You might hear pilots talking about headwinds and tailwinds, but how does the jet stream actually affect your flight? More to the point: What is the jet stream?
The jet set
You’ve seen that big band on the weather maps, and you know that it occasionally drags that cold, crisp air down from the north and makes you mutter under your breath about how the Canadians should keep their air.
But maybe you’ve noticed when you’re flying across the country — or the ocean — that your flight times out and back are different. So what’s the deal?
The air up there
While the existence of the jet stream — or at least the effects thereof — were first observed following the eruption of Krakatoa in 1883, it was Japan’s Wasaburo Ooishi who launched pilot balloons from a site near Mt Fuji and tracked their progress in the 1920s, establishing the nature of the powerful upper level current.
His work went largely unnoticed outside of Japan, however, and the German meteorologist Heinrich Seilkopf is credited with creating the term Strahlströmung — literally, “jet streaming” — in 1939, which we’re familiar with today.
What it boils down to is, between altitudes of 23,000 and 39,000 feet, there is a fast-flowing, narrow air current that winds its way around the top (and bottom — the southern hemisphere has a jet stream, too) of the earth.
The end result, for you as an air traveler, is that when you board that plane in Los Angeles (in the west) bound for New York (in the east), it’s going to take you about 30 minutes less to get there than it will for you to return home — thanks to the jet stream.