Ice coverage within the Arctic Ocean is presently the very best it has been since 2010 with help from the strongest polar vortex on the report.
Ice covers 5.4 million sq. miles of the Arctic – roughly the scale of America, Mexico, and India mixed. This protection remains to be beneath the long-term climate average; however, the uptick is a minimum of a brief stall in sea ice decline.
The elevated ice cowl in comparison with the last decade is because of a robust polar vortex.
The polar vortex is a spinning cone of low strain over the poles that are strongest within the winter months because of the elevated temperature distinction between the polar areas and the midlatitudes, the place the U.S. and Europe are positioned.
This is not like a storm you may consider within the decrease environment, with chilly and heat fronts producing rain or snow. As a substitute, the polar vortex happens primarily within the stratosphere, a layer of the ambiance about 6 to 30 miles above the bottom – above the troposphere, the place a lot of the climate with which you are acquainted happens.
When the polar vortex is strongest, chilly air is much less prone to plunge deep into North America or Europe (by strongest, we imply the commonly west-to-east move across the vortex is stronger than common).
Consider it as a wall – a stronger polar vortex helps block off chilly, arctic air from the midlatitudes. For a lot of this winter, the polar vortex has been sturdy and remained over the poles, the place the coldest air has been trapped for the previous few months.