Is This the Runaway?

This time everybody is sitting up and taking notice. Much of Europe is now colder than the high Arctic and it's in the middle of the blackout of winter.

People are looking to the north pole and asking if we're watching the onset of non-linear climate change, also known as runaway global warming.

While merry pictures of a snow-blanketed Vatican City were being broadcasted on every TV on the planet, an ominous thermometer reading was making every climatologist’s blood run cold. A few days ago, at Cape Morris Jesup, the northernmost land outpost in Greenland, the temperature reached 6° Celsius – without a minus sign – and saw a record-breaking 61 hours above freezing.

At the top of the world, there is no doubt left – climate change is palpably happening. Arctic sea ice is at its lowest level on record. During summer, cruise ships can sail unharmed through the famed Northwestern Passage. Greenland is melting at a much faster pace than previously thought. The Big North is warming twice as fast as anywhere else on the planet.

If climatologists have been tweeting messages of disbelief after the Cape Morris Jesup record temperatures, it is because they have a secret fear – that the Arctic’s fever could potentially trigger a non-linear response in the Greenhouse effect one indefinite day. Since the Industrial Revolution, the world has witnessed a linear and parallel increase in CO2 concentrations and mean ground temperatures. Yet it is thought that, above a certain warming threshold, a series of positive feedbacks could destabilise the atmospheric system. They call it ‘runaway climate change’. It is precisely what nobody, including deniers, would ever like to see.

This is the third or fourth year of mid-winter high Arctic heat waves, this year being the worst. If it does herald the arrival of runaway climate change that would mean that many of our worst-case scenario calculations have been wrong, unduly optimistic.

- sincere apologies to the Wilburys, especially Orbison, Harrison and Petty but also Lynne, Dylan and Keltner (drums).