New Metric For Determining Destructive Power Of Hurricanes
April 29, 2013

Researchers Develop New Way To Measure Hurricane Season Destruction Potential

Alan McStravick for — Your Universe Online

In the last eight years alone, the US has seen seemingly low-powered storms gather strength and turn themselves into the costliest storms to ever affect our nation. This propensity for sudden storm strengthening led researchers from Florida State University to develop a new metric for the measurement of seasonal Atlantic tropical cyclone activity. This new measurement focuses not only on the size of the storm, but also on its duration and intensity. The team contends this new metric may prove valuable when factoring the potentiality for death and destruction derived from a hurricane.

The most recent example of a storm that would have benefited from this new measurement dates back to only last year. Hurricane Sandy was, according to the Saffir-Simpson scale, only a Category 2 storm. However, Sandy managed to intensify to become the largest hurricane on record, responsible for 285 deaths and becoming the second costliest storm in US history.

The researchers are calling their new measurement the Track Integrated Kinetic Energy, or TIKE. They claim their metric builds upon the previously used concept of Integrated Kinetic Energy (IKE), originally developed in 2007. IKE utilizes the kinetic energy scales along with the surface stress that causes storm surge and waves. Additionally, horizontal wind loads specified by the American Society of Civil Engineers are taken into account with IKE. The new TIKE metric is important because it takes each of the measurements of IKE and maps them over the lifespan of a tropical cyclone and over all named tropical cyclones in the hurricane season.

“Representing the activity of an Atlantic hurricane season by a number is a very difficult task,” states Vasu Misra, an associate professor of meteorology in the Department of Earth, Ocean and Atmospheric Science and FSU´s Center for Ocean-Atmospheric Prediction Studies (COAPS). “TIKE gives a succinct picture by taking into account the number of tropical cyclones in the season, the duration of each tropical cyclone and the time history of the wind force over a large area surrounding each tropical cyclone. This makes TIKE much more reliable as an objective measure of the seasonal activity of the Atlantic hurricanes than existing metrics,” Misra said.

The development of TIKE was undertaken by Misra in collaboration with Steven DiNapoli and Mark Powell. DiNapoli had worked previously as a data analyst for COAPS. Powell is currently a National Oceanic and Atmospheric Administration (NOAA) scientist stationed at COAPS. In addition to collaborating with the TIKE team, Powell was co-creator of the IKE method, upon which TIKE builds. The team published their paper, “The Track Integrated Kinetic Energy of the Atlantic Tropical Cyclones,” in the American Meteorological Society´s Monthly Weather Review.

The team has applied the TIKE metric to all hurricane seasons between 1990 and 2011. Their findings have shown an increase in TIKE values during La Niña conditions, as well as when the Atlantic sea surface temperatures were more tropical in nature. They claim this information will be instrumental in the future development of a model able to predict TIKE for an entire season. This long-term prediction ability will be an invaluable preparatory resource for emergency management organizations, as well as vulnerable businesses and citizens.

Powell commented, “I look forward to the global climate models improving enough to allow skillful predictions of storm size, which will help us predict TIKE for an upcoming season.”

The research team is careful to note TIKE is not intended as a stand-alone alternative to current available metrics but rather as a complimentary tool.

The research behind the creation of the new TIKE method was supported by grants from NOAA, the Southeast Ecological Science Center of the US Geological Survey and the US Department of Agriculture.

According to Misra, DiNapoli and Powell, it was apparent after the 2012 Hurricane Season that more and better information about the potential for destruction was necessary. Using just the IKE metric available, Hurricane Sandy, it was learned, expressed more kinetic energy than any storm between 1990 and 2006.

“That means that Sandy actually had more wind forcing over a large area than Hurricane Katrina,” Misra stated. “If the public was aware that this number was so high, which is an indication of the large potential for damage from storm surge and waves, some of them might have been able to make better life- and property-saving decisions,” he concluded.