In the other hand, the scientist grasps a radiosonde, a lightweight cardboard box filled with scientific instruments that's tied to the bottom of the balloon. As the balloon hurtles away from the Earth, the radiosonde is already hard at work, beaming atmospheric information back to data centers.
It may have started out modestly, but now, at almost 18 miles (29 kilometers) high, the balloon has swelled to the size of a moving truck. Stretched to its limit, the balloon's thin synthetic rubber bursts and sends the tiny radiosonde plummeting back toward Earth.
Within seconds, the wind catches a small, orange parachute and slows the device's descent. Hours later -- and hundreds of miles from where it first lifted off -- the weather balloon touches the ground.
More than 70 years after scientists sent up the first experimental weather balloon, they remain the workhorses of modern meteorological forecasts. Whether it's a tornado warning or the weather report on the 6 o'clock news, weather balloons are what keep people on the ground tuned in to the meteorological workings of the upper atmosphere.
Tagging along for the ride was John Jeffries, an American physician known for dabbling in weather observation. In the skies above Northern Europe, Jeffries hoped to record some first-ever measurements of the upper atmosphere.
When the balloon came dangerously close to crashing into the English Channel, however, Jeffries was forced to toss his equipment overboard to lighten the load. It may be sunny and quiet at sea level, but at 18,000 feet (5,486 meters), a weak storm system could soon turn into something more dangerous.
By sending up regular squadrons of balloons to measure the conditions of the upper atmosphere, meteorologists can keep tabs on brewing storms. With such a limited data set, the best meteorologists can do is predict the weather a few hours into the future.
High-altitude weather data is critical for predicting oncoming natural disasters like tornadoes, thunderstorms or flash floods. Thanks to weather balloons, officials can scramble supplies and emergency personnel to an affected area hours before a weather disaster strikes.
In 2009, Massachusetts Institute of Technology scientists Oliver Yes and Justin Lee used a weather balloon, a cooler, a cell phone and a digital camera to take a high altitude photograph of the Earth for less than $150. Of course, Yes and Lee warn that launching things into the stratosphere can be dangerous .
If it's not equipped with proper parachutes, an amateur weather balloon can become a deadly projectile if it falls in an urban area. The balloons could also provoke a disaster by getting sucked into the jet engines of a passing airliner.
During a meteor shower, a high-altitude balloon can collect cosmic dust emitted by the passing space rocks. Occasionally, an American homeowner wakes up to find a spent weather balloon in his or her backyard.
The slide is coated with film of lithium chloride (ICL), the electrical resistance of which changes based on the surrounding humidity. As the air pressure around it decreases at higher altitudes, the canister expands, triggering a sensor.
The radiosonde also has a low-powered radio transmitter to relay data from all three instruments back to receivers on the ground. The advantage of a radiosonde is that scientists don't need to retrieve the device to obtain weather data.
Holding the whole assembly aloft is a large balloon made of neoprene, a synthetic rubber. The balloons are filled either with helium or hydrogen depending on the preferences of the individual launch station.
However, hydrogen is also very flammable -- a fact that has prompted many explosion-shy weather stations to adopt helium instead. Altogether, a complete weather balloon assembly costs about a few hundred dollars.
In an isolated field in the middle of Australia, NASA officials slowly inflated a massive helium balloon that would carry a $2 million gamma ray telescope into the upper atmosphere. Crew members ran for their lives as the telescope smashed into a nearby SUV and ripped through a fence before crumpling into a heap more than 492 feet (150 meters) away.
Of the many things that can go wrong during a balloon launch, leaving a trail of destruction is obviously one of the worst. In the United States, weather stations will typically have an onsite shed built especially for the purpose of balloon inflation.
As it fills, he tests the radiosonde's battery, tunes the radio equipment and attaches the whole assembly together with a length of nylon cord. Once the balloon has inflated to about the size of a yoga ball, the technician ties it off and ushers it outside.
Walking the balloon a short distance clear of trees, power lines and other obstacles, he'll simply give it a gentle push upward. As soon as the balloon begins to float, the radiosonde gets to work, beaming data to weather computers on the ground.
By noting the sideways movement of the ascending balloon, they can calculate wind speed and direction at different altitudes. With less air pressure to rein it in, the gas inside the balloon expands as its altitude rises.
The balloon can only expand so much, however, and it will typically burst at altitudes above 15 miles (24.1 kilometers) -- about three times higher than Mount Everest. If the radiosonde was simply allowed to plummet to earth, it could wreak deadly havoc on human settlements below.
As the balloon ascends, the parachute remains folded by the downward rush of air. When the assembly starts to descend, however, the parachute is blown open, slowing the balloon to a manageable 22 miles per hour (9.8 meters per second).
If balloons catch a particularly strong gust of wind, they can travel several hundred miles -- touching down anywhere from a marshy bog to the snowy peaks of the Rocky Mountains. Sending helicopters to pick up almost 200 weather balloons launched in the United States each day simply isn't in the budget.
It consists of a radiosonde attached to a balloon that measures temperature, humidity, air pressure, wind, and other data, which are sent back to a base station on Earth for analysis. Although thousands of these “mobile weather stations” are launched every month across the world, not that much is known about exactly what they are and how they work.
During the introduction, this article already provided a concise and cryptic of what a weather balloon is. One need a more elaborate explanation though, before exploring its characteristics and operation in more detail.
This data is transmitted back to earth via a device called a radiosonde, which is used by meteorologists to analyze current and forecast future weather conditions. It can be anything from 6 to 8 feet (1.40 to 2.40 meters) in diameter, depending on the weight of the instrumentation and the height the balloon needs to reach.
The shape and size of a weather balloon largely depend on its altitude. But meteorologists know it will rapidly expand as it gains altitude and doesn't want it to burst too early in its ascent.
At the bottom, an array of weather instruments called a radiosonde is connected to the balloon. The latex material is normally filled with either hydrogen or helium to lift the balloon to the desired height required by the meteorologists.
Weather balloons are capable of reaching heights of 100 000 feet (30 480 meters) within an hour after being launched from the surface. The weather balloon's (radiosonde) payload starts falling to the ground, but a small orange parachute attached between the radiosonde and balloon gently guides it down back to Earth.
Yet, you have to take into consideration the fact that the onboard instruments start sending back precious data from the moment the balloon is launched all the way until it reaches a height of 100 000 feet an hour later. Even more so, you will now realize what an important role weather balloons play in the meteorological field and how vital they are to gather very important data needed by meteorologists to understand current weather conditions and forecast future weather events.
Before the days of radar and satellites, weather balloons offered a tantalizing glimpse into conditions high above the Earth's surface. While weather balloons may seem out-of-date by modern standards, agencies across the globe still rely on balloons to help predict the weather.
These relatively simple devices carry gauges to capture information about wind, temperature and humidity levels, which meteorologists then use to draft your daily forecast. In 1936, scientists added radio transmitters to weather balloons to transmit data to the ground, eliminating concerns over how far the balloons would travel.
The entire time it rises, it sends information back to the ground, often as many as 1,000 to 1,500 readings per balloon on everything from temperature to wind direction. As it ascends into the sky, the decreasing air pressure causes the balloon to swell to up to 6 meters (20 feet) in diameter.
Though each unit comes with instructions on how to mail it back to the National Weather Service, along with a readdressed, postage-paid package, only about 20 percent are ever returned.