Every week WAVE 3 meteorologist Tawana Andrew breaks down what we know and what we don't about the climate and weather here in Louisville.
Bill Burton: It's time for us to take a look at the Science Behind the Forecast as I am joined by WAVE 3 meteorologist Tawana Andrew. Good morning to Tawana.
Tawana Andrew: Good morning, we're talking about something pretty relevant, especially now that we're getting further through the holidays. Travel.
BB: Yeah, Thanksgiving is coming up very fast. And there's going to be a lot of people in the air heading all over the country. So let's talk travel. What do we need to know?
TA: Well, we're specifically going to dive into how weather and changing climate can affect aircraft and air travel across the country. So of course, a lot of people have talked about how hotter temperatures can affect travel in terms of hotter temperatures, making it harder for planes to take off. And that is because air becomes less dense as the temperature goes up. And that forces an aircraft to generate more lift to take off. So that means they're going to need to either have more speed, or they're going to need more runway. And if the temperatures are high enough, there may not be enough runway available at a lot of airports for them to even get to the speed necessary for liftoff. And that can cause delays and cancellations, especially during the summer months. And once temperatures rise above 100 degrees Fahrenheit, the tarmac at various airports can actually get really soft, and cause the airplane wheels to get stuck. This actually happened back in 2012, at the Ronald Reagan airport in Washington, DC, not fun for the people on that flight.
But now that we're heading further into winter, we get to talk about the cold and those challenges, too. Because extreme cold can cause an aircrafts different metals to contract at varying rates. And that can cause weird creaking sounds, cracks, things we don't want. Cold temperatures can also cause the rubber and plastic parts of a plane to become brittle. While lubricants necessary for a plane to work are not effective anymore once the temperature really starts to drop.
And then you have snow and ice, of course, you have to put that into the equation as well. So once those start to accumulate or accrete on wings, lift is very difficult to generate. So antifreeze and deicing protocols are super important. But those can cause delays. And if the delays are long enough, they've got to start the process all over again. And that causes more delays. It's a pattern. So turbulence is another thing. That's a problem that I think a lot of people have been hearing about lately.
So wind shear is when you have a change in wind speed or direction with height, and an increase in wind shear above 15,000 feet and within the Jetstream it can lead to turbulence. And data has shown that since 1979, when shear within the upper level Jetstream over the North Atlantic has increased by 15%. That's that's a lot, especially when you think about the amount of travel that happens in that area on a daily basis. And turbulence is most often associated with storms, which pilots are trained to avoid. But clear air turbulence is also an issue. It is invisible. And it's not detectable by radar. So pilots often only know it's a problem once they're dealing with the problem.
BB: So many things to think about as we board our next flight. Gee, thanks. But at least we have a better understanding of all of it. Thanks to the latest edition of Science Behind the Forecast with WAVE 3 meteorologist Tawana Andrew. Thanks for the knowledge Tawana. Of course.
This transcript was lightly edited for clarity.