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Tornadoes have killed more than 530 people this year. Many scientists think some of those deaths could have been prevented, if the National Weather Service used more advanced detection and forecasting technology. NPR's Jon Hamilton reports on two efforts to improve the warnings of deadly weather.
JON HAMILTON: On May 24, a tornado touched down in central Oklahoma. KOFR TV let people know.
(Soundbite of TV broadcast)
Unidentified Man #1: There it is: tornado ground three Southwest Chickasha. Chickasha, you folks in Chickasha, you're out of time.
(Soundbite of siren)
HAMILTON: The tornado plowed through Chickasha and kept heading northeast at near-freeway speed. A storm chaser caught it on videotape.
(Soundbite of videotape)
Unidentified Man #2 (Storm Chaser): We are east of Chickasha on Highway 9, massive tornado on the ground.
HAMILTON: The National Weather Service was also tracking the twister with radar, which uses bursts of radio waves to gauge the shape, power and direction of a storm. The Weather Service radar showed this tornado would cross the southern part of Newcastle about 25 miles up Interstate 44. So officials sent emergency crews to that part of the city.
But by chance, the storm was also being tracked by a separate, experimental radar system designed to give more precise information. Brenda Philips is part of the group that's been testing the system. She says as the tornado approached Newcastle, the city's emergency manager was looking at data from their radar.
Ms. BRENDA PHILIPS (CASA): And based on that data, he could see that the tornado was actually taking a turn to the north. And so with that, he was able to redeploy these first responders who were able then to get to the impacted area more quickly.
HAMILTON: It was a big success for the group known as CASA, which was founded by several universities to improve weather radar systems.
Michael Zink is at the University of Massachusetts Amherst. Zink says that during the Oklahoma tornado, the experimental radars did a better job than traditional radars because they were able to provide a fresh image of the storm every minute.
Mr. MICHAEL ZINK (University of Massachusetts Amherst): The problem is that with the existing system you only get five-minute updates and fast-moving weather events like tornadoes can change.
HAMILTON: The existing system consists of about 150 massive radar antennas spread across the country. They sit on dedicated towers several stories high and can track storms that are more than 100 miles away. CASA wants to augment the existing system with lots of smaller radar antennas attached to buildings or cell phone towers. These new radars would provide more frequent updates. They would also offer a better view of the part of the storm that's near the ground.
Zink says you need lots of radars to do that because the radio waves they use travel in a straight line.
Mr. ZINK: And the earth is round, as we all know.
HAMILTON: As a result, the curvature of the earth blocks a radar's view of anything that's far away and low to the ground.
Zink says that means weather service radars have a big blind spot.
Mr. ZINK: So roughly 75 percent of the atmosphere below one kilometer are not covered by these radars, and that's an area where a lot of the weather is happening. And we are thinking of using our systems to fill these gaps to have better weather observations.
HAMILTON: And perhaps give people a few extra minutes' notice that a tornado is coming.
A better radar system is just one way new technology could help people protect themselves from extreme weather. Another approach involves an alternative to weather balloons. Right now, the Weather Service launches 69 of these balloons twice a day around the country. Each balloon carries sensors that send back information about temperature, humidity, barometric pressure and winds - stuff that helps forecasters predict when tornadoes are likely to appear.
Bruce Lev is part of a company called AirDat that says the 69 weather balloons just don't provide enough data for really good forecasting.
Mr. BRUCE LEV (AirDat): The solution is to essentially make aircraft, commercial aircraft, into flying balloons.
HAMILTON: Instead of dangling sensors from balloons, he says, AirDat has attached them to more than 200 planes.
Mr. LEV: If you look at the nose of an aircraft, it's one of those little tubes or blades that sort of sticks out from the front portion of the airplane.
HAMILTON: A box inside the plane collects the information and sends it to a supercomputer.
Lev says the system already gathers more than 15 times as much data as the nation's weather balloons. And he says the new technology proved itself in the days before a tornado devastated Joplin, Missouri in April.
Mr. LEV: Our forecasts were seeing severe rotation, were seeing substantial supercell activity in and around Joplin, Missouri 57 hours or more ahead of the tornadoes actually touching down.
HAMILTON: The National Weather Service buys a small amount of data from AirDat.
Scientists say there's little doubt that new technology could improve forecasting and detection of extreme weather.
But Roger Pielke, Jr. from the University of Colorado Boulder says it's not clear how many lives that would save.
Mr. ROGER PIELKE JR. (University of Colorado Boulder): If you look at where people die from tornadoes, it's often in weakly constructed homes. And it's not that they didn't know that there was a storm bearing down on them; it's that they didn't have any options.
HAMILTON: Or they did have options but made a bad decision - and no technology can prevent that.
Jon Hamilton, NPR News.
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