Professor Jennifer Francis , from the Institute of Marine and Coastal Sciences, Rutgers University, explained that the rapidly warming Arctic has created a ‘gentler’ atmospheric temperature gradient beetween the Tropics and the Poles. This leads to weaker, more variable, jet stream winds, which then ‘meander’ north and south more. This allows frigid polar air to penetrate further towards the tropics, and hot tropical air to penetrate further towards the poles. Also, because the wavy jet stream is moving more slowly, this causes weather systems to persist for longer.
5 fotogramas de Jonathan Demme 
28 minutes ago