What is the polar vortex that causes frost in North America?

Extreme weather breaks records in some US states 0:49

(CNN) --

In winter, low temperatures can intensify, creating weather conditions that create wind-chill weather conditions, so cold that they can even cause deaths and put millions of people on alert at once.

When these low temperatures hit North America, creating weather conditions like these, it's known as a polar vortex.

CNN International meteorologist Brandon Miller answers some pressing questions about this phenomenon.

What is a polar vortex?

What sets it apart?

The polar vortex is the circulation of strong upper-level winds that normally circle the North Pole in a counterclockwise direction.

These winds tend to keep icy air locked up in the arctic regions of the Northern Hemisphere.

The polar vortex is several kilometers high, about the distance that airplanes fly.

It is not a single storm, but a phenomenon that occurs all the time.

Sometimes this vortex becomes distorted and moves further south than you would normally find it, causing its frigid air to pour southward.

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How frequently does this distortion of the polar vortex occur?

The upper level winds that make up the polar vortex change in intensity from time to time.

When these winds decrease significantly, the vortex can become distorted and the result is a jet stream that plunges deep into the southern latitudes, carrying cold, dense arctic air downward.

This oscillation is known as the Arctic Oscillation.

When polar winds are weaker, they can cause bouts of cold air in one or more regions of the planet.

Where does this happen on Earth?

The polar vortex can give rise to large outbreaks of cold air anywhere in the Northern Hemisphere, whether in North America, Europe or Asia.

This can lead to cold snaps in multiple locations, although it doesn't always happen.

How dangerous is the distortion of a polar vortex compared to a tornado or hurricane?

They are completely different types of systems.

A bout of cold air caused by the polar vortex is much larger in area and duration than a single storm.

However, with the general drop in temperature, significant winter storms can develop, especially when cold air begins to penetrate a previously warm region.

If you get caught up in one of these distortions, what should you do?

It's not a storm you can get caught in, but if you're facing these significant cold temperatures, you should stay inside whenever possible, prepare your home and car for the cold, and wear multiple layers of clothing if you must go outside.

Is it a side effect of global warming or should we expect more events like this?

This is a highly researched topic.

In short, yes it could be.

It seems counterintuitive that global warming could cause significant cold snaps like this, but some studies show that it could.

We know that different types of extreme weather can result from global warming.

This includes extreme distortions of the jet stream, which can cause heat waves in summer and cold waves in winter.

polar vortex