Abstract
The mainstream media and popular science platforms are rife with
misunderstandings about what a “polar vortex” is. The term most aptly
describes the stratospheric polar vortex, a single feature dominating
the cool-season circulation at ∼15–50 km altitude. Regional upper
tropospheric jet stream variations dominate the tropospheric
circulation, which is not well-described by the idea of a polar vortex;
indeed, there is no single consistent definition of a tropospheric polar
vortex in the literature. Stratospheric polar vortex disturbances
profoundly influence extreme weather events such as cold air outbreaks
(CAO). How the stratospheric polar vortex affects the tropospheric jets,
local excursions of which drive CAOs, is not yet fully understood. The
most public-facing parts of publications describing research on this
topic are sometimes unclear about how the “polar vortex” is defined;
greater clarity could help improve communications both within the
community and with non-specialist audiences.