Donald Trump has erroneously cited an enormous winter storm that is set to deliver freezing temperatures and heavy snow to half of the US as supposed proof that the world is not heating up due to the burning of fossil fuels.
Trump, who has repeatedly questioned and mocked established climate science in the past, posted of the storm on Truth Social: “Rarely seen anything like it before. Could the Environmental Insurrectionists please explain – WHATEVER HAPPENED TO GLOBAL WARMING???”
The winter storm will surge from the Rockies across the midwest and southern US on Friday, ending up on the east coast over the weekend. At least 230 million people are expected to be affected in some way by the storm with roads set to become dangerously icy and power blackouts expected in multiple locations.
This storm is being caused by a mass of frigid air from the Arctic hitting warmer, moister air in the US. Colder Arctic air is usually confined to the far northern latitudes by the polar vortex, a vast circular ribbon of wind. When the polar vortex weakens or stretches out, the freezing Arctic air can spill out south into the US, a bit like when you open the front door on a very cold day. This is what is happening now.
Research published last year found that the stretching of the polar vortex in this way is contributing to extreme weather in the US and that global heating, counterintuitively, could be playing a role in accelerating this process.
The Arctic is heating up as much as four times as quickly as the rest of the planet, with these elevated temperatures causing a series of knock-on impacts that may be altering the polar vortex. For example, the loss of sea ice in the Arctic region is amplifying the heating that can lead to these polar vortex disruptions.
Also, scientists point out that a single winter storm in one region of one country tells us very little about longer-term, global climate trends. Not only is the world undeniably heating up, in countries like the US winters are warming at a faster rate than other seasons, causing the loss of glaciers and the shifting of seasonal norms.
Even amid the current winter storm, parts of the western US have been affected by a severe lack of snow, which has hamstrung many ski resorts. Longer term, the trend is clear – winter cold snaps have got shorter, by six days on average, across much of the US since 1970, according to Climate Central, a research non-profit.
Cold days are still occurring but are being significantly outnumbered by record hot days. Across the US, since 1970 there has been an average temperature rise of at least 2.5C (4.6F) in the coldest temperatures people experience each year.