What's in a Name? On the Use and Significance of the Term “Polar Vortex”

Abstract

This commentary appears in the Special Collection focusing on the Arctic stratospheric "polar vortex" in 2019/2020. But how clear are we about what constitutes a "polar vortex"? Confusion persists in the popular press about what a polar vortex is and how polar vortices relate to extreme weather events. This confusion stems in part from imprecise descriptions by the scientific community.In January 2014, a cold air outbreak (CAO) set record-low minimum temperatures throughout the south central and eastern US (e.g., Screen et al., 2015). Headlines hailed it as "the polar vortex," and this language became commonplace in news and popular science media. At the time, the term "polar vortex" in scientific literature typically described the stratospheric polar vortex (see, e.g., Lillo et al., 2021;Waugh et al., 2017, for discussion of this), but some studies used the term to describe the "tropospheric polar vortex" (e.g., Wallace et al., 2014;Yu & Zhang, 2015), in both cases often without further qualification. Waugh et al. (2017) sought to dispel confusion, describing the stratospheric and tropospheric "circumpolar" vortices as these terms had been commonly used in scientific literature, highlighting their differences and relationships to extreme weather events, and providing recommendations for describing them. While this work is widely cited, the two concepts are still often confused, including on educational websites and in climate change communication studies (e.g.,

Fluid Dynamics of Polar Vortices on Earth, Mars, and Titan

“…The term "tropospheric polar vortex" has a much more limited use in the scientific literature than that of "stratospheric polar vortex." However, following the extreme cold air outbreak over the United States in 2014, polar vortices have received a lot of attention in the mainstream media and popular science websites, which has resulted in increased usage in the scientific literature (see Manney et al 2022). There is some debate concerning whether consideration of a tropospheric polar vortex adds significant new insights to the traditional descriptions in terms of ridges and troughs, or in terms of waves propagating along the upper tropospheric jet stream (Waugh et al 2017, Manney et al 2022.…”

“…However, following the extreme cold air outbreak over the United States in 2014, polar vortices have received a lot of attention in the mainstream media and popular science websites, which has resulted in increased usage in the scientific literature (see Manney et al 2022). There is some debate concerning whether consideration of a tropospheric polar vortex adds significant new insights to the traditional descriptions in terms of ridges and troughs, or in terms of waves propagating along the upper tropospheric jet stream (Waugh et al 2017, Manney et al 2022. Manney et al (2022) suggested that salient features of the tropospheric circulation can most clearly be described in relation to the tropospheric jet streams, without invoking the term "tropospheric polar vortex."…”

“…There is some debate concerning whether consideration of a tropospheric polar vortex adds significant new insights to the traditional descriptions in terms of ridges and troughs, or in terms of waves propagating along the upper tropospheric jet stream (Waugh et al 2017, Manney et al 2022. Manney et al (2022) suggested that salient features of the tropospheric circulation can most clearly be described in relation to the tropospheric jet streams, without invoking the term "tropospheric polar vortex." This is likely true, and there is currently limited evidence for added value from consideration of a tropospheric polar vortex.…”

Introduction to Special Collection “The Exceptional Arctic Stratospheric Polar Vortex in 2019/2020: Causes and Consequences”

“…A commentary in this special collection (Manney, Butler, et al., 2022) discusses the uses and misuses of the term “polar vortex” in popular media as well as scientific literature. They argue that while this well‐established term accurately describes a well‐defined major feature that dominates the circulation in the polar winter stratosphere, attempting to use this term to describe the tropospheric circulation is misguided as that circulation is best characterized in terms of regional undulations of jet streams and the conventional language of ridges and troughs.…”

The “Polar Vortex” Winter of 2013/2014

“…However, no dates from the winter of 2013/2014 are included in the compendium of major SSW events (Butler et al, 2017;ESRL, 2020). These observations led to confusion in using the term polar vortex among scientists and in the media (ABC News, 2014;AIR, 2014;Manney et al, 2022;Waugh et al, 2017).…”