After a sudden warming in the upper atmosphere, the Arctic's polar vortex has undergone a major reversal, swirling in the opposite direction. This surprising atmospheric U-turn is one of the most extreme events witnessed in recent memory.

Arctic's Polar Vortex Swirls in Wrong Direction, Sparking Climate Concerns
1-9 January 2014. The full-disk images every 3 hours from GOES-WEST capture the sweep of a polar vortex that emerged from the arctic at the beginning of the new year, pushing a blizzard into the northeastern USA on January 3, followed by extensive bitter cold (-20 F, windchill -50 F) around the Great Lakes, and single digit temperatures as far south as Atlanta, Georgia.
(Photo : Wikimedia Commons/NASA Goddard Space Flight Center)

Unprecedented Polar Vortex Reversal in Direction

The polar vortex, a massive rotating mass of icy air encircling the Arctic, has recently experienced a significant reversal in its direction following an unexpected warming event in the upper atmosphere earlier this month.

Such reversals are rare and stand out as some of the most dramatic atmospheric shifts observed in recent memory. Historically, disturbances in the polar vortex have been known to trigger severe cold snaps and storms across large regions of the United States.

While the current reversal of the vortex's direction is not expected to result in a similar widespread deep freeze, it has caused an unprecedented surge in ozone levels above the North Pole.

The polar vortex, stretching into the stratosphere during winter months, rotates counterclockwise with wind speeds comparable to those of a Category 5 hurricane. A similar vortex phenomenon occurs over Antarctica during the southern winter, albeit less frequently observed.

These temporary reversals, known as sudden stratospheric warming (SSW) events, occur when stratospheric temperatures rapidly rise due to the formation of atmospheric compression waves. Despite the current reversal event beginning on March 4, indications of slowing winds suggest an imminent return to the vortex's typical trajectory.

Amy Butler, a climate scientist at the National Oceanic and Atmospheric Administration (NOAA), highlighted the event's significance, ranking it among the top six on record in terms of wind speed reversal. Butler noted that this current reversal marks the second occurrence this year, with a smaller event in January leading to a brief cold snap in certain states.

READ ALSO: Is The Polar Vortex Collapsing? Here's What It Means According to Experts

How Does It Affect Weather Patterns?

The polar vortex typically circulates the Arctic, intensifying in winter and diminishing in summer. Extending about 30 miles into the stratosphere with winds reaching speeds up to 150 mph, this counterclockwise-spinning phenomenon can significantly impact weather patterns in northern latitudes.

When the vortex is robust and stable, it keeps cold air confined to the Arctic region. However, disruptions can occur, allowing frigid air to spill into lower latitudes, as experienced during the severe cold snap of 2014.

Recently, since March 4th, the polar vortex has exhibited a rare reversal in direction, a phenomenon observed briefly in January as well. While this reversal is not expected to drastically alter weather patterns, it has led to an unusual spike in ozone levels around the Arctic.

Although vortex reversals can usher in cold weather, this particular event is not predicted to cause significant disruptions in North America. Instead, it is accelerating the transport of ozone from the tropics to the poles, resulting in heightened ozone levels in the Arctic.

However, experts anticipate that winds will revert to their usual westerly direction within 10 days, gradually restoring ozone levels to normal as the polar vortex resumes its typical behavior.

RELATED ARTICLE: Extreme Weather Events Linked to Global Warming and Anomalies in Polar Vortex

Check out more news and information on Polar Vortex in Science Times.