Polar vortex is 'spinning backwards' above Arctic after major reversal event
Earlier this month, a sudden atmospheric warming event caused the Arctic's polar vortex to reverse its trajectory. The swirling ring of cold air is now spinning in the wrong direction, which has triggered a record-breaking "ozone spike" and could impact global weather patterns.
The polar vortex circling the Arctic is swirling in the wrong direction after surprise warming in the upper atmosphere triggered a major reversal event earlier this month. It is one of the most extreme atmospheric U-turns seen in recent memory.
In the past, disruptions to the polar vortex — a rotating mass of cold air that circles the Arctic — have triggered extremely cold weather and storms across large parts of the U.S..
The current change in the vortex's direction probably won't lead to a similar "big freeze." But the sudden switch-up has caused a record-breaking "ozone spike" above the North Pole.
The polar vortex is most prominent during winter months and extends into the stratosphere — the second layer of the atmosphere up to around 30 miles (50 kilometers) above the surface. The vortex spins counterclockwise with wind speeds of around 155 mph (250 km/h), which is around the same speed as a Category 5 hurricane, according to the U.K. Met Office. A similar vortex also encircles Antarctica during the southern winter.
Polar vortices occasionally reverse temporarily. These events can last for days, weeks or months and are caused by sudden stratospheric warming (SSW), when the temperatures in the stratosphere climb by as much as 90 degrees Fahrenheit (50 degrees Celsius) in the space of a couple of days, according to the Met Office.
Related: 'One of the biggest on record': Ozone hole bigger than North America opens above Antarctica
The sudden warming is caused by "planetary waves" in the atmosphere — compression waves formed when air rises into a region of different density and is pushed back downward by the force of Earth's spin. This process disrupts or reverses the vortex flow.
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The current reversal event in the Arctic began on March 4. However, the winds are starting to slow down, hinting that the vortex will return to its normal trajectory soon, Spaceweather.com reported.
"It was a substantial reversal," Amy Butler, a climate scientist at the National Oceanic and Atmospheric Administration (NOAA) and author of NOAA's new polar vortex blog, told Spaceweather.com. The speed of the reversed winds puts the event in the top six on record, she added.
Disruptions to the polar vortex can impact weather in the U.S., such as in 2019 when a massive cold front descended across the Midwest. These extreme weather events occur when the polar vortex deforms the jet stream — an air current that surrounds the polar vortex — exposing lower latitudes to large blobs of icy Arctic air.
This month's disruption did not change the shape of the jet stream, so weather patterns are expected to remain largely unaffected, according to Spaceweather.com.
However, the change in air temperature around the Arctic has sucked up large amounts of ozone from lower latitudes, creating a temporary ozone spike — the opposite of an ozone hole. Currently, there is more ozone surrounding the Arctic than at this time during any other year on record, according to Spaceweather.com. However, this ozone spike will disappear after the polar vortex returns to normal
The current reversal is the second of its kind this year, following a smaller event in January that did cause a brief cold snap in some states, Butler wrote in NOAA's polar vortex blog.
Historical records show that SSW events are more likely to occur during El Niño or La Niña, the two contrasting phases of a natural cycle of planet-wide warming and cooling. During these phases, global weather systems become more unstable, which sets the stage for more frequent reversal events, Butler wrote in the NOAA blog.
We are currently in the midst of a major El Niño, which could make further reversals or disruptions more likely over the next year or so.
Harry is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior, evolution and paleontology. His feature on the upcoming solar maximum was shortlisted in the "top scoop" category at the National Council for the Training of Journalists (NCTJ) Awards for Excellence in 2023.
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BenGates Either stop messing with weather modification, or fully embrace the potential. Feet of rain in the middle east, would be considered doing it wrong, but yet they keep overdoing the cloud seeding there for some reason. Like maybe dial back until you achieve the desired result. A deluge and flooded streets, cannot be the desired objective... frustrating thing to be toying around with, imo.Reply -
Giovani I originally considered the saturation of communications in the many reports of anomalies appearing on our planet.Reply
It is obvious we are entering a period of instability. I believe this phenomenon will increase, and it isn't confined to terrestrial environs.
A calamity of sorts may be forecast, not knowing the actual mechanics involved.
This makes a relevant posit.
The saying, "Murphys Law" is the human equivalent to what I'm describing. The current state of societies will not continue to function if this is the beginning of an active cycle, perhaps solar system wide. -
Jeremy Congratulations on writing the polar vortex reversal story in a non-alarming way that does not portend an irreversible global warming disaster. These things are obviously part of a natural cycle of things and tied to el-Nino and la Nina.Reply -
Jan Steinman
It's not going to be quick or simple to remove 1,470,000,000 motor vehicles from operation, which is how we're "messing with weather modification.BenGates said:stop messing with weather modification… frustrating thing to be toying around with…
But no worries. If we don't do it, nature will do it for us, probably removing us in the process, as well. -
TommyCarpenter It couldn’t have anything to do with a potential pole flip and the magnetic sphere weakening? I beat the date of the rotation switching is close to when we got hit by a solar flare.Reply -
Debed
Nah. The polar winds shifts about twice a year. That is why we get these ultra cold days now and then.TommyCarpenter said:It couldn’t have anything to do with a potential pole flip and the magnetic sphere weakening? I beat the date of the rotation switching is close to when we got hit by a solar flare.
Totally natural, has been happening for as long as humans know about.
So I am really not sure what this article is even trying to be about.
Fearmongering? -
CajunMoses
Dude, what are you talking about?BenGates said:Either stop messing with weather modification, or fully embrace the potential. Feet of rain in the middle east, would be considered doing it wrong, but yet they keep overdoing the cloud seeding there for some reason. Like maybe dial back until you achieve the desired result. A deluge and flooded streets, cannot be the desired objective... frustrating thing to be toying around with, imo.