Weather balloon or probe: what it is, what it is for and how it works

A weather balloon, also called a weather probe, is a tool used to study the atmosphere. Basically, it consists of a large balloon, usually made of latex or synthetic rubber, that is inflated with helium or hydrogen to make it rise to great heights.

A radiosonde is placed at the bottom of the balloon, which is a small device equipped with sensors capable of measuring different variables in the air, such as temperature, atmospheric pressure, humidity and, in many cases, wind speed and direction. All of this information is transmitted in real time to stations on the ground, allowing meteorologists to analyze how atmospheric conditions change as altitude increases.

A weather balloon is mainly used to obtain data from the atmosphere that is essential for meteorology and scientific research. Its function is to collect information in real time from different levels of the atmosphere, something that cannot be achieved only with ground stations or satellites.

Among its most important uses are:

• Improve weather forecasts: the data it transmits allows meteorologists to know the evolution of storms, cold fronts, hurricanes or even anticipate extreme phenomena such as heat waves or heavy rains.
• Study the atmosphere: By measuring pressure, temperature, humidity and wind at different altitudes, scientists can better understand how air masses behave and how they affect the climate.
• Aviation safety: information on wind currents and turbulence in different layers of the atmosphere is of great help to plan safer and more efficient flight routes.
• Scientific and environmental research: In addition to their use in meteorology, balloons are also used to study the ozone layer, air pollution and other aspects related to the environment.

The operation of a weather balloon is quite simple in appearance, but very useful in practice.

1. Inflation and launching: The balloon, made of latex or synthetic rubber, is filled with a gas lighter than air, usually helium or hydrogen. In this way it can rise and begin its journey towards the atmosphere.
2. Ascent: As the balloon rises, the air becomes less dense and the pressure decreases. For this reason, the balloon expands little by little until it reaches several meters in diameter. It can reach heights of between 20 and 35 kilometers.
3. Data measurement: hanging from the balloon travels a radiosonde, a small device with sensors that record temperature, humidity, atmospheric pressure and wind speed/direction. All this data is transmitted wirelessly to ground stations.
4. Burst and descent: when the balloon reaches a height where it can no longer expand, it ends up bursting. At that moment, the radiosonde falls towards the surface, but it does so in a controlled manner thanks to a parachute that prevents damage to the equipment and reduces risks if it falls near people or buildings.

In some cases, if someone finds the radiosonde, they can return it to be reused. Other times it is unusable after the fall.

Among the main measurements of a weather balloon we have:

• Air temperature: allows you to know how heat changes at different altitudes, which is essential for detecting cold fronts, jet streams or the formation of storms.
• Atmospheric pressure: helps identify the behavior of air masses and create more accurate weather maps. Here you can learn more about what atmospheric pressure is and how it is measured.
• Relative humidity: indicates the amount of water vapor present in the air, a crucial data for predicting rain, fog or storms.
• Wind speed and direction: obtained thanks to sensors and radar or GPS tracking. With this information, air currents, turbulence and trajectories of phenomena such as hurricanes can be studied.

Weather balloons are launched in an organized manner around the world, following strategic times and locations so that the information obtained is as useful as possible.

They are usually launched from airports, military bases, meteorological observatories or research centers, because there are the necessary personnel and equipment to receive and process the data. Thanks to this global network, a “map” of the atmosphere can be obtained at different points on the planet at the same time.

The World Meteorological Organization (WMO) establishes that launches be made twice a day, at the same time throughout the world: at 00:00 and 12:00 UTC. Thus, the information collected is comparable and synchronized, which improves the accuracy of climate prediction models.

When it explodes, the balloon disappears, but the radiosonde remains intact. To avoid a strong impact, it is equipped with a small parachute that slows its descent. Thanks to the parachute, the radiosonde descends slowly and safely, minimizing risks if it lands near people, buildings or roads.

The radiosonde can fall anywhere. Radiosondes have been found in fields, mountains, seas or even cities. Many countries include a label with instructions on the radiosonde so that if someone finds it, they can return it to the meteorological service. Sometimes they are reused, although in many cases they remain as discarded material. The important thing is that, before exploding, the balloon has already fulfilled its mission of sending valuable information about the atmosphere.

If you want to read more articles similar to Weather balloon or probe: what it is, what it is for and how it works, we recommend that you enter our Meteorological phenomena category.