Experts told him he was out of mind to even try it. It would never work, for so many reasons, they said. But Josh Wurman, who was then a young and reckless meteorologist just out of MIT, did it anyway. And in the process he wound up revolutionizing the way scientists study deadly tornadoes.
Back in 1995 Wurman ignored the academics, pissed off some experts and went ahead to build the first large-scale mobile doppler radar system. Mobile, because the eight-foot dish is mounted to heavy duty 27-foot trucks, weighing 25,000 pounds. Scientists can follow storms and station the mobile radar within a mile of a developing tornado, to log data more detailed and robust than any other instrument used today.
Data gathered from these mobile radar trucks form the backbone of our scientific understanding of twisters. And during this year of extraordinary storms—nearly four times the average number of tornadoes have ripped through the country, killing 515 people—this research is critical to get accurate predictions of when and where a tornado will hit, and to extend warning times beyond the current nerve-wracking 13 minutes.
Prior to 1995, and still today, scientists drop cameras, anemometers, thermometers and hygristors, strapped to tripods or heavy steel weights, into the path of a twister. But often the twister completely misses the instruments or rips them apart. “It was so primitive back then,” said Wurman. “Even getting video of a developing tornado was considered cutting-edge.”
A self-taught engineer, Wurman conjured up the idea of bringing serious radar to the actual storm. At the time he worked with the National Center for Atmospheric Research (NCAR), and the seasoned scientists and engineers were horrified by his outlandish proposal. “They’d tell me, ‘The truck will tip over when you take highway ramps, or even blow over in the extreme winds. The sensitive computer equipment will crash under the roughness of the truck,’” said Wurman. “So I left NCAR, packed up a U-Haul full of junk parts—enough to build a radar—borrowed a truck, took a faculty position at the University of Oklahoma and built this thing.” With a budget of near zero Wurman managed to get his hands on old military surplus radar parts (dishes and pedestals) that had been abandoned after the Korean war, and built the first Doppler-On-Wheels or DOW.
The DOW was deployed in 1995 during VORTEX 1, the largest field study of tornadoes at that time. (The hollywood blockbuster Twister was based on that study.) Right away they got ground-breaking data. In fact it was this day 16 years ago that they intercepted an EF4-rated tornado with 160 mph winds that nailed Dimmitt, TX, and became the most studied tornado in history at that time. Wurman’s DOWs which use an X-band, 1-inch wavelength, can detect position, intensity and relative velocity of even tiny rain droplets. Before the DOW scientists had never seen a 3D map of a developing tornado. One DOW can collect dozens of terabytes of data, while other measurement systems combined yield maybe 100 megabytes of data. “It’s the difference between what you see through a microscope versus the naked eye,” Wurman said.
Today the DOW concept has been cloned by institutions including the University of Alabama, Texas Tech University, University of Massachusetts, University of Oklahoma, as well by meteorologists in Asia and Europe. In addition to tornadoes they track hurricanes, snowstorms, wild fires, air turbulence, and more. There were 12 DOWs in use at VORTEX 2, which trumped VORTEX 1 as the largest scientific study of twisters in history. The DOW is now considered a National Science Foundation Facility, which means that they are supported by the NSF and researchers anywhere in the country can request to use a DOW for study.
We are experiencing an unprecedented year for extreme weather, but most of the DOWs are not actively chasing storms. With the $12 million in funding from the NSF and the National Oceanic and Atmospheric Association (NOAA) Wurman and his crew at the Center for Severe Weather Research are spending this season analyzing the enormous amount of data captured over the last two years during VORTEX 2, when nearly 100 scientists chased and surrounded supercell thunderstorms—the kind of storms most likely to produce a dangerous tornado. The goal of VORTEX is to understand why one supercell storm will produce a tornado and another very similar storm does not. Some of their analyses are close to being submitted to journals. Wurman says they are exploring the role of specific surges of air and the role of air temperatures in causing and intensifying tornadoes.
As for his invention that might finally bring insight into the mystery of how tornadoes form, Wurman is humble, “Innovation proceeds through a balance between reckless exuberance and conservative wisdom. You have to expect to fail. You cannot be held down by too much wisdom and yet also not waste time on frivolous ideas. I was young. Some 25-year old is probably dreaming up a generation of new ideas right now.”