Jet Streams

In addition to the winds near the surface of the earth, there are fast-moving prevailing winds that are very high up in the atmosphere. Those winds are called jet streams. As you may have guessed from the name, aircraft often take advantage of the strong currents of jet streams to move quickly across the sky. Jet streams are much faster than the winds along the ground; they can reach speeds of over 300 miles an hour. If you have ever flown from west to east across the United States, the pilot probably hitched a ride on the jet stream and hurried your journey along. Perhaps you noticed that the trip from west to east took less time than your trip back, even though you flew the same distance. The jet streams also move heat and major weather patterns around the earth.

Prevailing winds help balloonists circle the globe.

Prevailing winds circle the globe, and hot air balloonists rely on those winds to accomplish some pretty amazing feats. In 1999, Bertrand Piccard from Switzerland and Brian Jones from Britain became the first people to circumnavigate the world in a hot air balloon. The flight lasted 19 days, 21 hours and 55 minutes and the men traveled over 29,000 miles. Here is a short description of their travels.

“The team lifted off from the snowy Swiss Alps on March 1, traveled south over the North African terrain, caught the jet stream east toward the Arabian Desert, India, and over Southeast Asia. The Pacific Ocean, which has been treacherous to previous balloon attempts, was smooth, and its crossing was accomplished in six days. Catching the jet stream, they were propelled across the Atlantic on their last leg…The journey was arduous and the duo experienced winds as slow as 20 miles per hour…to speeds of 100 mph in the jet streams.” ¹

Footnotes

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