“It’s beyond shocking,” David Phillips, a senior climatologist with Environment Canada, told Canwest News Tuesday. Records have been shattered from “coast to coast to coast.”

“It is truly a remarkable situation,” says Phillips, noting that he’s seen nothing like it in his 40 years of weather watching. He also warns that “the winter than wasn’t” may have set the stage for potentially “horrific” water shortages, insect infestations and wildfires this summer.”

Well, if you live in the Northern Hemisphere, you’ll have noticed it’s colder than usual. Some countries have been turned white for several weeks with snow falling, but not melting at all. In the Netherlands, where I live, the entire country seemingly stopped moving for a few days before Christmas, both enchanted by the winter wonderland, and having roads and train tracks completely blocked by the snow.

This has been going on for about a month, which is an unusually long time for us to bear the inconvenience and disruption which results, but an extremely short period on the time scale with which climate is analysed – one point on the charts, which, against a perpetual background of natural variation, are nonetheless showing an ongoing upward trend over time-scales of years to decades. The current cold snap is part of that natural short-term fluctuation which we will always face, even in a future world which, on the basis of global, long-term averages, may be much warmer than present. And while it might seem that the entire globe is caught in its icy grip, it is actually a far more regional phenomenon than might immediately be apparent.

The extreme cold weather has been caused by an extremely interesting (yet not so well understood) weather pattern called the Arctic Oscillation. Simply put, a pattern of high atmospheric pressure over Greenland and parts of the Arctic has been blocking the usual pattern of much milder south westerly winds from the Atlantic and instead sending cold northerly and easterly winds to lower latitudes from the Arctic and the northern European land masses. At the same time, however, this same high pressure system has been causing much higher temperatures than usual in parts of the Arctic, but since population density is obviously much lower there, we haven’t heard as much about these. Furthermore, during the last week of December when the cold weather across Europe began to take hold, many parts of the North East USA and Canada, as well as North Africa, the Mediterranean and large areas of South West Asia were a good few degrees warmer than usual, up to 10 degrees Celsius warmer in parts of Northern Canada.

Despite the Arctic Oscillation being a known (if unpredictable) weather pattern, this hasn’t stopped would-be witty headlines all over the world, wondering what happened to global warming, worrying we are now entering global cooling etc. – all more designed to attract readership and page views than to reflect scientific knowledge. The old adage – never let the truth get in the way of a good story – is hard at work.

Jan 11th 2010
From Economist.com
Britain’s cold snap is explained by the Arctic oscillation

IT IS an ill wind that blows no good, as people have been remarking to each other since at least the 16th century. In the case of the bitter easterlies that have brought Britain colder, snowier weather than has been seen for a couple of decades, the proverbial benefit has been felt by the more foolish and facile of those who doubt the reality or likelihood of man-made climate change. “Snow Chaos: And still they claim it’s global warming” read the front page headline of Britain’s Daily Express on January 6th. The foolishness is not one sided. With less public prominence, those convinced of climatic doom mutter of “extreme events” being more likely in a more man-made climate, with the implication that this might in some way explain the current cold.

To try to make a climatic point either way out of a patch of unusual weather, though, is normally to be on a hiding to nothing, and so it is this winter. No one with any claim on the public’s respect has ever said that all of the natural ups and downs of climate will be ironed out onto a smooth upwards trend by greenhouse gases; their effects are expected to show up not so much in particular events, but in statistics. The reverse of the same coin is that there will still be cold snaps in a warming world. But that is not to say that the current cold might not have implications beyond the spring, or that it might not help explain more about how the climate actually works.

…

The two effects brought on by the extreme negative mode of the AO thus could cancel each other out. But it is also possible that one or other of them will win through, with a significant effect on this year’s summer ice. To some people, including, almost certainly, those who write the headlines in the Daily Express, the fact that the same phenomenon might explain either record low sea ice or continued recovery of sea ice will be seen as inconsistency, poor science, or something more suspect. To people actually interested in how the climate works, however, seeing what happens in a very strong negative AO may prove a boon, by allowing the roles of different processes in ice loss to be further disentangled. Weather and climate are not the same, but there are links between them in both directions—links which can usefully be understood.

One of the most valuable things about maintaining a blog is that I get critical comments that force me to defend my positions and think about contrary evidence.

I think you’re right, I was foolhardy to try to still the reasoning. However, I still think this chain captures many of the fallacies employed.

For those trying to do so, Greg Craven’s book and videos are a good resource.

This issue is too important to have a semi-formed opinion about, backed with whatever evidence you have happened across at random.

Very harrowing.

It happens all the time, and is a significant basic failing of most human reasoning.

What!

No!

Although, in some sense, it’s easy to see where this reasoning originates. Tell me if you think this is anything like what’s happening –

p1. Scientists claim 2009 is on track to be the warmest year on record, or one of the warmest (it was one of these) (true, I think)

p2. Toronto has its first snow-free november since 1847 (true, I heard on the radio)

c1. Toronto has its first snow-free november since 1847 because 2009 is one of the warmest years on record (fallaciously inferred from 1 and 2)

c2. The temperature in my city is directly related to global climate (fallaciously inferred from c1)

p3. Global warming means it gets warmer every year. (blatantly false)

p4. Interpretation: “gets warmer every year” means every day, month, season this year is warmer than last year (blatantly absurd interpretation)

p5. Today it is colder than the same day last year in Ottawa. (certainly true on numerous days every year regardless of overall city or global trend)

C3. Global warming is false or has stopped (from P3, P4, P5 and C2)