Topics Covered: Important Geophysical phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc.
Polar Vortex Threatens To Send US, Europe Into Deep Freeze:
Meteorologists have predicted that the polar vortex, which is splitting into two and swirling southward, will send the US and European countries into a chilling deep freeze.
- Previously, such vortex Developed in 2014.
Polar vortex is losing stability and its splitting causes dramatic, extreme weather implications across the western nations such as the US and Europe. With a ‘disrupted’ polar vortex in 2021, the colder air is expected to spill out of the Arctic and result in the onset of extremely harsh winters.
What exactly is a polar vortex?
It is described as a whirling cone of low pressure over the poles that is strongest in the winter months due to the increased temperature contrast between the polar regions and the mid-latitudes, such as the US and Europe.
- The polar vortex spins in the stratosphere.
- Usually, when the vortex is strongest, cold air is less-likely to plunge deep into North America or Europe. In other words, it forms a wall that protects the mid-latitudes from cold Arctic air.
- But occasionally, the polar vortex is disrupted and weakens, due to wave energy propagating upward from the lower atmosphere. When this happens, the stratosphere warms sharply in an event known as sudden stratospheric warming, in just a few days, miles above the Earth’s surface.
- The warming weakens the polar vortex, shifting its location somewhat south of the pole or, in some instances, ‘splitting’ the vortex up into ‘sister vortices’.
Effects of Polar Vortex:
- The split higher up in the atmosphere can give rise to both, sudden and delayed effects, much of which involves declining temperatures and extreme winter weather in the eastern US along with northern and western Europe.
- A sudden stratospheric warming also leads to a warm Arctic not only in the stratosphere but also in the troposphere as well.
- A warmer Arctic, in turn, favours more severe winter weather in the Northern Hemisphere mid-latitudes including the eastern US.
- What is Polar Vortex?
- Where is it formed?
- Movement of winds in Polar Vortex.
What is Polar Vortex? Discuss
Sources: the Hindu.