• U.S.

Science: Hurricane Tracer

2 minute read
TIME

Ever since it “lost” the hurricane of 1938, which hit New England almost without warning, the Weather Bureau has sought a really dependable way of tracking hurricanes. Watching their movements from high-flying airplanes is costly, intermittent and dangerous. Radars help a lot, but what they show is belts of rain, which may be far from the center of the storm.

Last week the Weather Bureau successfully tried out an apparatus that makes the hurricane itself tell the position of its center. An Air Force B50 flew over the calm eye of Hurricane Helene, then 500 miles east of Palm Beach. A metal cylinder dropped from its bomb bay. After it had fallen a while, a plastic bag popped out and inflated to form a balloon 20 ft. in diameter. From it dangled a miniature radio transmitter.

The balloon hung steadily in the eye of the storm. Whenever it rose above a predetermined level, an automatic mechanism released a little of its buoyant gas. Whenever it sank too low, another gadget dropped a bit of ballast. Gentle breezes spiraling inward kept it always close to the storm’s calm center.

The radio signals from the first balloon were not picked up because the airplane’s receiver was not working properly, but a second balloon dropped into the same storm made itself heard. As Helene moved relentlessly toward the Carolina coast, directional radios tuned to its thin voice could locate accurately the eye’s ever-shifting position.

The Weather Bureau believes that its tracer balloons proved successful on the first try. will become an important tool for studying hurricanes. Later models will be fancier, with instruments to measure pressure, temperature and humidity in the gale-ringed eyes of the storms.

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