Would you like to subscribe to our newsletter?

Kamloops News

THOMPSON: The role jet streams play in weather and air travel

February 05, 2024 - 12:00 PM



Ask someone what they know about the jet stream and after a quizzical look, they’re apt to answer your question with a question-like “that’s the wind that speeds up or slows down jets, right?”

It - or more precisely they - do, indeed, affect jets flying across the globe. But jet streams do much more. Specifically, the polar-front and subtropical jet streams largely control our weather. These jet streams form and intensify when cold air meets warm air.

The resulting winds - typically 80 to 140 mph - always flow West to East in the Northern Hemisphere…with the jet stream in the Southern Hemisphere mostly circling Antarctica.

Jet stream wind speeds can occasionally reach 275 mph. I caught such a strong tailwind flying on a red-eye to France one time…arriving in Lyon almost two hours early…not even the customs officials were working.

Jet streams are strongest during Winter months…when the temperature differences forming them are greatest. These high-level wind currents exist between five and nine miles above the Earth’s surface and are in a more or less constant state of change.

They move to higher and lower altitudes, and sometimes even break up, depending on the season…even the sun can affect them. During colder months the jet streams move toward the Equator…returning toward the poles in Spring.

Beyond these changes, climate change is shaking things up with jet streams…and that doesn’t bode well for future air travel…and more importantly…our weather.

When jet streams change dramatically…shifting or breaking apart…funny things - as in peculiar - happen with our weather. They can make hurricanes come ashore in Northern states and provinces or bring killer freezes to Florida.

As you might expect, global warming - a real thing despite political resistance - is happening at the poles more than elsewhere around the world…about four times faster than the tropics, according to science.

Greenland lived up to its name 56 million years ago when volcanoes dotted the land during a sudden climate change. Back then rising sea levels didn’t endanger much coastal populations. But if the ice of Greenland all melted today…the world’s oceans would rise 23 feet.

Scientific studies indicate that as jet streams become more erratic as Earth warms, weather events like torrential rains could stay over areas for weeks. Floods will become common where there haven’t been floods.

While Winters are actually trending toward warmer temperatures in North America over time…it’s still possible to get record cold Winter temperatures, according to scientists. When a jet stream breaks, a polar vortex pushes a low-pressure area South in the Northern hemisphere…causing record cold temperatures.

This not only confounds some feeds the never-ending appetite of conspiracy theorists who contend global warming is a high-level plot involving scientists worldwide.

Scientists continue to study jet streams…trying to gage how jet stream changes will further impact our weather. We have learned that increasingly so-called “jet streaks” - super high-speed winds - actually exist inside jet streams.

Research by the University of Chicago and the U.S. National Science Foundation National Center for Atmospheric Research reports that “the fastest upper-level jet stream winds will accelerate by about 2% for every degree Celsius (1.8 degrees Fahrenheit) that the world warms.”

The fastest winds - those “jet streaks” - will speed up 2.5 times faster than the average jet stream wind, scientists say, adding that instances of clear air turbulence and rough rides are increasing…and will likely continue.

Over the past five years, several commercial jets have attained speeds exceeding 800 mph crossing the Atlantic Ocean from the U.S. to Europe. These flights also experienced increased turbulence in these “jet streaks”.

The jet streams will continue to play a huge role in air travel and weather…and the changes might not benefit us as much as in the past.

An old proverb says, “forewarned is forearmed”…perhaps.

— Don Thompson, an American awaiting Canadian citizenship, lives in Vernon and in Florida. In a career that spans more than 40 years, Don has been a working journalist, a speechwriter and the CEO of an advertising and public relations firm. A passionate and compassionate man, he loves the written word as much as fine dinners with great wines.

We welcome your comments and opinions on our stories but play nice. We won't censor or delete comments unless they contain off-topic statements or links, unnecessary vulgarity, false facts, spam or obviously fake profiles. If you have any concerns about what you see in comments, email the editor.

News from © iNFOnews, 2024

View Site in: Desktop | Mobile