
A weather balloon, also known as a sounding balloon, is a
balloon
A balloon is a flexible membrane bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air. For special purposes, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), ...
(specifically a type of
high-altitude balloon) that carries instruments to the stratosphere to send back information on
atmospheric pressure
Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1,013. ...
,
temperature
Temperature is a physical quantity that quantitatively expresses the attribute of hotness or coldness. Temperature is measurement, measured with a thermometer. It reflects the average kinetic energy of the vibrating and colliding atoms making ...
,
humidity
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation (meteorology), precipitation, dew, or fog t ...
and
wind speed
In meteorology, wind speed, or wind flow speed, is a fundamental atmospheric quantity caused by air moving from high to low pressure, usually due to changes in temperature. Wind speed is now commonly measured with an anemometer.
Wind spe ...
by means of a small, expendable measuring device called a
radiosonde
A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculat ...
. To obtain
wind
Wind is the natural movement of atmosphere of Earth, air or other gases relative to a planetary surface, planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heatin ...
data, they can be tracked by
radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...
, radio
direction finding
Direction finding (DF), radio direction finding (RDF), or radiogoniometry is the use of radio waves to determine the direction to a radio source. The source may be a cooperating radio transmitter or may be an inadvertent source, a naturall ...
, or navigation systems (such as the satellite-based
Global Positioning System
The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide ge ...
, GPS). Balloons meant to stay at a constant altitude for long periods of time are known as ''transosondes''. Weather balloons that do not carry an instrument pack are used to determine upper-level winds and the height of cloud layers. For such balloons, a
theodolite
A theodolite () is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes. The traditional use has been for land surveying, but it is also used extensively for building and ...
or
total station
A total station or total station theodolite is an electronic/optical instrument used for surveying and building construction. It is an electronic transit theodolite integrated with electronic distance measurement (EDM) to measure both vertic ...
is used to track the balloon's
azimuth
An azimuth (; from ) is the horizontal angle from a cardinal direction, most commonly north, in a local or observer-centric spherical coordinate system.
Mathematically, the relative position vector from an observer ( origin) to a point ...
and elevation, which are then converted to estimated wind speed and direction and/or cloud height, as applicable.
Weather balloons are launched around the world for observations used to diagnose current conditions as well as by human forecasters and
computer models
Computer simulation is the running of a mathematical model on a computer, the model being designed to represent the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determin ...
for
weather forecasting
Weather forecasting or weather prediction is the application of science and technology forecasting, to predict the conditions of the Earth's atmosphere, atmosphere for a given location and time. People have attempted to predict the weather info ...
. Between 900 and 1,300 locations around the globe do routine releases, two or four times daily.
History
One of the first people to use weather balloons was the French meteorologist
Léon Teisserenc de Bort. Starting in 1896 he launched hundreds of weather balloons from his observatory in
Trappes
Trappes () is a Communes of France, commune in the Yvelines departments of France, department, Île-de-France Regions of France, region, Northern France. It is a banlieue located in the western outer suburbs of Paris, from the Kilometre zero, c ...
, France. These experiments led to his discovery of the
tropopause
The tropopause is the atmospheric boundary that demarcates the lowest two layers of the atmosphere of Earth – the troposphere and stratosphere – which occurs approximately above the equatorial regions, and approximately above the polar regi ...
and
stratosphere
The stratosphere () is the second-lowest layer of the atmosphere of Earth, located above the troposphere and below the mesosphere. The stratosphere is composed of stratified temperature zones, with the warmer layers of air located higher ...
.
Transosondes, weather balloons with instrumentation meant to stay at a constant altitude for long periods of time to help diagnose radioactive debris from atomic fallout, were experimented with in 1958.
The
drone technology boom has led to the development of
weather drones since the late 1990s.
These may begin to replace balloons as a more specific means for carrying radiosondes.
Materials and equipment
The balloon itself produces the
lift, and is usually made of a highly flexible
latex
Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature, but synthetic latices are common as well.
In nature, latex is found as a wikt:milky, milky fluid, which is present in 10% of all floweri ...
material, though
chloroprene may also be used. The unit that performs the actual measurements and
radio transmissions hangs at the lower end of the string, and is called a
radiosonde
A radiosonde is a battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculat ...
. Specialized radiosondes are used for measuring particular parameters, such as determining the
ozone
Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , break ...
concentration.
The balloon is usually filled with
hydrogen
Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...
, though
helium
Helium (from ) is a chemical element; it has chemical symbol, symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert gas, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is ...
– a more expensive, but viable option nonetheless – is also frequently used. The ascent rate can be controlled by the amount of gas with which the balloon is filled, usually at around .
Weather balloons may reach altitudes of or more, limited by diminishing pressures causing the balloon to expand to such a degree (typically by a 100:1 factor) that it disintegrates. In this instance the instrument package is usually lost, although a parachute may be employed to help in allowing retrieval of the instrument. Above that altitude
sounding rocket
A sounding rocket or rocketsonde, sometimes called a research rocket or a suborbital rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The rockets are often ...
s are used to carry instruments aloft, and for even higher altitudes satellites are used.
Launch time, location, and uses
Weather balloons are launched around the world for observations used to diagnose current conditions as well as by human forecasters and
computer models
Computer simulation is the running of a mathematical model on a computer, the model being designed to represent the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determin ...
for
weather forecasting
Weather forecasting or weather prediction is the application of science and technology forecasting, to predict the conditions of the Earth's atmosphere, atmosphere for a given location and time. People have attempted to predict the weather info ...
. Between 900 and 1,300 locations around the globe do routine releases, two or four times daily, usually at 0000
UTC and 1200 UTC.
[ Some facilities will also do occasional supplementary special releases when meteorologists determine there is a need for additional data between the 12-hour routine launches in which time much can change in the atmosphere. Military and civilian government meteorological agencies such as the ]National Weather Service
The National Weather Service (NWS) is an Government agency, agency of the Federal government of the United States, United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weathe ...
in the US typically launch balloons, and by international agreements, almost all the data are shared with all nations.
Specialized uses also exist, such as for aviation interests, pollution monitoring, photography or videography, and research. Examples include pilot balloon
A ceiling balloon also called a pilot balloon or pibal, is used by meteorologists to determine the height of the base of clouds above ground level during daylight hours. In the past, and sometimes today, a theodolite was used to track the ba ...
s (Pibal). Field research programs often use mobile launchers from land vehicles as well as ships and aircraft (usually dropsonde
A dropsonde is an expendable weather reconnaissance device created by the National Center for Atmospheric Research (NCAR), designed to be dropped from an aircraft at altitude over water to measure (and therefore track) storm conditions as the dev ...
s in this case). In recent years, weather balloons have also been used for scattering human ashes at high altitudes.
The weather balloon was also used to create the fictional entity 'Rover' during the production of the 1960s TV series ''The Prisoner
''The Prisoner'' is a British television series created by Patrick McGoohan. McGoohan portrays Number Six (The Prisoner), Number Six, an unnamed British intelligence agent who is abducted and imprisoned in a The Village (The Prisoner), mysteri ...
'' in Portmeirion, Gwynedd, North Wales, UK in September 1966. This was retained in further scenes shot at MGM Borehamwood UK during 1966–67.
Environmental issues
While weather forecasting is increasingly reliant on satellites and radar technology, it still heavily involves the use of weather balloons. These devices, launched from thousands of stations worldwide, ascend into the atmosphere to collect meteorological data. The United States, for example, releases approximately 76,600 balloons annually, while Canada launches 22,000.
Weather balloons, after reaching an altitude of approximately 35 kilometers, burst, releasing their instruments and the latex material they are made of. While the instruments are often recovered, the latex remains in the environment, posing a significant threat to marine ecosystems. Studies have shown that a substantial portion of weather balloons eventually end up in the ocean. For instance, one Australian researcher collected over 2,460 weather balloon debris from the Great Barrier Reef
The Great Barrier Reef is the world's largest coral reef system, composed of over 2,900 individual reefs and 900 islands stretching for over over an area of approximately . The reef is located in the Coral Sea, off the coast of Queensland, ...
, estimating that up to 300 balloons per week may be released into the marine environment. This environmental impact underscores the need for sustainable alternatives in weather data collection.
Scientists and environmentalists have raised concerns about weather balloons' environmental impact. The latex material, which can persist in the ocean for extended periods, can harm marine life, including sea turtles, birds, and fish. Efforts to minimize the environmental impact of weather balloons include developing biodegradable materials and improved recovery methods. However, the continued reliance on weather balloons for meteorological data challenges balancing the need for accurate weather forecasts with environmental sustainability.
See also
* Atmospheric sounding
* Ceiling balloon
* High-altitude balloon
* SCR-658 radar
* Skyhook balloon
* Timeline of hydrogen technologies
This is a timeline of the history of hydrogen technology.
Timeline
16th century
* c. 1520 – First recorded observation of hydrogen by Paracelsus through dissolution of metals (iron, zinc, and tin) in sulfuric acid.
17th century
* 1625 – F ...
* High-altitude platform
References
External links
Atmospheric Soundings for Canada and the United States
– University of Wyoming
– University of Hawaii
– NSSL
* ttps://web.archive.org/web/20070704045456/http://www.ua.nws.noaa.gov/photo.htm Kites and Balloons– NOAA Photo Library
NASA Balloon Program Office
– Wallops Flight Facility, Virginia
National Science Digital Library: Weather Balloons
– Lesson plan for middle school
Pilot Balloon Observation Theodolites
– Martin Brenner, CSULB
– Historical recompilation project on the use of stratospheric balloons in the scientific research, the military field and the aerospace activity
{{Earth-based meteorological observation
Earth observation balloons
Atmospheric sounding
Meteorological instrumentation and equipment
Scientific observation
French inventions