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‘Polar vortex event’ brings subzero temps to U.S. — and it could become more common.
On Wednesday, Chicago was colder than parts of Antarctica by 10 degrees Fahrenheit.
- Cold Arctic air will bring temperatures near or below zero degrees Fahrenheit for more than 100 million Americans.
- A disruption in the swirling mass of air above the Arctic Circle – a pattern known as the polar vortex – is causing this weather event.
- Although counterintuitive, it's possible that global warming leads to these kinds of disruptions.
A huge mass of Arctic air is sweeping across the U.S., bringing subzero temperatures that have grounded flights, closed schools and killed at least two so far.
Temperatures are lowest in the Midwest and New England, where about 25 million people are projected to face temperatures of minus 20 degrees Fahrenheit, with wind chills of around minus 60 in parts of Minnesota and North Dakota. On Wednesday morning, Chicago was colder than Antarctica by 10 degrees at minus 21.
"The heart of the Arctic cold has arrived," the National Weather Service's Chicago office said on Twitter. "The combined effects of the cold & winds are at their peak today with wind chills of -45° to -60° continuing. The afternoon highs today...yes the highs...will only be -11° to -17°."
Only 5 to 10 minutes...that's all it takes to get frostbite in this frigid weather. #WinterSafety https://t.co/UUE6BdIRQ5— NWS Des Moines (@NWS Des Moines)1548785700.0
Nationwide, at least two people have been confirmed dead and thousands of flights have been cancelled.
"You're talking about frostbite and hypothermia issues very quickly, like in a matter of minutes, maybe seconds," Brian Hurley, a meteorologist with the Weather Prediction Center, told the Huffington Post.
A polar vortex event
The frigid temperatures are caused by a mass of cold air that leaked from the polar vortex in the Arctic Circle. The polar vortex is an area of cold, low-pressure air that swirls in the stratosphere above Earth's North and South poles. When it's strong, the polar vortex swirls in a regular pattern above the Arctic Circle, contained in part by a strong jet stream that keeps the cold air up north and the warm air down south.
But sometimes the winds that power the polar vortex weaken, resulting in a destabilized jet stream that shoots cold air to the south – what's known as a polar vortex event.
Although the polar vortex isn't new, scientists still aren't exactly sure what factors destabilize it and cause these extreme weather events. In recent years, however, some climate scientists have suggested that global warming might be causing disruptions above the Arctic.
Does global warming cause polar vortex events?
Possibly. Although it seems counterintuitive that global warming might cause subzero temperatures, it's known that warm air can weaken the polar vortex. So, considering that the Arctic is warming at faster rates than the rest of the planet, it's possible that global warming is disrupting the polar vortex above the North Pole, resulting in a weakened jet stream – the barrier that keeps the frigid Arctic air contained in the north.
To be sure, this theory is still being researched by climate scientists, and what exactly causes polar vortex events is still an open question, as Dr. Michael Mann, the director of the Earth System Science Center at Pennsylvania State University, told CBS News:
These questions test the limits of both our available data (the apparent increase in frequency of these events is quite recent and so at best only just starting to emerge from the background noise) and the model simulations.
As we showed in our recent Science article, current generation climate models don't resolve some of the key processes involved in the jet stream dynamics behind many types of weather extremes.
Honest scientists can legitimately differ based on reasonable interpretations of the evidence to date.
- Texas snowstorms due to rapid heating of the Arctic, say scientists - Big Think ›
- Texas snowstorms due to rapid heating of the Arctic, say scientists - Big Think ›
- What's causing the snowstorms in Texas? - Big Think ›
A man's skeleton, found facedown with his hands bound, was unearthed near an ancient ceremonial circle during a high speed rail excavation project.
- A skeleton representing a man who was tossed face down into a ditch nearly 2,500 years ago with his hands bound in front of his hips was dug up during an excavation outside of London.
- The discovery was made during a high speed rail project that has been a bonanza for archaeology, as the area is home to more than 60 ancient sites along the planned route.
- An ornate grave of a high status individual from the Roman period and an ancient ceremonial circle were also discovered during the excavations.
Foul play?<p>A skeleton representing a man who was tossed face down into a ditch nearly 2,500 years ago with his hands bound in front of his hips was dug up during a high speed rail excavation.</p><p>The positioning of the remains have led archaeologists to suspect that the man may have been a victim of an ancient murder or execution. Though any bindings have since decomposed, his hands were positioned together and pinned under his pelvis. There was also no sign of a grave or coffin. </p><p>"He seems to have had his hands tied, and he was face-down in the bottom of the ditch," <a href="https://www.livescience.com/iron-age-murder-victim-england.html" target="_blank">said archaeologist Rachel Wood</a>, who led the excavation. "There are not many ways that you end up that way."</p><p>Currently, archaeologists are examining the skeleton to uncover more information about the circumstances of the man's death. Fragments of pottery found in the ditch may offer some clues as to exactly when the man died. </p><p>"If he was struck across the head with a heavy object, you could find a mark of that on the back of the skull," Wood said to <a href="https://www.livescience.com/iron-age-murder-victim-england.html" target="_blank">Live Science</a>. "If he was stabbed, you could find blade marks on the ribs. So we're hoping to find something like that, to tell us how he died."</p>
Other discoveries at Wellwick Farm<p>The grim discovery was made at Wellwick Farm near Wendover. That is about 15 miles north-west of the outskirts of London, where <a href="https://www.hs2.org.uk/building-hs2/hs2-green-corridor/" target="_blank">a tunnel</a> is going to be built as part of a HS2 high-speed rail project due to open between London and several northern cities sometime after 2028. The infrastructure project has been something of a bonanza for archaeology as the area is home to more than 60 ancient sites along the planned route that are now being excavated before construction begins. </p><p>The farm sits less than a mile away from the ancient highway <a href="http://web.stanford.edu/group/texttechnologies/cgi-bin/stanfordnottingham/places/?icknield" target="_blank">Icknield Way</a> that runs along the tops of the Chiltern Hills. The route (now mostly trails) has been used since prehistoric times. Evidence at Wellwick Farm indicates that from the Neolithic to the Medieval eras, humans have occupied the region for more than 4,000 years, making it a rich area for archaeological finds. </p><p>Wood and her colleagues found some evidence of an ancient village occupied from the late Bronze Age (more than 3,000 years ago) until the Roman Empire's invasion of southern England about 2,000 years ago. At the site were the remains of animal pens, pits for disposing food, and a roundhouse — a standard British dwelling during the Bronze Age constructed with a circular plan made of stone or wood topped with a conical thatched roof.</p>
Ceremonial burial site<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzMTk0Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NDgwNTIyMX0.I49n1-j8WVhKjIZS_wVWZissnk3W1583yYXB7qaGtN8/img.jpg?width=1245&coordinates=0%2C82%2C0%2C83&height=700" id="44da7" class="rm-shortcode" data-rm-shortcode-id="46cfc8ca1c64fc404b32014542221275" data-rm-shortcode-name="rebelmouse-image" alt="top down view of coffin" data-width="1245" data-height="700" />
A high status burial in a lead-lined coffin dating back to Roman times.
Photo Credit: HS2<p>While these ancient people moved away from Wellwick Farm before the Romans invaded, a large portion of the area was still used for ritual burials for high-status members of society, Wood told Live Science. The ceremonial burial site included a circular ditch (about 60 feet across) at the center, and was a bit of a distance away from the ditch where the (suspected) murder victim was uncovered. Additionally, archaeologists found an ornately detailed grave near the sacred burial site that dates back to the Roman period, hundreds of years later when the original Bronze Age burial site would have been overgrown.</p><p>The newer grave from the Roman period encapsulated an adult skeleton contained in a lead-lined coffin. It's likely that the outer coffin had been made of wood that rotted away. Since it was clearly an ornate burial, the occupant of the grave was probably a person of high status who could afford such a lavish burial. However, according to Wood, no treasures or tokens had been discovered. </p>
Sacred timber circle<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzUzMTk0Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2MDAwOTQ4Mn0.eVJAUcD0uBUkVMFuMOPSgH8EssGkfLf_MjwUv0zGCI8/img.jpg?width=1245&coordinates=0%2C149%2C0%2C149&height=700" id="9de6a" class="rm-shortcode" data-rm-shortcode-id="ee66520d470b26f5c055eaef0b95ec06" data-rm-shortcode-name="rebelmouse-image" alt="An aerial view of the sacred circular monument." data-width="1245" data-height="700" />
An aerial view of the sacred circular monument.
Photo Credit: HS2<p>One of the most compelling archaeological discoveries at Wellwick Farm are the indications of a huge ceremonial circle once circumscribed by timber posts lying south of the Bronze Age burial site. Though the wooden posts have rotted away, signs of the post holes remain. It's thought to date from the Neolithic period to 5,000 years ago, according to Wood.</p><p>This circle would have had a diameter stretching 210 feet across and consisted of two rings of hundreds of posts. There would have been an entry gap to the south-west. Five posts in the very center of the circle aligned with that same gap, which, according to Wood, appeared to have been in the direction of the rising sun on the day of the midwinter solstice. </p><p>Similar Neolithic timber circles have been discovered around Great Britain, such as one near <a href="https://bigthink.com/culture-religion/stonehenge-sarsens" target="_blank">Stonehenge</a> that is considered to date back to around the same time. </p>
Research reveals a new evolutionary feature that separates humans from other primates.
- Researchers find a new feature of human evolution.
- Humans have evolved to use less water per day than other primates.
- The nose is one of the factors that allows humans to be water efficient.
A model of water turnover for humans and chimpanzees who have similar fat free mass and body water pools.
Credit: Current Biology
Being skeptical isn't just about being contrarian. It's about asking the right questions of ourselves and others to gain understanding.
- It's not always easy to tell the difference between objective truth and what we believe to be true. Separating facts from opinions, according to skeptic Michael Shermer, theoretical physicist Lawrence Krauss, and others, requires research, self-reflection, and time.
- Recognizing your own biases and those of others, avoiding echo chambers, actively seeking out opposing voices, and asking smart, testable questions are a few of the ways that skepticism can be a useful tool for learning and growth.
- As Derren Brown points out, being "skeptical of skepticism" can also lead to interesting revelations and teach us new things about ourselves and our psychology.