It had then President Trump wishing for some ‘good old-fashioned global warming’ as an extreme cold front barreled into the Midwest. The plunging temperatures were cold enough to freeze exposed skin in 15 minutes and set cold temperature records in all 50 states. and the reason had its origin thousands of miles away. The deadly polar vortex intruded into the mid-latitudes, something that is becoming more common.
It was at the beginning of February this year when the snowstorm barged into the US northeast. Some areas experienced snows of over 2 feet. Spain had experienced something similar a few weeks before. Deadly snowstorms coupled with temperatures plunging dangerously low.
Even Northern Siberia experienced what by their standards was freezing. Temperatures went down to -70 F. the media announced the arrival of the vortex, making it out as something of ice spewing King Kong. But it is anything but an ice tornado or a snowstorm.
Polar Vortex: The Feared Winds Of Winter
The vortex doesn’t directly dump ice on us. But any disturbance in the vortex can trigger extreme cold weather conditions. This year it was the turn of the US to bear the brunt of the disruption.
Also read: Entire Ecosystems Can Collapse Within A Decade If Global Warming Goes Unchecked
The vortex was always there, an immense whirlpool of cold polar air and low pressure that surrounds both the North and South Poles. It always stays centered over the Arctic in the north, getting stronger in winter and weakening in summer.
The polar vortex has many eddies that get strong at times and extend down to the south. It shrinks in summer and moves poleward, and dips down towards the equator in winter. That is one of the reasons we have those big polar outbreaks in winter. It is the time when we are more likely to witness the polar vortex affect us.
We experienced this in January when one of those dips affected the US over the Midwest. This big outbreak of the cold wave affected transportation, flights, agriculture.
It affects every aspect of life and is an active area of research as to how this is linked to the process of global warming. This event was particularly severe. But even though it was very cold in the Midwest, other parts of the world experienced warm winters.
The counter-clockwise flow of air helps retain the colder air close to the Poles and is referred to as the vortex. The polar vortex expands at times during the winter in the Northern Hemisphere.
The polar vortex has always been there but has recently come under scrutiny. This enormous 3-dimensional expanse of wind stays between 10 and 30 miles above the surface of the planet, in the stratosphere.
The polar vortex moves in an easterly direction. Sustained winds easily exceed 100 miles per hour. Temperatures inside the vortex can plunge below minus 100 F in the winter nights in the polar region.
But then we need not worry about the polar vortex landing on our doorsteps. The influence it exerts is more indirect. Similar to a domino effect, any disturbance to the polar vortex sets off multiple events that culminate in freezing weather, as happened in Spain and the US this year.
The vortex varies in strength in the winter. These shifts cause changes in the position and strength of a fast-flowing stream of air up in the troposphere just under the vortex.
Called the jet stream, changes in this affect weather patterns around the world. Various areas of the planet experience either colder or even warmer weather, or drier or wetter conditions.
The Domino Effect Of The Vortex
The atmosphere of our planet is akin to one gigantic covering of air enveloping our earth and moving around fluidly. The vortex is linked to the weather patterns that move around the lower altitudes of the planet.
Normal changes in the weather and the fast-flowing jet stream can interrupt the arrangement of the polar vortex high up in the stratosphere. But normally, the vortex reverts to its customary size and shape, thus retaining the low temperatures and strong winds.
But at times the vortex is pushed off its perch by these jet streams and weather variations. This leads to distortion in its usual shape and temperatures, location, and winds.
This leads to the disruption in the structural reliability of the vortex. The repeated and prolonged occurrence of such an external disturbance can cause immense disruption, leading to the winds dying out and the warm-up of the vortex.
This is exactly what happens in the first months of this year. unexpected stratospheric warming disturbed the polar vortex significantly. This is a violent disturbance that weakens and distorts the polar vortex. It moves it away from the pole and even tears it apart.
The occurrence of such a disturbance causes a sudden and significant rise in the temperature at the poles by an incredible rate, spiking up to 90 F within a few days.
The domino effect has already been set in motion. The jet stream becomes affected by the sapped polar vortex flowing above and begins to rise and fall. This leads to warm weather in the far north and brings frigid cold weather patterns to the US and Europe. And the far north, on the other hand, experienced abnormally warm weather conditions.
It Gets Warmer Due To A Stronger Polar Vortex
Most weather systems in winter barely upset the vortex. This allows the polar vortex to generate faster winds and grow cold. This creates an opposite effect on the jet stream, trapping the frozen arctic air up north.
It caused exceptionally mild and warm winters in 2020 as the vortex was exceptionally strong. It becomes apparent that the vortex does not merely cause cold weather. It is also responsible for exceptionally warm weather conditions as in 2020.
For long periods, the polar vortex does not influence local weather patterns as it normally flows miles from the planet. But monitoring and forecasting significant disturbances in the patterns of polar vortex helps us anticipate future weather patterns that ultimately lead to severe cold conditions like the one that hit the US at the beginning of this year.
Keeping Watch On The Future
The effect of the polar vortex on climate change remains a concern given its ability to influence weather patterns around the globe. The Arctic region has been much affected by global change. In the past 3 decades, the region has warmed doubly fast when compared to the rest of the planet.
This phenomenon, known as Arctic amplification, has caused glaciers in the region to retreat and has also caused an alarming loss of ice in the Arctic sea. It is expected to upset the stability of the polar vortex, that scientists are yet to study its full implications.
Scientists feel that the warmer weather, that upsets the jet stream, and ultimately the polar vortex could be affected by the absence of ice in the Arctic region.
The loss of a significant quantity of ice would allow the sun to heat the Arctic waters. This gets released into the atmosphere and creates swellings of hot air in these sensitive regions.
These swellings can lead to making the northward movement in the jet stream stronger, larger, and even more persistent. This will in turn disrupt the vortex.
While 2016 and 2020 turned out to be the hottest years recorded, the decade has been the hottest in history. The ice cover over the Arctic has also come down to the lowest ever. But more research can shed light on the effect climate change is having on the weather forms flowing down each year from the Arctic region.
Also read: Climate Change Hits The Russian Arctic: Loses Billions Of Tons Of Ice Cover
Linking The Arctic Polar Vortex And Global Warming
The rise in frequency with which the polar vortex is dipping south from its perch over the Arctic is likely a result of climate change say, scientists.
The jet streams, the fast-moving band of air that form the outer limit of the polar vortex, are driven by the difference in temperature between the air in the mid-latitude regions and the air of the polar vortex. But the rising global temperatures are making the difference lesser. This has been the reason that the polar vortex is moving alternatively in the north and south directions.
The warmer temperatures have thus, a direct link to the strong polar vortex that is moving south with increasing frequency.
Scientists are studying the possibility that frequent interference from the polar vortex may be the reason that the effect of climate change is not being immediately felt in the mid-latitudes. With the polar vortex bringing colder than usual air to parts of Europe, the United States, and Asia, average temperatures are staying at normal levels in many areas of these regions.
Global Temperature Rise Doesn’t Have To Be Uniform To Be Declared Global Warming
Localized weather conditions do not represent the planet. Winters do exist and the cold can be severe, aggravated by conditions created by global warming.
The past 4 years have been the hottest on record. Record temperature rise in the US has been outnumbering lows by 2 to 1. This ratio will expand to 16 to 1 if there is a rise of 5.4 F, a likely occurrence if greenhouse gases are not curtailed. While certain politicians mock climate change for their political ends, the fact remains that we are in for a hotter planet in the not-so-distant future.
