Tampa Bay could be hit by 25-foot storm surge in Category 4 hurricane

Tampa Bay could be hit by 25-foot storm surge in Category 4 hurricane
By Chad Binette
September 16, 2005

A Category 4 hurricane could cause a storm surge of as much as 25 feet in Tampa Bay, according to a University of Central Florida researcher who is looking at the risks Florida cities face from tidal surges and flooding.

Scott Hagen, an associate professor of Civil and Environmental Engineering, and his team of graduate students have started analyzing the potential effects of a Category 4 hurricane striking the Tampa Bay region. They ran their storm surge model with wind and pressure fields for hypothetical hurricanes with three different paths and traveling at two different speeds, 5 and 15 mph. They concluded that such storms would produce surges of 20 to 25 feet in parts of Tampa Bay.

Hagen and the graduate students also plan to study the potential effects of storm surges on Florida’s east coast, particularly Miami and Jacksonville. They are conducting this early work on their own initiative with a long-term goal of helping the state become better prepared for hurricanes.

“We’ll never have a flood up to our rooftops like New Orleans, but that doesn’t mean there won’t be pockets of flooding in our cities that have the potential to cause drownings,” said Hagen, who is director of the Coastal Hydroscience Analysis, Modeling and Predictive Simulations Laboratory, which is known as the CHAMPS Lab.

Hagen said cities will have to balance their risks of storm surges with the costs of fortifying sea walls and levees when they decide how much protection they want to add. They also need to consider the gradually rising sea level, he said.

A sample map of Tampa Bay showing storm surge projections for a hypothetical Category 4 hurricane. Photo: CHAMPS Lab.

“Usually, we’ll say if we have a 99.5 percent confidence level that it’s not going to fail, we’re going to feel pretty good,” Hagen said. “We can live with that year in and year out, but there’s still that one-half percent chance, and that’s what you saw in New Orleans.”

The research team’s analysis of Tampa Bay showed the highest storm surges, about 25 feet, result from a hurricane moving at 15 mph with maximum winds of 140 mph. While the maximum storm surge levels for a storm moving at 5 mph were a few feet lower, the surge levels remained high for much longer and therefore posed more serious risks.

Graduate students working with Hagen are Peter Bacopoulos of Daytona Beach, David Coggin of Orange Park, Yuji Funakoshi of Tokyo and Mike Salisbury of Fort Pierce.

Other resources: Number of Category 4 and 5 hurricanes has nearly doubled over past 35 years: The number of Category 4 and 5 hurricanes worldwide has nearly doubled over the past 35 years, even though the total number of hurricanes has dropped since the 1990s, according to a study by researchers at the Georgia Institute of Technology and the National Center for Atmospheric Research (NCAR). The shift occurred as global sea surface temperatures have increased over the same period. The research appears in the September 16 issue of Science. Hurricane could hit Los Angeles, San Diego: San Diego has been hit by hurricanes in the past and may be affected by such storms in the future according to data from the National Oceanic and Atmospheric Administration (NOAA). While a hurricane in San Diego would likely produce significantly less damage than Hurricane Katrina in New Orleans, it could still exact a high cost to Southern California especially if the region was caught off guard. New Orleans Aquarium and Zoo to be Closed for a Year: Despite escaping Hurricane Katrina with little physical damage, the Aquarium of the Americas in New Orleans has suffered significant loss of life among its animals. Environmental problems worsened Hurricane Katrina’s impact: The loss of coastal marshlands that buffer New Orleans from flooding and storm surges may have worsened the impact of Hurricane Katrina. Hurricanes getting stronger due to global warming says study: Late last month an atmospheric scientist at Massachusetts Institute of Technology released a study in Nature that found hurricanes have grown significantly more powerful and destructive over the past three decades. Kerry Emanuel, the author of the study, warns that since hurricanes depend on warm water to form and build, global climate change might increase the effect of hurricanes still further in coming years.

In related efforts, Hagen and the students are part of a program created to improve the national system for forecasting winds, waves and storm surges related to hurricanes. The goal of that project, funded by the National Oceanographic Partnership Program, is to generate real-time, probabilistic storm surge elevations for the United States’ East Coast and Gulf of Mexico based on potential hurricane tracks. The results will help governments issue more accurate emergency advisories during storms. UCF’s partners in that effort include the universities of Miami and Florida, the U.S. Army Corps of Engineers, the National Oceanic and Atmospheric Administration/Atlantic Oceanographic and Meteorological Laboratory Hurricane Research Division and Oceanweather Inc.

Hagen and his students also collaborate with the National Weather Service Forecast Office in Peachtree City, Ga., on real-time forecasting for coastal rivers. The National Oceanic and Atmospheric Administration also is funding the CHAMPS Lab to develop a real-time forecasting system for the St. Johns River.

More information about the CHAMPS Lab is available at http://champs.cecs.ucf.edu.