At least 21 people have reportedly died as a result of the intense polar vortex gripping the Midwest of the US.
Freezing temperatures have shattered records across the region, with sub zero wind chills and snow keeping schools, businesses and government offices closed.
Iowa, Indiana, Illinois, Michigan, Minnesota and Wisconsin are the worst affected areas.
Chicago recorded all-time low temperatures of -29C yesterday – nearly 10 degrees colder than in 1985 – the previous record year.
A number of other cities also recorded record lows.
The Ahlstrom-Munksjo paper mill sends steam skyward during the polar vortex, Kaukauna, Wisconsin, USA, 30-01-2019. Image: USA TODAY Network/SIPA USA/PA Images
These people in Minnesota have been braving the elements.
“Layers – good layers – invest money in the really good stuff,” said one.
“It is pretty freezing,” said another. “Nothing that I haven’t been through before but it is all good; it is just part of living in Minnesota, we like it cold up here.”
Freezing clothing in a yard in Northeast Minneapolis, Minnesota, 29-01-2019. Image: Minneapolis Star Tribune/TNS/ABACA/ABACA/PA Images
The Chicago skyline is seen from Montrose Harbour, 30-01-2019. Image: Xinhua/Wang Ping
It is so cold that people across the region and into Canada have been experiencing “frost quakes” – with loud booms reverberating through cities.
The quakes – scientifically known as cryoseism – occur as a result of the sudden onset of extreme cold.
As the cold air pulls heat from the ground, the freezing temperatures leech deeper and deeper underground until they reach groundwater flowing through solid and rock.
When the groundwater freezes solid, the expanding ice puts intense pressure on the rock and soil causing it to suddenly crack, emitting a loud bang.
The noise is quite loud in the immediate area – however, it does not generally travel much further than a city block.
Firefighters at the scene of a house fire in St Paul, Minnesota. Image: David Joles/Minneapolis Star Tribune/TNS/Sipa USA
