How do you manage emergency responses during a stormy hurricane season? It’s still unknown what 2018 will bring storm-wise, but before a hurricane, nor’easter or tropical storm hits a coastal city the University of North Carolina at Chapel Hill’s Coastal Resilience Center of Excellence (CRC) has sent predictive analytics on storm surge, flooding, tide and wind conditions to relevant federal agencies.
Last year’s hurricane season was the deadliest on record with $306 billion in damages, of which $265 million was caused by hurricanes Harvey, Maria and Irma. Since 2008, UNC Chapel Hill has operated as part of nine university-based Centers of Excellence funded by the Department of Homeland Security. The school is currently in the third year of its second five-year, $20 million grant.
How does it all work? The CRC uses the ADvanced CIRCulation (ADCIRC) storm surge guidance system to sift data from the National Hurricane Center and the National Oceanic and Atmospheric Administration. That data is then sent to DHS and the Federal Emergency Management Agency.
Dr. Rick Luettich, the CRC’s lead principal investigator, spoke at the Department of Homeland Security Centers of Excellence Summit at George Mason University in Arlington last week, and afterward sat down with HSToday.
HST: Any idea what the 2018 hurricane season is going to look like?
Luettich: We don’t. One of the main determinants of hurricanes and the occurrence and strength of them is whether it’s going to be an El Niño year or a La Niña year. El Niño in the Atlantic tends to quash hurricanes, La Niña tends to amplify them, and we’re sort of in a transitional state, so I think it might be a very mild El Niño. That suggests it should not be quite as strong as last year, but from what I understand the forecasts are not terribly different from last year, and those are the ones that NOAA generates. The truth is that we could have a busy year and they could all stay offshore. Whether there’s a lot of them, if they’re strong and what tracks they choose to follow determines their impact.
HST: What coastal cities are at risk now?
Luettich: All of them are. I mean, up and down the U.S. coast, from the Gulf of Mexico to the Atlantic coast sea level has increased this baseline, so it’s made them all vulnerable to storm surge, and at the same time development along the coast has increased substantially. The population in coastal counties is twice the national average, so people want to live and work on the coast. It’s a very attractive area to live, but add the fact that there’s a lot of evidence that climate change is making the storms stronger, our work doesn’t suggest that, but pretty broadly in the scientific community there is good evidence of that…
A hazard isn’t a disaster by nature, only when it impacts a population. As you add all of these things together, there’s this tendency to turn hazards into disasters. So, at the Resilience Center the whole idea is to try to unwind that a little bit and better understand the risks, better communicate them and help make planning decisions so that recovery is done in such a way that these coastal cities are not as vulnerable to these storms.
HST: How do you do this?
Luettich: We work largely in predictive modeling of what the hazards are, and in the coastal zones it’s typically the response to strong storms. In the southeast and Gulf of Mexico it’s hurricanes and tropical storms and cyclones, but in the northeast it could be nor’easters as well as hurricanes like Hurricane Sandy, which made its way fairly far north. But anything on the coast that is water-related. We also do a lot of work with planning – trying to get communities to make decisions that will strengthen their ability to withstand these coastal events. We also do a lot in the recovery realm — so in the aftermath of an event, how do you get these communities back on their feet?
HST: How do you work with FEMA and DHS?
Luettich: We start out with massive databases of what the land surfaces look like, what the geometry is, what the various areas look like. Then we get data from the National Hurricane Center on the storm itself and we combine those to get a comprehensive output. For instance, the protection system around greater New Orleans that was designed by the Army Corps of Engineers used our models, so that database can be used for design applications and hazard assessments.
We had a lot of work in 2017, and in hurricanes Maria and Irma we helped the Coast Guard a lot in Puerto Rico. The Coast Guard needed to know where to position their helicopter assets. Normally they would just fly them out of harm’s way and fly the back in after the storm had passed, but in Puerto Rico that’s a large movement of assets because they have to fly over the mainland and to another island. And if they do that, it costs them money and precious time after the storm to get them back to Puerto Rico for recovery activities. We were able to give them a very accurate estimation of what the winds were going to be like in Puerto Rico so they could determine if their hangars were strong enough to withstand them. They were able to stay in Puerto Rico and assist in recovery operations after the storm.
HST: How often do you collect your data?
Luettich: So, we run our models twice a day, whether it’s at a hurricane or strong nor-easter, or any event we run our models.
HST: Have you noticed any weather patterns since the program started? What’s happening out there?
Luettich: Sure. Of course, 2005 was the year of record. You look at Katrina. We had so many storms that year that we ran out of letters in the alphabet. That remains the seminal year, and the truth is that until 2017 we had an extended quiescent period where the U.S. mainland hadn’t been hit by a major hurricane for the better part of a decade. So, depending on how you want to describe the problem, it does appear that as the climate is warming, there’s no question that sea surface temperatures are warming, there’s no question that sea level is rising — a rising sea level sets the baseline higher, so any storm that occurs is that much worse. There’s been a number of studies that have shown, like with Sandy in New York, that it was much worse in 2012 than it would have been in 1952 because of how much sea level has risen.
HST: The Coast Guard anticipate storms with your data. What about FEMA?
Luettich: FEMA uses our results largely to figure out how to position their claims adjustors immediately after a storm. FEMA position assets as well, but they jump in as soon as the storm passes by with recovery. So, oftentimes there’s not specially explicit information, like this area got six feet of storm surge, so they use our predictive models that map things spatially to give them a very accurate idea of what happened during an event. In the 2017 season, Hurricanes Harvey and Irma, and to a lesser extent Maria, they were using our model results to position their adjustors and their response people immediately after the events.
Our results tend to be highly accurate. The state of Texas also used our data considerably during Harvey to position assets. They wanted their recovery people as close to the action as possible so they could respond to emergency calls for the folks who didn’t leave.
HST: No matter what the 2018 hurricane season brings, you’re going to be busy.
Luettich: We are, and we’ll forecast any storm that looks like it’s going to have an impact on the U.S. coast.