How Arctic Amplification Affects the Polar Vortex

How Arctic Amplification Affects the Polar Vortex


Over the past few decades, the surface air temperature of the Arctic region has been warming at a rate twice as fast as the global average. Accelerated Arctic warming is in part due to melting
Arctic sea ice and snow cover. The region has also seen greater trends and variability
in the ecosystem than the rest of the Northern Hemisphere. This phenomenon is known as Arctic amplification,
and it’s strongest in autumn and winter. To explain how Arctic amplification affects the polar vortex, let’s start by looking at the vortex in its stable — or strong — state. During the winter months, the polar vortex is a wide
expanse of fast-swirling cold air, flowing west to east in the stratosphere around an area of
low pressure centered on the North Pole. Picture this area of low pressure as a bowl-shaped
indentation of the stratosphere filled with cold air particles, shown here as blue dots. The heaviest and most dense of these cold air particles settle in the bottom of the bowl, weighing it down. When the vortex is strong, the cold air is confined inside the bowl, and the jet stream in the troposphere below it flows in a
fairly regular path around the globe. Think of the jet stream as essentially dividing the cold air
up north and the warm air down south. The large temperature difference keeps the jet stream
on a straighter path. And weather patterns and storm tracks tend to be
fairly normal and seasonable. During Arctic amplification, the increasingly warm air in the Arctic causes a kink in the jet stream over Eurasia. This sends warm air particles, shown here as red dots, into the bowl-shaped indentation from the sides, pushing towards its center and weakening the polar vortex. The hot air causes the pressure to rise over the North Pole,
eventually inverting the shape of the bowl. During this redistribution of air masses, the cold air particles
are displaced by the warmer air, rolling off and spilling away from the North Pole to the outer layers
of the atmosphere in the midlatitudes. In more extreme disruptions, the polar vortex splits into two daughter vortices. In this weakened state, air flows in a wavier fashion around the Arctic, meandering north and south, rather than flowing steadily west to east — and the redistribution of cold and warm air accelerates. The reduction in the temperature and pressure
difference between the Arctic and the tropics robs the jet stream of some of its strength, causing it to meander — sometimes dramatically —
to the north and south along its path. These large swings in the jet stream allow cold air to push further than usual into the southern portions of the hemisphere, creating weather events like Arctic air outbreaks and severe snowstorms, and warm air to penetrate deep into the Arctic, resulting in unusual Arctic “heat waves.” The profound changes to the Arctic system have coincided with a period of more frequent extreme weather events across the Northern Hemisphere’s midlatitudes. The potential link between Arctic amplification and changes in extreme weather is a critical one, as this phenomenon can be expected to continue over the coming decade.

11 thoughts on “How Arctic Amplification Affects the Polar Vortex

  1. I don't think that the explanation given here is correct but I'd need to listen to a thorough explanation by an atmospheric physicist before I could ponder it further and reconcile my objections to this explanation.

  2. Well, you have to give the public some kind of excuse for why they're freezing to death when you tried to scare them about the world getting too warm.

  3. That explanation of the effect is pretty clear… but that does not suggest a cause of this phenomena being triggered in the first place. Would it be fair to ask what part you though the HAARP generators in Alaska and other parts of the world might be playing in this scenario.

  4. Okay, after reading some of the comments it appears that there is a thirst for more information. So, "cause & effect." There has been multiple, complicated processes of Arctic Amplification that will adversely affect our backyard in the Northern Hemisphere. In this case, a December 31, 2018 Sudden Stratospheric Warming (SSW) event resulted in a Polar Vortex Split (Not a Polar Vortex Disruption or a "wobble" in the Polar Vortex). In early January 2019, Climatologist communicated a forecast that we can expect four to 8 weeks of intense, recurrent wintry weather events. They were right, two months of it. If an individual has not taken college level Physics, Chemistry, Biochemistry or Geology, then Global Climate Change is fundamentally unreal for them. I understand that, but it doesn't make Global Climate Change is unreal. A person may debate, lobby for or against an idea or put a political spin on attribution study results, (BUT) one cannot debate, set conditions or alter the basic laws of Physics or the laws of Chemistry. More recently, the Catastrophic flooding in the Midwest: "cause & effect" is simply an example of the Clausius/Clapeyron Relationship (equation) forecasting the moisture holding capacity of the atmosphere is increased by ( about, the equation is not linear ) 7% for every 1 degree Celsius average global temperature rise. Where it has rained before, it will flood. This is not a fluke, it is a trend. And people need to start talking about it…like the "Mystery" of the untaxed negative externalities of our fossil fuel energy companies have enjoyed for decades.

  5. This process is a confusing/ complex enough process to explain, and I think this graphic (specifically the graphic/ video) is inaccurate, thus making it more confusing. A surge of warm air from the TROPOSPHERE ("surface") moves poleward, and then UPWELLS into the arctic stratosphere, thus displacing the "bowl" of cold stratospheric air & subsequently the polar vortex. In the video, you show everything just kind of doing a shuffle and it doesn't really make sense, especially when the red dots (warm air) in the STRATOSPHERE just randomly move over the pole, which doesn't happen.

  6. Wait— what are these “air particles” of which you speak?
    Why are some of them big dots, and other “air particles” are smaller dots?

  7. Face it, the world governments are panicking as we sink into a cold period. Spin the fraud to get as much traction as possible. The UN will soon be discredited.

  8. I think the Sun is to blame for polar jet weakness or it's movement into the southern latitudes…The Sun is entering a grand minimum which will help reduce higher temps caused by global industry, cars etc…basically we are polluting ourselves terribly. Mankind is shitting where it eats. SMH.

  9. Great video for people who (like me) are disinclined to slog through the journal articles. So the positive amplification is when the pressure increases in the polar region, and the negative amplification is the steady state? Is this the same as saying the Arctic Oscillation is positive?

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