Weather instrument found near Licking

When you grow up frequently visiting a 100-year-old Ozarks farm, you’re used to finding all kinds of “ancient” artifacts strewn about, lost and forgotten: old tools, pieces of barbed wire in the strangest locations, caches of rusted tin and unlabeled glass jugs deep in the woods.

On occasion you’ll find more recent evidence of humanity: a beer can, a Styrofoam cup, or, as brothers Glenn and Doyle Surritte in West Plains found in November, a high altitude communications transmitter. If such a find is rare, the odds of finding a similar high altitude instrument in a neighboring county days later is pretty incredible. In my case, it was a National Weather Service weather balloon.

During opening weekend in this year’s deer firearms season, a fellow hunter came up to me and described a strange looking instrument suspended from the canopy of tall pines. He thought it might be part of a weather balloon, but, knowing I am a meteorologist, he took me to the location for a closer look. Well, he was right. Printed on the side of a white box, resembling a Chinese take-out food carton, were the words “Mark IIA Microsonde(tm).” The box had a wire antenna coming from it, and it was suspended with thick white nylon string. The balloon itself was completely entangled in the canopy of the trees, along with a bright red parachute. Knowing that the National Weather Service requests these discovered instruments to be returned to them, we decided to make the effort to get it down. We had a fun time trying to reach the instrument box, which meteorologists call a “radiosonde,” about 15 feet off the ground. Eventually a combination of swatting at it like a piñata with a long stick and some rope tied around a neighboring tree allowed us to cut the box free.

The odds of finding a radiosonde are very, very small. When you consider that the average weather balloon rises above 100,000 feet in winds up to 300 miles per hour at times, these things can fly for hundreds, possibly thousands, of miles from its launch site. Given the small size of the package, it is easily lost in the woods or a large field, far from where anyone can find it. Not surprisingly, very few of the tens of thousands of radiosondes the National Weather Service launches per year are ever returned, despite a postage-paid bag to send it back to them included in the instrument box.

From experience, I know that the government’s weather forecast offices label each radiosonde with a location and launch date. Our particular package was launched from the Springfield forecast office- almost exactly 80 miles southwest from our location- at 7 p.m. on Oct. 10. There are around 60 cities that launch balloons twice each day across the United States, and only one in Missouri. Missouri is lucky to have Springfield; some states like Kentucky and Indiana don’t have balloon launch sites at all.

Even though the radiosonde uses a battery to transmit radio waves back to the launch site, the strength of the signal is not very strong- about half to a quarter of an average cell phone. The battery quickly wears out, and as such, the package is labeled on three sides with “HARMLESS WEATHER INSTRUMENT” to encourage anyone who finds one that it’s safe to handle and mail back. The battery also powers a thermometer to measure air temperature, a GPS receiver to identify altitude and airspeed, and a dew point sensor to detect humidity. Using these basic measurements, meteorologists are able to identify how much energy the atmosphere contains, wind speeds at virtually any altitude and even how likely specific types of severe or winter weather might occur. These airborne radiosondes are critically important to providing weather forecasts to save life and property.

Even though our instrument package was no longer active when we found it, there is still a record of its journey. Several Web sites on the Internet have complete records of radiosonde data, and with a few clicks of a mouse, I was able to determine that our balloon drifted northwest from Springfield, and then drifted eastward before peaking at around 108,000 feet. The balloon burst, and the instruments, slowed by a small parachute, began falling toward the surface. It had a quick jog back to the northwest just before deciding to settle onto our property. During this journey, which on average lasts 90 minutes, our radiosonde encountered winds up to 73 miles per hour (a virtual standstill in the upper atmosphere), and temperatures which plunged to minus 100 degrees. It’s pretty amazing any of these instruments survive the journey up and back down.

Unlike the Surritte brothers’ discovery, anyone who finds a National Weather Service radiosonde won’t receive an award, but returning one allows the agency to operate within budget. So, if you’re out in a field or the woods and come across what looks like a Chinese food take-out carton lying around or hanging from some trees, take pause to appreciate all the hard work that little weather instrument went through to improve your weather forecast. Just don’t forget to send it back to the National Weather Service to be launched into the atmosphere once more.

Mark Emanuel is a meteorologist from St. Louis. When he’s not working on the family farm outside of Licking, he can be heard on the new Ozarks community radio station, KZGM 88.1 FM, on Saturday nights once the station goes on the air.

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