How to Deceive with Stats: the CBC’s guide to Canadian weather

According to the CBC  today “the area of Canada covered by snow at certain times of the year shrank by a third between 1972 and 2010.”

Another scare story devoid of context.  For most of the west, snowfall amounts depend on the La Niña/El Niño.  Here is a brief history of those events.  You can see that 1972 was a strong La Niña bringing above average snow.  2010 was a strong El Niño bringing less snow and a warm winter.  Have you figured out the trick in the article and why they chose to compare those two years?!

To create an inane headline, pick any el niño year with the lowest snow, from any large la niña snow year, and kapowie, instant alarm!  To the uninitiated reader, the choice of the two dates in the “study” is arbitrary leading them to imagine something is wrong.  To the student of weather history, the dates are specifically chosen  to create an imagined trend that does not actually exist. It is a dishonest and flagrant attempt to con the reader.  I’ve pretty much had enough of this.

For example, why not compare 1998 and 2011?  Because that would show “snow cover is increasing” to use their reasoning.  But that statement is just as misleading.   This fraudulent cherry picking isn’t all that’s misleading.

The infinitely complex mechanisms that cause snowfall in different regions of  Canada do not follow a linear trend.  Any trend calculated is a statistical artifact that has no meaning in the real world of cause and effect.  The record snowfall currently around the west further undermines their nonsense claims and shows why mechanism trumps trend.

Above is the automatic snow sensor up the highway from me with the current year in blue.  Does this bear any resemblance to the nonsense claim of declining snow cover?   See more stations here.

The article goes on to suggest that snow cover is a key variable for measuring climate change.  If that’s the case then what does the data indicate?

Here is the data from the Rutgers Snow Lab.  Globally, snow cover is in fact trivially increasing, but not beyond  the noise of the data.  From these numbers I can make all sorts of meaningless statements such as 3 of the last 5 years were the snowiest in 30 years which hardly fits the global warming hysteria presented by the CBC.  Or I can perform the same dishonest journalism practiced by the CBC and suggest that snow cover in the northern hemisphere has increased an average of 160,000 square km per year between 1981 and 2012!  Run for the hills, the ice age is upon us!  Or not.

Things like trend lines will often confuse as it implies a mechanism.  Back to the present story, Canada is so utterly massive that the whole concept treating 10 million square kilometers as one thing is nonsense to begin with.  The mechanisms that ebb and flow to make it snow in Abbotsford have nothing in common with what makes it snow in Baffin Island or Nipigon.  The peaks and valleys of the weather in these distant regions can be measured, added to together, and averaged- but this number is no longer a physical thing.  It has divorced itself of any physical phenomena that produce it.  If we averaged Goose Bay snow cover and Manchester England snow cover, no one would take it seriously.  Yet Manchester is closer than much of BC.

I can sum up CBC’s logic thusly:

If it was sunny yesterday and raining today, on average, it’s getting drier!

As always, the worst part of CBC’s apparent campaign to convince me the world is ending(??!!!) is that I pay for it.  At least I’m soon to be paying a little less for it!

screencap from CBC’s “science” page:

 

 

 

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One Response to How to Deceive with Stats: the CBC’s guide to Canadian weather

  1. Awesome analysis.

    Have you ever tried to reach one of the people that submits these stories and ask them what the hell they are thinking? Is this the only way they can get paid?

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