What Is a Jet Stream?
A jet stream is a fast-flowing, narrow, and meandering air current found in the atmosphere of some planets, including Earth. These 'rivers of air' are located high above the surface, typically around 9 to 12 kilometers (6 to 9 miles), and flow generally from west to east.
Section 2: How Do Jet Streams Form?
Jet streams are formed by two primary factors: the heating of the Earth's atmosphere by the sun and the rotation of the Earth. They develop at the boundaries between large air masses of significantly different temperatures. This temperature contrast creates a large pressure difference, which, when combined with the Coriolis effect from Earth's spin, generates these high-speed winds.
Section 3: A Practical Example
A clear example of the jet stream's effect is in commercial aviation. An airplane flying east from Los Angeles to New York can ride the polar jet stream, gaining a tailwind that shortens the flight time and saves fuel. Conversely, the return flight heading west must fly against this current, resulting in a longer travel duration.
Section 4: Importance in Weather
Jet streams are critically important because they guide the movement of weather systems. The position of a jet stream can determine whether a region experiences cold arctic air or warm tropical air. Storms, including blizzards and thunderstorm complexes, often form along and are steered by the path of the jet stream.