Buoys await S.C. hurricane test

Offshore system might predict trouble spots before storm

By JOEY HOLLEMAN

jholleman@thestate.com

The next time a major hurricane rumbles toward South Carolina, emergency personnel will have a powerful weapon in their arsenal, a system of high-tech buoys that should help determine where aid is needed most.

The Carolinas Coastal Ocean Observing and Prediction System, or Caro-COOPS, has been arrayed off the coast since 2003, but it hasn’t been tested in major hurricane winds. The buoys’ real-time wind speed, barometric pressure and wave height readings feed into computers that crunch the numbers and come up with storm surge predictions down to the city block.

In the past, emergency personnel rushed in post-hurricane, flocking to places with known reports of damage. But people in the hardest-hit locations, such as western Mississippi after Katrina and western Louisiana after Rita in 2005, often couldn’t get out word that they needed help.

The buoy system should make it easier to locate possible trouble spots in the Carolinas even before the storm hits.

“If this system can provide reliable information for us, it will be a first time we will be able to get real-time, or near real-time, data about what a storm is doing,” said Jon Boettcher, hurricane coordinator for the S.C. Emergency Management Division. “Every time we get a National Hurricane Center forecast, as good as it is, (the information) is a couple of hours old.”

The National Oceanic and Atmospheric Administration has nearly 14,000 observing stations on land but only about 140 in coastal waters. Information gathered by planes that fly into hurricanes isn’t as timely as the buoy readings.

In recent years, the federal government has bolstered off-shore weather monitoring by paying for programs such as Caro-COOPS.

“We’re part of a community trying to create a new capacity for the country,” said Madilyn Fletcher, coordinator of the project and director of the Baruch Institute for Marine and Coastal Sciences at USC.

Local National Weather Service offices appreciate the help. Before, the Charleston office relied on information from one buoy about 40 miles off Edisto Beach and the occasional report from a pleasure craft elsewhere along the coast. Caro-COOPS added five buoys and three pier-based weather stations.

“Not only is it good to have more data out there,” said Frank Alsheimer, science officer at the Charleston National Weather Service office, “it’s good to have reliable data. (Caro-COOPS) fills a data gap.”

Even amateur weather buffs can use the information from the Caro-COOPS buoys at http://www.carocoops.org/. Surfers, especially, pay attention to offshore wave heights and frequencies to judge whether it’s worth a drive to the beach.

On a more serious note, Caro-COOPS could warn if a hurricane suddenly strengthened during its final approach to shore — or if it weakened. That information would come too late for evacuation planning, but it could help in coming up with post-storm relief strategies, Boettcher said.

“We can tell them when the flooding will recede, too,” Fletcher said.

KEEPING THEM GOING

At least she hopes they can.

The Caro-COOPS buoys have yet to be tested in a hurricane strong enough to push up a deadly storm surge. While information from the system helped prove that Gaston in 2004 should be upgraded to a Category 1 hurricane, neither Gaston nor Charley that season created much storm surge in the Carolinas.

“We hope they can withstand exposure and get information back,” Fletcher said.

The Caro-COOPS team, made up of scientists from USC, North Carolina State and UNC Wilmington, also has put together an experimental storm surge program it hopes can guide evacuation planning. Factoring in geographic information, such as the height of land above sea level and widths of waterways, the team created an array of storm surge forecasts.

For Charleston, the program gives 576 different scenarios based on different points of landfall, strengths of storms and forward velocity of the storms during their approach to land.

The worst scenario for Charleston would be the eye of a major hurricane coming ashore in the Edisto/Kiawah area. The models show which neighborhoods in Charleston likely would be flooded in that case. Everything on the Charleston peninsula east of the end of I-26 would be under water, and so would many places near tidal creeks and rivers several miles inland.

State emergency leaders incorporated Caro-COOPS’ storm surge predictions into their planning for Hurricane Ophelia last summer, but the flighty storm did a loop off the coast and never came ashore.

The buoys have held up well during the past two hurricane seasons when storms threatened the coast. But the salt water, strong winds and searing sunlight take their toll. One of the five buoys was out of order most of April. The university partners make maintenance trips offshore three times each year, at the cost of nearly $10,000 a day.

“We know how hard it is to keep them going,” Fletcher said. “But we know how important it is to keep them going.”

Reach Holleman at (803) 771-8366.