Scientists still can’t yet say how a massive warming in the stratosphere above the North Pole will affect our weather.
After reaching near-record lows in early January, temperatures in the Arctic stratosphere—the layer of the atmosphere above the troposphere, where we all live—are rapidly rising due to what’s known as a sudden stratospheric warming (SSW) event.
Temperatures in the stratosphere have already soared – jumping up to 50 degrees this week, and scientists fear the event is disturbing the polar vortex. Keep in mind that the polar vortex is an area of low pressure across the North Pole that forms within the stratosphere during autumn, as temperatures plummet in the absence of solar radiation.
The SSW event could have major implications for weather patterns across the northern hemisphere in March. These SSW events are very common and occur two in every three winters.
The Guardian explains – As the polar vortex develops during autumn and into winter, westerly stratospheric winds increase in strength. But during an SSW event, stratospheric temperatures rise rapidly in the space of only a few days, leading to the weakening or even reversal of these winds.
And that is exactly what happened on February 15th. The winds turned to an easterly direction significantly displacing the polar vortex away from the North Pole. The vortex and zonal winds are forecast to stay much weaker than normal for the remainder of February and into the first half of March.
This will be the fourth such event in the last six years, a frequency that matches what we’ve seen over more than six decades of stratospheric observations, according to Climate.gov.
Climate scientists are not certain of what will happen with the weather in our troposphere, but sometimes these events lead to extremely cold air outbreaks in the mid-latitudes of the United States.
There has been some speculation that this latest event could topple the first domino in a chain reaction that would reshuffle weather patterns. For instance, the eastern U.S. has seen an exceptionally mild January and February and some previous sudden stratospheric warming and polar vortex disruptions have precipitated extreme cold snaps and severe winter storms.
The last time a sudden stratospheric warming event occurred was on Jan. 5, 2021. Just over a month later, according to the Washington Post, the most dramatic cold air outbreak since 1989 plunged the central U.S. into a historic deep freeze, causing the collapse of Texas’s power grid, claiming at least 330 lives and incurring more than $27 billion in damages.
