From sciam https://twitter.com/sciam on Twitter: #: This week's deep freeze is being caused by the same mechanism behind the polar vortex that iced the Eastern U.S. in 2016. Learn why frigid air, normally bottled up at the North Pole, sometimes pours down as far south as Florida. https://blogs.scientificamerican.com/observations/what-is-this-polar-vortex-that-is-freezing-the-u-s/?utm_source=twitter&utm_medium=social&utm_campaign=sa-editorial-social&utm_content=&utm_term=sustainability_news_resurface&sf178110408=1 https://twitter.com/sciam/status/948901895690772482/photo/1 https://chirp.cooleysekula.net/attachment/46899