Nav: Home

We should use central pressure deficit, not wind speed, to predict hurricane damage

November 08, 2017

The system for categorizing hurricanes accounts only for peak wind speeds, but research published in Nature Communications explains why central pressure deficit is a better indicator of economic damage from storms in the United States.

"Sandy is the classic example. It was a very big storm, but in terms of maximum wind speed it was arguably not a hurricane," said Dan Chavas, an assistant professor of atmospheric science at Purdue University who led the study. "If you looked at the central pressure deficit, you would have expected it to cause a lot of damage. But if you used maximum wind speed, as people usually do, you wouldn't expect it to do the damage that it did."

Central pressure deficit refers to the difference in pressure between the center of the storm and outside it. Pressure and wind speed have been used interchangeably to estimate potential damage from hurricanes for years, but the relationship between them has been a long-standing riddle in tropical meteorology.

Chavas and his colleagues have defined a theory that solves that riddle. Previous work has observed that central pressure deficit depends on maximum wind speed, storm size, and latitude, but Chavas' team has determined why that is.

Scientists could use this theory to calculate peak wind speed if they had numbers for the other metrics in the equation, which could come in handy because wind speeds need to be measured at several points of a storm, making it difficult to get an accurate reading.

The research team tested their theory on two simulations of Earth.

The first used the actual distribution of sea surface temperatures and solar radiation since 1979 to produce conditions similar to real historical climate.

The second simulation produced a very simplified version of the Earth. It had no land, and ocean temperature and solar radiation were the same everywhere. This made the entire planet sort of like the tropics, meaning hurricanes could pop up anywhere - but they still tended to form at low latitudes and move westward and toward the poles, like they do on Earth.

"The idea is that if we test our theory in this very simple world, and then take it to the real world where everything is much more complicated and we get the same results, all that complexity is irrelevant," Chavas said. "People tend to work in different worlds - either the simplified world or the real world, and they don't talk to each other that much. We're bridging that gap."

The limitations of the official scale for hurricane categorization, the Saffir-Simpson Hurricane Wind Scale, have come under scrutiny recently. The wind speed meteorologists settle on is often only an estimate, and it's also highly localized because it depends on a speed sustained for a short time in one location. However, it's popular with the public and media because of its simplicity.

Some have advocated for new systems of categorization, including the Cyclone Damage Potential Index and the Integrated Kinetic Energy index. Both of these systems take into account factors other than wind speed - the idea being that more variables make a scale more valuable.

Boiling down a storm's complexity to a single number may be unrealistic, but there are surely ways to improve the current system. The Purdue team's work shows that central pressure deficit itself may achieve this goal, or at least do a better job than maximum wind speed alone.
-end-


Purdue University

Related Hurricane Articles:

Hurricane resilience in the Bahamas
A new Stanford-led study provides information on how to invest in natural coastal ecosystems that the Bahamian government, community leaders and development banks are applying in post-disaster recovery and future storm preparation in the Bahamas.
NASA finds a weaker hurricane Juliette
Hurricane Juliette has been weakening and NASA-NOAA's Suomi NPP satellite provided a look at the strength of storms within.
NASA sees Dorian become a hurricane
NASA's Terra satellite passed over the northwestern Atlantic Ocean as Dorian reached hurricane status during the afternoon of August 28, 2019.
Landslides triggered by Hurricane Maria
Hurricane Maria hit the island of Puerto Rico on 20 September 2017 and triggered more than 40,000 landslides in at least three-fourths of Puerto Rico's 78 municipalities.
NASA sees Atlantic's Leslie become a hurricane
NASA's Aqua satellite captured an infrared image of Hurricane Leslie that revealed strong storms circled the center.
NASA sees Walaka becoming a powerful Hurricane
The Global Precipitation Measurement mission or GPM core satellite passed over the Central Pacific Hurricane Center and analyzed Walaka's rainfall and cloud structure as it was strengthening into a hurricane.
NASA finds a weaker Hurricane Olivia
Infrared data from NASA's Terra satellite revealed that the area of coldest cloud topped thunderstorms has dropped from the previous day, indicating weaker uplift and less-strong storms
NASA looks at heavy rainmaker in Hurricane Lane
Cloud top temperatures provide scientists with an understanding of the power of a tropical cyclone.
Hector weakens but remains Category 4 Hurricane
Hurricane Hector has weakened slightly but still remains a robust Category Four storm at present.
UA forecast: Below-average hurricane activity
The UA hurricane forecasting model, which has proved to be extremely accurate over the years, is calling for fewer hurricanes in the Atlantic this year on the heels of a devastating 2017.
More Hurricane News and Hurricane Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.