A term we have all became very familiar with over the past two weeks, "Polar Vortex". But what is it, and how does it affect the weather?
The polar vortex is not something new or is it something that just forms and goes away. It is a large circulation in the upper atmosphere that has generally west-to-east winds circling the Earth. It's not a cold wave or a storm. It is there 24/7, 365 days a year, just not as prominent in the summer months. What it does do is usually causes really cold temperatures at the surface, which was seen in the eastern half of the country last week. It is usually centered near the northern pole of earth, but a piece of it broke off and moved south bringing cold arctic air with it. This piece moved slowly from the northern plains, through the great lakes and then moved north from the east coast.Image on left is unusual and was seen this past week, image on right is more of a typical pole set up.
Scientists feel this may become more typical due to warming global temperatures. Warmer air allows the polar vortex to break down easier and the little pieces of it can then travel south into highly populated areas. Places in the mid latitudes like New York, Chicago and Minneapolis could see harsher winters because of warmer summer temperatures breaking down the arctic sea ice. For more on the polar vortex and how it affected the country in the first week of 2014, here is an article by NOAA (National Oceanic and Atmospheric Administration). Click here for article.