It happened before humans dumped billions of tons of carbon dioxide into the atmosphere and will happen again.
This polar vortex excursion is a single weather event directly affecting about 2 percent of the world.
Climate change is measured by evaluating continental to global trends in weather over decades – not events happening over a few days in a little region. For this reason, a fleeting cold wave (or snowstorm) over part of a continent should never be used as evidence for or against climate change.
The record shows winter temperatures have risen markedly in recent decades across the northern hemisphere.
In short, climate change has reduced the intensity/frequency of cold extremes averaged over time. But that doesn’t mean they’re over or have been eliminated. Events like the record cold in Europe in 2011 and this polar vortex event are clear examples of the exceptional cold weather extreme in a warming world.
(Were it not for the build-up of manmade greenhouse gases in the atmosphere, I’d posit the extreme cold events we witness now would be even colder. In other words, take these same cold air outbreaks and project them on the climate of the 1800s, and they’d be more severe. We’d need a model to test that, but it’s an educated guess.)
The truth is that increasing greenhouse gases act to warm the globe and, on average over time, should take an edge off the cold. But the planet is a really big, complicated place and the weather changes fast and randomly. Conversely, the climate changes very gradually. Taking all of this together, cold shouldn’t come as a shock, nor should it have anyone second-guessing the reality of climate warming.