Cloud tops hint at hurricane's intensity
On September 20, 2005, Hurricane Rita rapidly intensified after entering the warm waters of the Gulf of Mexico. During that intensification, the Aqua satellite captured this image of the cloud tops of Hurricane Rita, clearly showing two hot towers in the hurricane's eyewall.
DB: This is Earth & Sky. Owen Kelley is a hurricane researcher with NASA’s Goddard Space Flight Center. He’s been using data from a satellite to study the tops of hurricanes.
JB: He’s looking at what he calls “hot towers.” They are high clouds in a hurricane’s eyewall that generate a lot of heat while condensing water vapor to form rain. He said the presence of hot towers inside a hurricane means it’s likely the hurricane will intensify.
DB: And he said that while hurricanes are now tracked by radar on the ground, the one weather radar in space can teach us how to use those ground radars more effectively.
Owen Kelley: The ground radar is really good at telling you where it’s raining now, and it even has Doppler measurements, so it can give you a sense of how fast things are moving now at the surface. But the question is: we want to know what’s going to happen next. Because when the radar first sees the hurricane, it’s just coming up along the horizon, and we want to know how bad are the winds going to be when it’s going over a city.
JB: Kelley thinks this technique will be useful to meteorologists.
Owen Kelley: As is often repeated, it’s easier to figure out where the hurricane’s going to go than it is to figure out how bad it’s going to be when it gets there. And this hot tower technique is an attempt to add one more tool in the toolbox for figuring out how bad it’ll be when it gets there.
_DB: Thanks to NASA explore, discover, understand. We’re at earthsky.org. We’re Block and Byrd for Earth & Sky.
Pictures of hot towers are available at NASA’s web site.
To learn more about the satellite used to collect rainfall data inside of hurricanes, visit the homepage of the Tropical Rainfall Measuring Mission (TRMM.)
Owen Kelley has always been intrigued by an interesting picture. He explained how this curiosity led him to hurricane research. “When I was a kid, I remember loving picture books that would have lots of details to them and just staring at them and trying to figure out the whole world that was implied by this beautiful illustrated children’s book. I mean the story, the words that were written, you shouldn’t let that distract you. It was the pictures that would inspire my imagination. And honestly, that’s kind of what happened with this hurricane thing was it was looking at hurricanes that got me thinking and I wouldn’t let go of it until I came up with something that was helping me understand hurricanes.”
Sometimes scientific instruments can give scientists information they weren’t initially looking for. Kelley said, “On the list of questions to be answered before TRMM was launched, studying hurricanes was not one of them. So this is an unintended consequence, and a pretty exciting one.”
Additional Teacher Resources
NASA: A Hot Tower Above the Eye Can Make Hurricanes Stronger
They are called hurricanes in the Atlantic, typhoons in the West Pacific, and tropical cyclones worldwide; but wherever these storms roam, the forces that determine their severity now are a little less mysterious. NASA scientists, using data from the Tropical Rainfall Measuring Mission (TRMM) satellite, have found “hot tower” clouds are associated with tropical cyclone intensification.
NASA: Hurricane Web Page
The primary hurricane page for NASA, this site provides several resources including the latest hurricane news, multimedia resources, and links to more information.
