The Truth About Weather Balloons
There has been a lot of talk about weather balloons this week, and some of the information–from a certain country to our west– has been problematic.
So let me give you the straight story on weather balloons!
Weather balloons are used by meteorologists to determine weather conditions above the surface. This is crucial because we cannot understand or forecast weather conditions without detailed knowledge of the three-dimensional structure of the atmosphere.
Two Types of Weather Balloon Systems
Some weather balloons are used to loft weather instruments that radio their observations of temperature, humidity, pressure, and wind back to the surface (see below). These devices are known as radiosondes. (see below)
Other balloons carry targets that are tracked optically from the ground. These are known as pilot balloons or pibals and can provide wind information.
Roughly 1000 radiosondes are launched twice a day around the world (see map below)
Do radiosonde and pilot balloons drift long distances around the world, as claimed by certain folks?
The answer is emphatically no.
Weather balloons expand as they rise and eventually burst, subsequently falling toward the ground. That is why all radiosondes have parachutes.
Want to see a weather balloon rise and burst? Check out this video on YouTube:
Radiosondes typically ascend to around 100,000 -110,000 ft before bursting, quite a bit higher than the recent Chinese “weather balloon”, which was drifting at 60,000 ft.
And weather balloons don’t get far before they fall to earth–no more than 100 miles or so, even with the strongest winds aloft.
There are some companies that are trying to develop long-range balloons that can be used to collect weather data, act as communications hubs, or be applied for other purposes.
For example, a company called Windborne Systems has a long-range balloon that can move up and down from the surface into the stratosphere, taking observations or other tasks.
And Google tried its hand at a long-range balloon that could provide internet to remote locations: their LOON program. Unfortunately, that project was cancelled in 2021.
Finally, balloons have a long history of use for military surveillance operations, but that is a story for another blog.