Dr. Daniel Gilford: Climate change and the 2024 Atlantic hurricane season
SciLine conducts interviews with experts and makes the footage available to journalists for use in their stories.
What is Experts on Camera?
Expert on Camera:
On Thursday, May 23rd, the National Oceanic and Atmospheric Administration (NOAA) announced its outlook for the 2024 Atlantic hurricane season.
On Thursday, May 23, 2024, SciLine interviewed: Dr. Daniel Gilford, a meteorologist and atmospheric scientist with Climate Central. See the footage and transcript from the interview below, or select ‘Contents’ on the left to skip to specific questions.
Journalists: video free for use in your stories
High definition (mp4, 1280x720)
Introduction
[0:00:20]
DANIEL GILFORD: Hi, my name is Dr. Daniel Gilford. I’m a climate scientist at Climate Central. I study how changes that humans bring about in the environment affect the places where they live, such as coastal communities being affected by sea level rise, hurricanes, extreme heat—the things that we are affecting in our climate, the climate of our planet are affecting the places where we live. And so, I spend a lot of my time thinking about that, communicating about that, and studying.
Interview with SciLine
In general, how do hurricane forecasters go about predicting the hurricane outlook for a season?
[0:00:53]
DANIEL GILFORD: So, when we’re looking at the ingredients that hurricanes need to form, we need some rotation. And we live on a rotating planet, so we already have that. We need some disturbances, some basic thunderstorms that are rolling off the coast of Africa or some other sort of existing thunderstorm out in the Atlantic Ocean. And then the storms, they need two other ingredients that are much more critical than the first two that are kind of just prerequisites. They need some sort of fuel to be able to strengthen. So, they need some fuel to be able to gobble up and convert that energy into wind. So, this fuel is oftentimes provided by the warm ocean temperatures that sort of underlie these storms. So, a lot of these storms that as they sort of pass over warm waters, they see that energy, they can sort of rip it up out of the ocean, convert it into wind that then they carry along with them as a sort of roll across the rest of the ocean. The other thing they need is just weaker wind shear. When we say wind shear, we really mean the difference between the wind at the top of the storm and the bottom of the storm. If the wind is sort of pushing side to side across the storm like this, all the way the same wind speed across the top to the bottom of the storm, that’s just gonna move the storm along, right. But if you can imagine a storm is almost like a spinning top, and I start to blow the wind really strongly on top and not so much on the bottom, that top will start to tip over. Now when the storm tips over because it’s facing wind shear like this, it starts to bring in environmental air, it starts to sort of rip the storm apart. So, really strong wind shear conditions lead to a reduction—and how active hurricanes can be—a reduction and how intense they can become. And so, when we’re looking at predicting what this season is going to be, those are the main things we look for: Are there are a lot of warm sea surface temperatures out there to provide the storms with potential fuel? And is there a small amount of wind shear so that there isn’t a lot of wind disrupting the growth of these storms? And in the case of the 2024 hurricane season, we have both warm sea surface temperatures and very quiet wind shear coming up.
Is there anything that stood out to you about NOAA’s forecast for the hurricane season this year?
[0:03:09]
DANIEL GILFORD: I’m not really surprised by the top line numbers. We’re seeing a very much above average season they’re predicting, and this is because of the sea surface temperatures being warmer out there. There’s a lot more fuel for these storms to be able to strengthen and grow over time. There’s also not that much wind shear as we move into a La Niña season that tends to be associated with less wind shear, which means the storms are going to be torn apart less. They have more room and space and time to grow into stronger storms. So, this is very consistent with what many of the other programs have been putting out as far as numbers—what the season could be.
How could climate change affect the frequency of hurricanes in the Atlantic this season?
[0:03:57]
DANIEL GILFORD: We know that the conditions are ripe for there to be a lot of different storms, a lot of hurricane activity—that means not only the number of storms but the intensity to which these storms can grow. The conditions are really powerful out there for a strong season. And part of that is because of human-caused climate change. We know that over the past 100 years or so we’ve been warming up the atmosphere as we emit greenhouse gases. Those gases go up into the atmosphere, they sort of trap the heat into the planet, almost like a blanket pulling—you’re pulling a blanket around yourself and trapping in the heat around your body. The same thing is happening with our planet. And as the temperature of the planet goes up, so too does the energy that we’re trapping here. And then those storms as they sort of pick up that energy and move along the ocean basin, they’re going to be becoming more powerful. And there’s more opportunity for there to be one—for one to grow spontaneously out of the warm sea surface temperatures. And so, while we don’t know the exact number of storms that we’ll ultimately have it seems to be consistent with many of the predictions, including this NOAA one, that we could have more storms. And I should note that it doesn’t really matter if there’s more storms or not, when it comes to where you are. You know, what matters is whether or not you get hit by a specific storm. It only takes one storm to really devastate a community. And so when we’re thinking about the frequency, there’s still a lot of open questions in the science about how many particular storms we may have in a given year. But we certainly know that these storms are becoming more powerful over time, as human-caused climate change warms the temperatures of the planet.
How could climate change affect the intensity of hurricanes in 2024?
[0:05:20]
DANIEL GILFORD: Hurricanes are almost like a heat engine—kind of like the engine in your car, right? And as you add fuel to the engine of the car, it starts to move forward. Well, hurricanes are a lot like that. They start to spin faster. Their rotational wind speed goes faster and faster as you add fuel to them. And just like your car, as you’re driving along, you encounter a speed limit on the road, hurricanes have a speed limit based on how warm the temperatures below them are. So, if the sea surface temperatures are quite warm, they can spin faster and faster up to a higher speed limit. And what we’re seeing right now is, in the North Atlantic Ocean, there are very warm sea surface temperatures, and there are high speed limits on what the hurricanes could be. So, if we get a storm that starts to form, it’s going to be seeing those warm sea surface temperatures, and it can grow very rapidly into a very powerful storm. And I would expect that on average, there’s going to be more powerful storms than we’ve seen in the past, just based on how warm things are out there and how quiet the wind shear is. And we expect that human caused climate change is contributing to that by increasing the amount of fuel available to these storms.
How should people prepare for this year’s hurricane season?
[0:06:58]
DANIEL GILFORD: The most important thing you can do is educate yourself about what your specific situation is where you live—what your community is doing to prepare for hurricanes. One thing you can do is go to https://www.ready.gov/hurricanes/, and you can look at the information that is provided there and sort of localize it to where you live, and what you care about. I think the other thing that we can do is have conversations. You know, hurricanes when they come along, and they affect the community, we all start to talk about the hurricanes and how we can best prepare for them, look in on your family members, your friends, your community members, make sure they are prepared and ready to sort of protect themselves from the worst of hurricanes’ influences—whether it be wind speed, or storm surge, if you live near the coast, or inland flooding, if you’re further inland from heavy rainfall. These are all potential impacts of the storms that we should be preparing our communities for. But as we’re having these conversations about hurricanes, it’s important to also think about how climate change is contributing to their changes. The atmosphere is wetter now. There’s a lot more energy in these storms, so they can become more powerful. And climate is contributing to a lot of the changes that we’re seeing in these hurricanes. So that’s an important part of the conversation, as well. And I encourage people, as you’re talking about these storms, to think about how climate is influencing them and bring that into your conversations with the people that you care about.
Is there anything you’d like to add?
[0:08:30]
DANIEL GILFORD: There are no surprises in this hurricane season outlook. We know that we have an above average season coming our way, and it’s important to stay prepared and ready for that. And it’s also important to have conversations around the climate changes that are influencing these storms that we could experience in our local communities. Talk with the people you care about: your friends, your loved ones, your local community members, the people down at the coffee shop, or your faith based community. It’s really important that we think about how climate is influencing these storms as the sea surface temperatures on the Atlantic get warmer because of human-caused climate change, as the wind shear quiets down in a La Niña season. All of these are contributing to the changes that we’re seeing in the hurricane season and we expect to see over the next few months. So, stay prepared, keep in conversation, and consider the climate implications because they really are powerful and important. And they are going to be changing the landscape for many years to come yet as well.
