The jet stream is a narrow, meandering band of fast-flowing, high-altitude air currents in the atmosphere. Jet streams are caused by a combination of the Earth's rotation, atmospheric pressure gradients, and temperature differentials. They typically flow from west to east in a wavy pattern around the Earth, generally at altitudes of 9–16 km (30,000–52,000 feet).
There are two main jet streams in each hemisphere: the polar jet stream and the subtropical jet stream. The polar jet stream is typically found at higher latitudes, while the subtropical jet stream is located closer to the equator.
Jet streams have a significant impact on weather patterns and play a crucial role in the formation and movement of weather systems. They can influence the development and movement of storms, as well as affect the speed and direction of aircraft flying in them.
Pilots often take advantage of jet streams when flying long distances by flying in the same direction as the jet stream to reduce flight time and fuel consumption. Conversely, flying against a strong jet stream can increase travel time and fuel usage.
