The 16-year-old Zhai, who will be a senior this fall at La Cañada High School near JPL in southern California, and JPL research scientist Jonathan Jiang built on Zhai's science fair project, a statistical model of economic losses from hurricanes. They found that the common practice of using only wind speed to represent hurricanes in economic hurricane damage models is inadequate for large storms, such as 2012's Hurricane Sandy. Zhai and Jiang are the first to quantify the economic impacts of increasing hurricane size.
Hurricanes by the numbers
Analyzing 73 hurricanes from 1988 to the present, Zhai and Jiang found that a doubling in size, without a change in wind speed, more than quadruples the economic loss a hurricane causes. Tripling its size multiplies the loss by almost 20 times.
These numbers may be startling, but the idea that storm size matters is not. Experience has proven that not only size but the height of the storm surge, total rainfall and other characteristics affect a storm's impacts. So why do models include only wind speed? In the United States, we still classify hurricanes solely by their speed, using the Saffir-Simpson scale. The scale was devised before satellite observations made it possible to view a storm's size.
By comparison, there is no standardized scale of hurricane size. Different databases use different benchmarks -- for example, the distance from the storm's center to the location where the wind speed is either 34 or 64 nautical miles per hour, or knots. As part of their study, Zhai and Jiang recalibrated all storms to the 34-knot reference point.
From the science fair to the real world
Hurricane Sandy was the trigger for Zhai's 2013 project in the Los Angeles County Science Fair. "After seeing the devastation on TV and in the news, I was really curious," Zhai said. "I heard that it was an extremely destructive hurricane, and I noticed that it had a relatively low wind speed but an abnormally large size." Her project won third place in the Earth science division and an "outstanding achievement" award from the American Meteorological Society Los Angeles chapter.
Jiang met Zhai because he was judging other projects at the fair and stopped to see her poster. Her exceptional engagement and inquiring mind impressed him. As a long-time science fair judge, "I've met many high school students," he said. "Some people only have a high GPA because their parents put pressure on them, but Alice is genuinely interested. I put a lot of weight on people having curiosity."
Under Jiang's direction, Zhai kept working on her model to create publishable results, more than doubling the number of storms in the study and doing a more rigorous statistical analysis. The first time the authors submitted the paper, it was turned down. Some teenagers would have been crushed, but not Zhai. "Being rejected wasn't too terrible, because the reviewers' comments were encouraging," she said. "It motivated me to keep going with the project." They modified the paper and resubmitted it to the journal successfully.
Jiang encouraged Zhai to apply for an internship at the California Institute of Technology (Caltech) in Pasadena and then convinced her adviser there, Yuk Yung, to allow Zhai to expand her hurricane work at JPL this summer. She is improving their hurricane loss model by adding factors such as storm duration and regional economic wealth and using more accurate data on hurricane size based on measurements from NASA's QuikScat satellite.
Zhai is the youngest person by far in Jiang's group, but she's treated no differently than the postdoctoral fellows. "Sometimes I'm very picky, but Alice has never complained," Jiang said. In fact, she appears to be thriving. "I didn't know that my work could actually be applied to a big, real-world problem," she said. "That's kind of unbelievable. Working in a professional setting opened my mind about science. Before this experience, I wasn't sure what I was going to do, but now I want to pursue a math and science career."
The paper is available online at: http://iopscience.iop.org/1748-9326/9/6/064019/
Caltech manages JPL for NASA.
