Hurricane Hunters: How Do You Study A Hurricane From Inside Of It?

Transcript

ERIC: From the Museum of Science in Boston, this is Pulsar, a podcast where we dropsonde for answers to the best questions we've ever gotten from our visitors. I'm your host, Eric. And today we're on to part two of our series on the Hurricane Hunters. The National Oceanic and Atmospheric Administration, or NOAA, has a fleet of airplanes that fly close to and even through hurricanes in order to study their characteristics and improve forecasts. Last week, we talked with a Hurricane Hunter pilot, and today we'll find out how this fleet actually measures the properties of storms that can be hundreds of miles wide from within. My guest today is Nick Underwood, an aerospace engineer with the Hurricane Hunter fleet. Nick, thanks for joining me on pulsar.

NICK: Happy to be here.

ERIC: So let's start with what kind of data needs to be collected on these flights. Are you measuring things like wind speed and pressure?

NICK: Yeah, so I would say on our P3-Orion there are two primary data collection instruments that we use. The first are dropsondes, which are pretty much weather balloons in reverse. So instead of floating up through the atmosphere, we drop them from the bottom of the aircraft. They have sensors on board that collect atmospheric pressure, temperature, humidity, as well as the wind speed and the wind direction. Also in there is a radio transmitter, so as they're falling down through the atmosphere, they're sending that data back to the aircraft where we are looking at it and making sure that the instrument is collecting everything we need to. And then once that splashes in the ocean, we send that data off to the National Hurricane Center, and they can incorporate it into their forecast models. And then the other primary instrument that we use is called our tail Doppler radar. And so this is just like any other radar system like your local weather station would have. But this one scans up and down. And so as we're flying through the storm, we're sort of taking these slices and pictures of the storm structure. And that data has been very useful over the last few years to get a better understanding of the structure of the storms and how they're actually developing.

ERIC: So you can take these parachute probes and have them fall through and they take data the whole way down. And that way, it's almost like you're flying a bunch of planes through the storm, you're not just getting one line of data, you're actually getting a 3D idea and a picture of what the storm is doing.

NICK: Absolutely. And we will drop dropsondes all throughout the storm. And so typically, on a on an eight hour flight, we'll fly through the eye of the storm three or four times. And on each pass through, we'll be dropping sondes. As we start on our track, like midway through, we'll drop one where the winds are the highest, we'll drop one in the center of the storm, and then we'll do the same pattern on the way out. And then we'll just repeat that pattern a couple of times, and then head home for the day.

ERIC: So I assume that you're not, like, opening the back door of the airplane and chucking them out. Is there some kind of apparatus in the airplane that lets you drop them out without actually having to put the plane in jeopardy?

NICK: Yeah, so we have two chutes that come up into the cabin, one is sized perfectly for dropsondes. And there's a small door with an actuator on it that we can flip a switch at our station and it opens up that door for a second, the pressure differential between outside of the aircraft and inside of the aircraft shoots it out. And then that door closes back up. For larger instruments, such as these ocean sensing probes that we use called airborne expendable bathythermagraphs, which is a fancy way to say it's an ocean thermometer. We have a larger chute, that we can depressurize the aircraft, open that up and then drop those out as well.

ERIC: So what you're doing on a given flight is, you know, putting them in the shoots, deploying them, are you watching the data come back in real time to make sure they're working? Are you analyzing it at all? Are you just making sure it's there and then sending it?

NICK: So my job is to prepare the dropsondes, prepare the other instruments, get them out of the aircraft, watch the data as it's coming in, making sure that those instruments are working as intended. If something isn't working as intended, it's usually pretty obvious right away. And I will communicate with one of our flight directors and say, hey, this isn't working. We should launch a backup one to be sure we get the data at this point. They'll say yes, go ahead, kick out a backup. And we'll launch another one. Make sure that one works and then continue on our way.

ERIC: And you mentioned the radar in the nose looking up and down. It's the same kind of thing we use on the ground for weather forecasts here but it can give you data in real time as you're going through. You're looking at that as well.

NICK: Yeah, so we have three radar systems on the aircraft. There is the nose radar, and the pilots and meteorologists on board primarily use that for our tactics of getting through the storm. So keeping us out of the absolute nastiest parts. We've also got a multimode radar that is on the bottom of the aircraft that looks out and can see for about 300 miles. And so that gives us a good idea of where the storm is at what tracks we're going to take to get into the storm. And then the tail Doppler radar that I mentioned, that's on the back of the aircraft, that's the one that sweeping up and down. And it's sort of like an MRI. So as we're going through, we're taking an MRI of the storm.

ERIC: So can you talk a second about the technology that goes into all this and how people have been flying aircraft through hurricanes, or at least scouting hurricanes for many decades? How much better is it now than when we first started having this idea of hurricane hunting?

NICK: There's certainly been a lot of advances in the radar technology, there's a lot higher fidelity in that data. Dropsondes have improved significantly over the last couple of decades. All of those improvements to this technology, you can see that in the improvements in the forecast. I mean, what used to be 20 years ago, a three day forecast is now a five day forecast. And those extra 48 hours are critical when you're talking about potentially evacuating millions of people from stretches of coastline. And that extra time is absolutely invaluable.

ERIC: And what about the opposite? Is there any part of the technology that's either coming online better soon, or you wish was a little bit better, and you can't wait for it to improve?

NICK: We're always testing and trying to find new ways to gather more and better data on these storms. One things that we're looking at this year is launching UAS systems. So uncrewed aerial systems, drones, into hurricanes, and having those be able to fly around and collect data long after we've gone off station. And we can also use those to go places that we really can't. So operationally, when we fly through a storm, we won't go any lower than 5,000 feet. But these systems would be able to go as low as 1,000 feet or even lower. And that kind of data is critical. But like I said, it's a place that we can't go. And so this is just a new system that would allow us to go and get that. And as always, you know, we're constantly looking at new dropsonde systems and whatever else is going to help us get the best data.

ERIC: Yeah, unmanned vehicles would kind of be an awesome compliment. Because you really need the the human element, the reaction time. You know, think about exploring Mars with robots, and it takes hours just to drive to one rock because of the time delay and everything. But if you could have the unmanned drones going a lot lower going to dangerous places, while you're already there. That'd be really valuable.

NICK: It's an interesting concept. And we're excited to get even more testing with it this year.

ERIC: So I know you have experience getting these kinds of unique data on planes in places other than hurricanes. So can you give me a little bit of your background, some other things that you've done that are kind of interesting, and how you got into, you know, dropping these probes out of planes to measure different stuff?

NICK: Yeah, so I mean, me personally, I got a bachelor's degree in aerospace engineering, and started my career working for the government in flight test up in Patuxent River, Maryland, only did that for about a year before coming down here to NOAA. And we do so many missions, like outside of hurricanes, that's certainly our bread and butter and what we're most known for, but we also do atmospheric river reconnaissance, and we do marine mammal surveys, and we do climate surveys. And so I've spent several weeks up in the Arctic, flying around 500 feet above the Arctic Ocean, collecting atmospheric data, launching ocean sensing probes. I just spent a month out in Guam, doing a project where we're measuring gravity to help redefine the geode and get that dataset up to date so we can figure out exactly how high sea level is and how high everything else is. So there's tons of projects that we're always supporting. And there's always tons of engineering work that goes into it to make sure that they get off successfully. And it's really fantastic to be able to play a part in all that.

ERIC: And to wrap up, I saw that one of your passions is hurricane awareness. So for those listeners who do live near the coast, what kind of resources do you recommend?

NICK: The best resource is you can go to hurricanes.gov, which will take you to the National Hurricane Center website. There are plenty of guides and resources for how to prepare for hurricanes, what to do in the event a hurricane is headed your way. And the other bit of advice that I would give is that if a storm is heading your way to always listen to your local officials. always listen to the forecasts and warnings from the National Hurricane Center and other official outlets, and always care for your neighbors. Because even though you may be up to speed and prepared, you need to be sure that your neighbors are doing the same thing.

ERIC: Alright Nick, thanks so much for joining me and telling us all about collecting data from inside a hurricane.

NICK: Absolutely. Thank you for having me.

ERIC: Be sure to catch next week's exciting conclusion of our Hurricane Hunter series when we ask a meteorologist how the data is used to improve forecasts and hurricane science in general. To learn more about studying our dynamic planet on your next visit to the Museum of Science, check out our new planetarium show Explore: Our Changing Earth. from home. Log on to mos.org/climate to find out how climate change affects us every day. Until next time, keep asking questions.

If you liked this episode, be sure to check out:

Hurricane Hunters: Can a Plane Really Fly Through a Hurricane?

How Do Scientists Predict Tornadoes?

What Is Data?

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