Name in the News: Alison Nugent

It’s not such a shock that Alison Nugent, 31, would end up in meteorology, or “atmospheric science,” in University of Hawaii academic terms. She was in touch with nature through her childhood in Massachusetts — relishing those long treks through the woods. And she went on to earn undergraduate through doctoral degrees at Harvard and Yale universities.

But she’s been rather more a private person outside the classroom. Since taking an assistant professor post in January 2017, she generally spends time with her husband at home nearby in Manoa, or island-hopping every chance they get on long weekends, getting to know the state.

Suddenly, however, something called Hurricane Lane drew her before the KHON TV camera. It’s Hurricanes Norman and Olivia on the public viewscreen now, but a few weeks back, Nugent was one of the expert sources watched by nervous Hawaii residents who, clinging to their TV sets, tracked the approach of the storm over a full weekend.

“The three primary threats from a tropical storm are storm surge, rain and wind,” she said. “To scope out the threat, you need to know the strength and size of the storm and the storm track. Numerical models can provide this guidance to varying degrees of success.

“If the ‘cone of uncertainty’ illustrating the most likely storm track intersects the shoreline, the threat to life and property increases drastically.”

Nugent was tapped for her observations by weather anchor Justin Cruz in an extended appearance on the station’s Hurricane Lane coverage. Earlier that week, she had raised her concern with family and friends on the mainland, but by the time Hawaii folks plugged in, she was feeling a bit better about it.

Nugent sees some of the TV outreach as part of her job as an educator. Now people recognize her face in public — though, she noted, it’s all good being associated with a storm that, strictly speaking, didn’t hit full-force.

“I was having a blast — I love talking about atmospheric science,” she said. “And I forgot I was on live TV … I think the most surprising thing was how much people enjoyed learning.

“This entire experience has been incredibly heartwarming for me. Thank you, Hawaii!”

Question: Could you explain to us non-scientists how you initially “size up” the threat a tropical storm poses? What are a few of the factors you check?

Answer: To “size up” the threat of a tropical storm, meteorologists first view model guidance. Weather models are effectively a complex set of mathematical equations that estimate atmospheric processes. However, models will differ in the realization of the storm progression, track and strength.

Hurricanes are extremely nonlinear so a tiny difference in one model value can have a butterfly effect when propagated forward in time.

For this reason, forecasters study the storm environment, in observations and in the models, to look for patterns they may have seen before, or some hint at which model is the most accurate based on their extensive prior knowledge.

In the case of Hurricane Lane, forecasters knew that once the storm encountered wind shear and weakened, it would turn westward; it was just a matter of when it would weaken and how quickly, which affected the forecast track.

Q: There was severe flooding damage, of course, but at what point did you feel fairly certain that Lane would not deliver a direct hit, full force?

A: I felt fairly certain that Lane would not deliver a full-force direct hit to any of the Hawaiian islands when it began to weaken on Thursday and Friday. Thursday it weakened to a category 3, and when I woke up Friday morning it had weakened to a category 2.

The reason the weakening is so important is due to the steering levels of a hurricane. A stronger storm is directed by upper-level winds while a weaker storm feels more influence from lower-level winds.

Therefore, the faster Hurricane Lane weakened, the sooner it would feel the low-level trade winds coming from the east, and the sooner it would turn westward, avoiding a direct impact to the islands.

Q: Can you cite a couple of factors that tend to “protect” Hawaii from more frequent hurricane threats?

A: Hawaii is relatively safe from hurricane threats due to two primary environmental factors. The first is wind shear, found climatologically over the state. At low levels we experience trade winds from the east but at upper levels, typically winds from the west are found. Symmetry is very important for hurricane strength, so a difference in the background wind destabilizes a storm and causes it to weaken.

The second factor is the sea surface temperature. Hurricanes are driven by latent heat release as water vapor condenses to liquid water, so the more water vapor that is available, the more energy available to fuel a storm.

High values of water vapor are found over warm oceans, ideally warmer than 83 degrees Fahrenheit. Most of the time our sea surface temperatures don’t get that high around Hawaii. As storms approach cooler sea surface temperatures, they have less fuel to keep them going and therefore weaken.

Finally, in some cases the Big Island provides protection. The large mountains of Mauna Kea and Mauna Loa can disturb the low-level wind fields and weaken a storm as a last resort. This was likely a factor with Hurricane Lane, especially because it was slow-moving.

However, this does not mean that Hawaii cannot experience a strong hurricane. A fast-moving storm, or one with a more westward storm track can still reach us, even with the Big Island’s protection.

Q: What drew you to the study of atmospheric sciences generally, and to the Pacific region in particular?

A: I love that atmospheric science is something that you can see with your own eyes. You don’t need a microscope or any other scientific tools. When you learn about cloud formation and convection, you can look up and see it in action.

Many people get into atmospheric sciences after a severe weather event sparks their interest, but that isn’t my story. I’ve always loved science and math, and was drawn to Earth Sciences because I could see it in action every day.

Q: What are the tracks for study in your field? Do you have guidance for your students considering a career?

A: To become an atmospheric scientist, typically a student will major in a STEM (science, technology, engineering, math) field in their undergraduate degree. It could be math, applied math, physics, or in the case of University of Hawaii at Manoa, it could be Atmospheric Sciences from the get-go.

For careers at the National Weather Service, only an undergraduate degree is necessary, but the degree must include a minimum number of semester hours of atmospheric dynamics, thermodynamics, synoptic (large scale) and mesoscale (medium scale) meteorology, physical meteorology, instrumentation, physics and ordinary differential equations.

For careers that involve research, typically a master’s degree or a Ph.D. degree in a specialized atmospheric or Earth Science field is necessary. If you think you may want to do research, you can always get involved in a research project to get some experience. Don’t be shy, just ask!

In general, math and physics are the backbone of atmospheric sciences, so start early to strengthen your math and physics skills. In today’s world with our reliance on computers for modeling and visualizing, computer science is also becoming a necessity.

Q: How do you approach storm preparation for your own home?

A: To prepare for Hurricane Lane, I purchased gallon jugs of water and non-perishable food. I also filled up the bath tub in my home with water, along with some buckets, large bowls and pitchers. I brought my potted plants inside along with anything else that could be blown around.

I pulled out all of my flashlights, candles and external charger. I also had tape on hand in case I needed to tape shut my jalousie windows. In the future, I’ll store all of these things together so it’s easy to find for next time!