Jet Stream 'Traffic Jams' Drive Extreme Weather: Study

Did you get stuck in a traffic jam this morning? If so, you're in good company. Just like thousands of human drivers, planet Earth itself gets caught in a patches of bad traffic, a new study published in Science has revealed.

Scientists studying the behavior of Earth's weird jet streams have discovered the fast flowing currents of air bottleneck like vehicles on a busy road. These "traffic jams," they say, can cause extreme weather events.

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People pick up debris at Sandy Ground on the French Caribbean island of Saint-Martin in the wake of Hurricane Irma on September 18, 2017. Traffic jam-style atmospheric blocking can contribute to extreme weather. Helene Valenzuela/AFP/Getty Images

Jet streams are thin and winding currents of air that form in our planet's atmosphere. They meander across thousands of miles and interfere with local weather patterns through something called "blocking." This blocking can last for days, contributing to weird and sometimes intense weather events like the unexpected New Jersey landfall of Superstorm Sandy in 2012.

Sandy tore through the New Jersey coast, leaving thousands without a home. Five years later, many were still rebuilding their lives, reported in 2017.

Scientists charting jet streams noticed that atmospheric blocking patterns bear a "striking similarity" to the ebb and flow of congested traffic on a highway.

Read more: Why does a giant jet stream shooting around Jupiter suddenly reverse?

A well-established mathematical model helps researchers describe the behavior of traffic on a highway. In light traffic, cars usually drive near the speed limit and the flow of vehicles stays relatively smooth. When traffic becomes heavier, drivers slow down, disrupting the flow and causing bottlenecks as the density of traffic exceeds a highway's capacity.

Our planet's jet streams, the authors think, suffer similar traffic headaches. Stationary waves affect a jet stream's ability to produce transient waves. Local blocks form as streams reach their wave flow capacity, like cars slowing down and bottlenecking on a road.

Read more: Hurricanes are getting stronger rapidly, and experts predict 2018 season may be "above average"

Scientists believe that human-driven climate change is driving extreme weather, according to last year's National Climate Assessment. In the case of jet streams, the team reporting in Science suggest global warming might affect how often jet streams suffer a block. In the Pacific, for example, they think the frequency of blocks may actually be decreasing.

But, the response of jet streams to climate change, they write, is likely "non-uniform." For now it's hard to say exactly how these strange and powerful traffic jams in the sky will affect life down on the surface of Earth.