Icy Arctic ‘vortex’ too cold for US polar bear
As freak weather sees North American temperatures plummet, climate change sceptics, who say ‘global weirding’ undermines climate science, face an online ban? Is this fair?
Across the American continent, schools and businesses are closed, 5,000 flights have been grounded and roads are blocked by snow. If that’s not sign enough of this week’s record-breaking iciness, a Chicago zoo has deemed the outside too cold even for its resident polar bear, who has joined many Americans by retreating indoors.
The daily workings of North America are being dramatically disrupted by the Polar Vortex, a whirlwind of extremely cold air that forms at the North Pole. Usually, these wind systems maintain a high speed, keeping the vortex stable and trapping the cold air over the Arctic. This time, however, the winds lost momentum, causing the cold air to spill southwards.
The freak 20 degree plummet in temperature has chilled the US and Canada below the Arctic’s relatively balmy -25ºC conditions. So officials have encouraged their communities (animals included) to stay indoors away from the treacherous -40ºC wind chill.
Finding reasons for why the Polar Vortex slowed down may have larger implications for the debate about climate change, because the peculiar behaviour of the Arctic winds was difficult to predict. Some scientists now describe such unexpected events as ‘global weirding’, where weather patterns are disrupted by complex shifts in the atmosphere.
Some even believe that these new phenomena threaten the confident consensus of climate scientists, who argue that a steady, long-term trend of warming in the Earth’s atmosphere is occurring, with some of it caused by humans burning fossil fuels. If so, ‘weirding’ would play into the hands of climate sceptics.
Now, Reddit, the popular online discussion site, has caused uproar by banning those who doubt the existence of climate change from commenting in its science forum. Typically a fierce defender of free speech, Reddit has drawn criticism for the move. But the site says a small minority of aggressive campaigners were making reasoned debate impossible.
Controversy hots up
First ‘global warming’, then ‘climate change’, and now ‘global weirding’? Climate sceptics argue that certainty on this topic is impossible: events like the New Year super-freeze in America offer proof of one fact only: that no one really knows what’s happening to the atmosphere.
So should recent errors in climate forecasts open up space for doubt? Not at Reddit, where moderators argue that the extremely complex debate about climate change has become overheated by the emotionally-charged arguments of the sceptics: pursuit of cold, hard, scientific truth should be carried out only by those who can keep cool heads. But others are uncomfortable or even angry about its decision, decrying such ‘censorship’: how can a major scientific discussion forum ban one side of such a significant argument?
- Is Reddit right to ban ‘aggressive’ online campaigners from science forums?
- Is there a place in scientific debate for climate scepticism?
- In groups, design an infographic to illustrate an aspect of climate change, such as ‘global weirding’.
- Imagine you are seeking shelter from a snowstorm. Write a letter describing what you saw during the sudden downfall.
Some People Say...
“You cannot kill an idea.’Medgar Evers”
What do you think?
Q & A
- There are big storms all the time!
- Exactly. But the frequency of large weather events has been increasing, prompting a fresh look into what causes them. There is no single answer, but the melting of the polar ice caps, caused by global warming, is a likely element. As the Arctic warms up, it disturbs the delicate temperature balance at the poles, potentially leading to cold snaps like this one.
- Global warming? This is a blizzard.
- True, but global warming doesn’t affect all of the planet in the same way. It comes down to the difference between weather and climate. Weather is what we see every day, from sunshine to snowfall. The climate works over a longer time period: measured over a hundred years, US winters have got warmer.
- Climate change
- The apparent phenomenon that the Earth’s climate is changing in temperature, weather patterns and gas composition, influenced largely by increased levels of atmospheric carbon dioxide.
- ‘Global weirding’
- A more chaotic understanding of climate change, linking unexpected weather patterns to human activity. Supporters of climate change theory say extreme weather events like this week’s ice-up are all part of the hazardous new environment brought about by humankind’s destructive rush to burn more and more fossil fuels.
- Fossil fuels
- Naturally occurring fuel sources that formed beneath the Earth’s crust many thousands of years ago, including oil. They release carbon dioxide when burnt, contributing to the greenhouse effect.
- Climate sceptics
- Those who dismiss the idea that the climate is changing in any meaningful or statistically significant way thanks to human activity.
- The self-described ‘frontpage of the internet’. Reddit is a social discussion website that covers thousands of topics. Although much of the site is dominated by memes, Reddit’s science forum offers the public the chance to discuss science with published academics.
- Global warming
- The gradual increase in the temperature of the Earth’s atmosphere, largely attributed to the greenhouse effect, in which the Sun’s warmth is trapped in the Earth’s atmosphere by the so-called greenhouse gases, including carbon dioxide.