Weather Whys; Atmospheric Data Collection

This is weather-wise. Meteorologists use a variety of weather instruments to find out about the conditions in the atmosphere. But to learn the temperature, pressure, and humidity high above the ground, they somehow need to get the instruments into the air. There are several ways of doing that. Sometimes, airplanes have instruments attached to them, so the pilot can tell scientists on the ground what conditions are at his altitude. But more often, the instruments are combined in a package called a radio-sund. That device is carried up through the atmosphere by a huge hydrogen-filled balloon. It has a small radio transmitter that tells scientists the conditions at particular points along the way. But radio-sons don't always go up from the ground with balloons. Sometimes, a sond may be attached to a small parachute and dropped out of an airplane. In that case, it's called a drop-sund. Drop-sons can be very useful for collecting weather data in remote places where there is no observing station, for instance, out at sea.

And a drop-sund flight is often much quicker than a balloon flight. The drop-sund falls at a rate of nearly a half a mile every minute, while a balloon rises more slowly. But there are drawbacks, too. A weather balloon may sometimes rise 20 or 30 miles into the sky. That means meteorologists can often get a relatively good picture of the conditions very high in the atmosphere. But a drop-sund can't measure conditions any higher than the altitude of the plane that released it. And few planes can reach the heights achieved by a weather balloon. Weather-wise is produced with the assistance of the Cooperative Institute for Mesoscale Meteorological Studies, the Oklahoma Climateological Survey, and the School of Meteorology, all at the University of Oklahoma. Our writer is Christine Harbour, our editor is Brian Wauke, and our executive producer, Karen Holbe. Weather-wise is made possible by a grant from the National Science Foundation. For Weather-wise, I'm Drew Barman.