Volume 17, Number 38: 17 September 2014
Paper Reviewed
Ballinger, T.J., Allen, M.J. and Rohli, R.V. 2014. Spatiotemporal analysis of the January Northern Hemisphere circumpolar vortex over the contiguous United States. Geophysical Research Letters 41: 3602-3608.
But was the circumpolar vortex over the contiguous United States in January 2014 really so unusual as to merit such attention and attribution? In a study designed to answer this question, Ballinger et al. analyzed pertinent data from all Januaries within the period 1948-2013. And what did they find?
First of all, the four U.S. researchers report that "the spatial features of the January 2014 USPV [United States Polar Vortex] were not extreme relative to certain 1948-2013 Januaries," as they note that the USPV of January 2014 only ranked as having "the sixth most southerly latitude, tenth most westerly longitude, and seventh largest area." Nor were the temperatures of the polar air the USPV brought with it ultra-extreme, as they say that the mean surface air temperatures of January 2014 were merely among "the coldest 10% of Januaries on record," as recorded within the 120-year history of the National Climatic Data Center (NCDC, 2014) archive for several Midwestern and Southern states.
And so we now know, as we have often noted about other exaggerated climate-alarmist claims, that there was nothing unusual, unnatural or unprecedented about the January 2014 circumpolar vortex over the contiguous United States, irrespective of all of the overblown media reports that accompanied it.
Reference
National Climatic Data Center. 2014. National Overview - January 2014.