricane Laura landed. If Laura came ashore at Galveston, then translated up to Houston, this event would be off the charts with respect to the damage. It’s not that there’s no damage. Don’t get me wrong, there is damage. It’s just that where it came ashore, there’s less damage than there would be if it would have come ashore in a major urban center.”

Biggest takeaway

After returning to Texas Tech to assess the data collected, Schroeder said his greatest takeaway is knowing TTUHRT can get significant information from a storm.

“When we correctly deploy this unique platform we’ve created, we can document the wind fields in a storm really well,” he said. “When you think back to how our whole hurricane program at Texas Tech has developed over the years, we made a transition from just deploying a few big towers back in 2005 to deploying a bunch of smaller ones in 2008 to present. It was Hurricane Katrina that changed our mindset. We went from a mindset of deploying a few large towers that may be taller and more ruggedized to deploying more systems that aren’t quite as rugged but could cover a lot of areas.

“As we’ve expanded over the years with the help of different funding agencies and sponsors, we’ve built that fleet up to 48 StickNet platforms. So, when we deploy and when we do it correctly, the ability to really understand what’s happened in that storm is incredible. So, I think the takeaway is just a unique ability to make really strong statements about what happened spatially underneath these tragic events.”

Hirth said Texas Tech’s longstanding history in trying to understand how wind affects structures and other elements is just one reason why others should know about TTUHRT and NWI.

“Wind research has been ongoing since the Lubbock tornado back in 1970,” he said. “That tragedy started the interest in wind hazard research at Texas Tech. With time, research interests naturally evolved from assessing damage associated with tornadoes to that associated with hurricanes. Over the years, we’ve become experienced and efficient at deploying different instrumentation into hurricanes. There’s only a handful of universities in the entire country that deploy any instrumentation into hurricanes, and Texas Tech, by far, brings the most equipment to the coast when hurricanes make landfall.”

Texas Tech being situated away from the coast doesn’t diminish the university’s research capabilities. Combining the engineering and atmospheric sciences aspects makes Texas Tech different from other institutes.

“Yes, we’re located in West Texas and we’re more separated from the coast compared to other universities in the state or in the country,” Hirth said. “But at the same time, the National Wind Institute and the TTUHRT has a unique combination of expertise where you’re combining these engineering perspectives with the atmospheric perspective. That combination is what facilitates our group’s existence and the work we do. An engineer may only care about what happens after the storm and an atmospheric scientist may only care what happens as the storm makes landfall. But bringing those two perspectives together, and developing experiments and scientific objectives that cater to that multi-disciplinary component of it distinguishes Texas Tech as one-of-a-kind.”


NASA’s orbital views of a strengthening, dangerous major Hurricane Laura


Provided by
Texas Tech University

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Data collected during Hurricane Laura presents major benefits in engineering, atmospheric science fields (2020, September 17)
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