Meteorologists from Penn State College, Pennsylvania, have taken inspiration from the movie Twister to develop a way to capture thermodynamic data within and around a tornado. The data obtained will help explain how tornadoes are formed.
In the 1990s action movie Twister, probes are launched into a storm by driving a cruise-controlled truck filled with sensors into a tornado. Penn State researchers, seeking to fill a void in thermodynamic data, have developed a similar idea that uses helium balloons and a low-cost delivery system for commercially available probes.
The 13g probe uses two balloons to achieve altitude before one balloon is remotely jettisoned, allowing the probe, carried by the remaining balloon, to drift with the winds. Each device is capable of measuring temperature, humidity, pressure and GPS location in real time. Researchers are able to track as many as 34 probes, although that number increases to hundreds in the newest probe prototype.
“In Twister, probes were levitated by a tornado,” said Paul Markowski, professor of meteorology at Penn State College of Earth and Mineral Sciences. “We just float the probes above the ground and the storm’s internal wind field draws them in. If you have the right kind of storm and launch from a sensible area, it’s hard to miss.”
The system was successfully used in May this year with supercell storms, the most likely precursor storms to tornadoes, near Mannsville, Oklahoma, and Gove City, Kansas. Researchers launched 20 probes, which drifted through each of the storms for about 90 minutes, collecting data that had previously only been estimated using computer modelling.
Meteorologists use radar to build up a broad view of the windfield of a storm, but know little about how forces associated with temperature and pressure can change that wind. This research aims to explain why the winds evolve and what causes tornadoes to form. The next step in the research is to link the new temperature data with existing radar wind data to begin searching for patterns. Knowing this relationship could help forecasters better predict if a supercell storm will turn into a tornado.
Yvette Richardson, professor of meteorology at Penn State College of Earth and Mineral Sciences, said, “The radars give us what the winds are doing and these probes tell us what the temperature pattern looks like in relation to the wind. Knowing the thermodynamics within a storm helps us evaluate our theories for how tornadoes form. Right now, they’re all based on our assumptions of what those look like from either numerical models or from observations we have from cars that drive around underneath a storm. We know how temperature varies along the ground but not above that. This research adds that missing link.”
The researchers are working with a company that is developing a prototype that is much lighter, which will cut down on the size of the balloons, reducing filling times and increasing the likelihood they’ll be sucked in by a storm. Other options, such as balloons that can be inflated in advance, are also being pursued.
- October 2017