Jet stream

Fast winds fly high in the sky.

These winds move from west to east. They are narrow paths of air.

These winds change our weather. They can bring rain or floods. They can even move clouds.

Planes use these winds too. The winds help planes fly faster. This helps them save fuel.

These winds are not just on Earth. We see them on Jupiter too.

They are very strong.

It is fun to learn about the sky.

High in the sky, fast winds move in narrow paths. We call these paths jet streams.

Most jet streams flow from west to east. They are found near the tropopause. This is a layer of the atmosphere.

Two main types of jets exist on Earth. The polar jet stream stays near the cold poles. The subtropical jet stream is closer to the hot equator. These winds are made by heat from the sun. They are also shaped by the Coriolis force. This force comes from the Earth spinning on its axis.

Jet streams move in wavy shapes. We call these big waves Rossby waves. These waves can split or join together. The winds are fastest where air temperatures change the most. Some winds go over 400 kilometers per hour.

These winds help us in many ways. Pilots use them to fly faster and save fuel. Weather experts study them to predict storms. Jet streams are not just on Earth. We can see them on planets like Jupiter too.

High in our sky, fast winds move in narrow paths. We call these paths jet streams.

These winds are very important for our weather. They move from west to east around the globe. Most jet streams live near the tropopause. This is a layer of the atmosphere.

They can be narrow or very long. Some jet streams might even split into two parts. They can also join back together into one stream.

Jet streams work because of heat and spinning. The sun heats the Earth in different ways. This creates large loops of moving air. The Earth also spins on its axis. This spinning creates the Coriolis force. This force pushes the moving air into new paths.

The winds are fastest where temperatures change the most. When hot air meets cold air, the wind speeds up. These winds can reach over 400 kilometers per hour. Sometimes, they even go faster than that.

People have studied these winds for a long time. An American professor named Elias Loomis first had an idea about them. He thought a strong air current moved across the United States. Later, people saw dust from the Krakatoa volcano moving around the world. They called this the equatorial smoke stream.

In the 1920s, Wasaburo Oishi found them near Mount Fuji. He used balloons to measure the wind. A pilot named Wiley Post also noticed them while flying. He saw that his ground speed changed a lot.

There are different kinds of jet streams on Earth. The polar jet stream stays near the cold poles. It usually stays between 30 and 60 degrees latitude. The subtropical jet stream is closer to the hot equator. It stays near 30 degrees latitude.

These jets can move and change shape. The northern polar jet follows the sun as it warms. It moves north when it is warm and south when it is cold. These winds can also move in waves. We call these big waves Rossby waves.

Jet streams affect many things in our daily lives. Pilots use them to fly faster and save fuel.

Weather experts use them to predict big storms. For example, a jet stream staying too far south caused flooding in Britain. In World War II, people even used them to carry balloon bombs. We can also find jet streams on other planets. They exist in the air of Jupiter and Saturn.

Jet streams are fast-flowing, narrow currents of air in the atmosphere.

These winds move from west to east around the entire globe. They are vital to our planet because they help drive weather patterns and influence climate. Most terrestrial jet streams are located near the altitude of the tropopause. The tropopause is a boundary layer in the atmosphere. Jet streams can be continuous over very long distances. However, they can also start, stop, or split into multiple parts. They might even flow in directions opposite to the rest of the stream.

These powerful winds are created by two main physical factors. First, solar radiation heats the Earth, which creates large-scale circulation cells. These include the polar, Ferrel, and Hadley cells. Second, the rotation of the planet creates the Coriolis force. This force acts on moving masses of air to change their direction. The jet stream forms at the boundaries where these circulation cells meet. For example, the polar jet forms between the polar and Ferrel cells. The subtropical jet forms between the Ferrel and Hadley cells.

There are different types of jet streams depending on their location and strength. The polar jet stream is usually found between 30 and 60 degrees latitude. It is often located near the 250 hPa pressure level. This means it sits at about one-quarter of the way up the atmosphere. The polar jet is very important for aviation and weather. In the Northern Hemisphere, the jet "follows the sun" by migrating. It moves northward as the hemisphere warms and southward as it cools. The subtropical jet is located closer to 30 degrees latitude. It is somewhat higher and weaker than the polar jet.

Jet streams do not move in straight lines. Instead, they often follow a meandering, wavy path. These large meanders are known as Rossby waves, or planetary waves. They are caused by changes in the Coriolis effect at different latitudes. Within these large Rossby waves, there are also smaller waves called shortwave troughs. These troughs move along the flow pattern around large-scale ridges and troughs. The wind speeds are highest where the temperature differences between air masses are greatest. In these areas, speeds can exceed 400 kilometers per hour. Some measurements have recorded even higher speeds.

Humans have been discovering and studying these winds for a long time. In the 1800s, American professor Elias Loomis proposed a hypothesis about powerful upper-air currents. After the 1883 eruption of the Krakatoa volcano, observers tracked a "smoke stream" of dust. This dust moved westward around the equator in a rapid current. In the 1920s, Japanese meteorologist Wasaburo Oishi detected the jet stream near Mount Fuji. He used pilot balloons, or "pibals," to measure wind speed and direction. American pilot Wiley Post also noticed the jets while flying solo around the world in 1933. He used a pressurized suit to fly at high altitudes.

Understanding jet streams has many practical uses today. Meteorologists use the location of these streams to help forecast the weather. For instance, if the polar jet stays too far south, it can cause severe flooding. In 2007 and 2012, Britain experienced major flooding due to this shift. Airlines also use jet streams to reduce flight times and save fuel. During World War II, the Japanese used the jet stream to carry Fu-Go balloon bombs across the Pacific. Scientists are even looking into whether these winds could be used for power generation.

Jet streams are not unique to Earth. Scientists have detected them in the atmospheres of several other planets. These include Venus, Jupiter, Saturn, Uranus, and Neptune.

On these gas giants, the winds play a major role in their atmospheric structure. On Earth, phenomena like the El Niño–Southern Oscillation can change where jet streams are located. This change affects the weather in the tropical Pacific and the climate of the tropics. It can even change weather in higher-latitude regions. This shows how closely the jet streams are connected to the entire global climate system.