Thursday, January 7, 2010

Waking Up To Northern Cold

A UK Met office graphic showing how "normal" weather in Europe has been usurped by a different system.

Europe is shivering beneath a blanket of snow. Yet it needs to be said. There is currently little evidence to suggest that the cold snap gripping the northern hemisphere has anything to do with global warming or climate change. But it is an excellent illustration of how sensitive we have become to even small changes. The current cold is nothing too serious or unknown. As I write this, Bloomberg reports that the year 2000 was colder than this winter, at least in Texas. In the UK, it’s the toughest winter in a generation, according to the New York Times. That’s 50 years.

Not such a serious winter, not so bad. For the baby boomers who wax lyrical about how they had real winters when they were kids, this is simply one of those “real” childhood winters. Normal then, even for people working and living today. But read the papers, the Eurostar is shut, airlines are grounded, natural gas is being shut off to factories and businesses, people are stranded, people are dying.

Hundreds have died. The Irish Times reports that thousands of schools are closed, gas supplies are dwindling, salt for roads is exhausted, and thousands of homes are without electricity.

Is this climate change? Funnily enough, temperatures are up all over the world. The British Meteorological Office reports that all over the world right now, outside of the northern hemisphere, temperatures are high. In some places by as much as 20 degrees Centigrade, many others by 5 to 10 degrees. It is only China, Russia, Europe and North America that are suffering from this cold snap. Strikingly, on the Met website, the following disclaimer appears at the bottom of the web page:
“The current cold weather in the UK is part of the normal regional variations that take place in the winter season. It doesn’t tell us anything about climate change, which has to be looked at in a global context and over longer periods of time.”

Local variations, short-term weather. That these are not related to climate change is so hard to explain to the mass majority of people. But look at broader areas of thought.

In the book Critical Mass, author Phillip Ball talks a lot about tipping points. He explains that systems operate in a certain, staid pattern, a pattern that can take a lot of tweaking, a lot of pushing, until a “critical mass” of change is reached (hence the name) at which point the system falters and then realigns itself into a different system.

An example of this is the stable system that provided warm water and warmer air to Europe for the last twenty years. Coming from the south and east, from the warm water of the Gulf Stream, otherwise known as the Atlantic thermocline, this warm air mass and the winds that flow from there were enough to keep the continent warm in the bitter cold of winter. But this year, that has changed.

In that change is something that even the staid Met office has acknowledged that says something about the current weather. Normally, the weather in Europe is dominated by a certain paradigm, now that paradigm is different. So if this stable system for the last two decades has changed, then lets extrapolate further.

The system that keeps Europe warm, that Atlantic thermocline, is in danger. The system brings warm water from the tropics up into the colder areas of Europe. The melt-water pouring off of Greenland’s ice sheet is possibly going to shut down this ocean heat conveyor, as part of the changes taking place due to human-induced climate change. It may fail, and if or when it does, Europe will look much like the western side of Alaska, un-warmed by such a conveyor: Cold, wet, frozen hard in winter. Inhospitable.

What is happening today is not necessarily part of that conveyor shutdown but it shows clearly, how a “normal” cold snap, part of a small tipping point, foreshadows the changes to come, and strips bare the true delicacy of our civilisation.

Our civilisation survives within a certain paradigm of climate, and as we push the critical thresholds of that paradigm by spewing greenhouse gases, cutting our forest sinks, and polluting our skies, we will, one day, pass that tipping point if we do not change our behavior.

No comments:

Post a Comment