Impact of a Winter Storm in the United States
A significant winter storm led to severe weather events from the Ohio Valley to New England on January 26, causing at least seven fatalities and affecting 17 states.
- Heavy snow, sleet, and freezing rain were reported, with more than a foot of snow accumulation in some areas.
- The storm caused a deep freeze, straining energy supplies and leading to widespread, prolonged travel disruptions.
- An estimated 157 million Americans faced cold temperatures ranging from sub-zero at the Canadian border to below-freezing conditions reaching as far south as the Gulf of Mexico.
The Polar Vortex
The winter storm was influenced by the polar vortex, a large area of low-pressure and cold air swirling around Earth's polar regions.
- There are two types of polar vortexes: tropospheric and stratospheric.
- The tropospheric polar vortex occurs in the lowest atmospheric layer (surface up to 10-15 km) where most weather phenomena occur.
- The stratospheric polar vortex occurs at 15-50 km high, disappearing during summer and strongest in autumn.
Polar Vortex and Extreme Cold
Extreme cold is experienced in the US, parts of Europe, and Asia when the polar vortex at the North Pole weakens and moves from its usual position.
- This movement can allow cold, arctic air to migrate south, impacting areas as far south as Florida.
- A strong polar vortex maintains the jet stream's circular path, which separates cold and warm air masses.
- When the polar vortex weakens, the jet stream becomes wavy, allowing cold air to push southwards.
Impact of Climate Change on the Polar Vortex
Researchers are investigating how climate change affects the polar vortex, potentially causing more frequent disruptions.
- As the poles warm faster than other parts of Earth, the polar vortex and jet stream may weaken.
- Warmer temperatures make the polar vortex more prone to disruption.
- Steven Decker, director of the Meteorology Undergraduate Program at Rutgers University, suggests that global warming decreases the strength of the polar vortex and jet stream, making them more susceptible to changes.
